CHARLES S. TURNER,CHRISTOPHER D. TURNER,RUSSELL L. OVERTON, LEVY ROUSE, CLIFTON E. YARBOROUGH, KELVIN D. SMITH, & TIMOTHY CATLETT , 116 A.3d 894 ( 2015 )


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    DISTRICT OF COLUMBIA COURT OF APPEALS
    Nos. 12-CO-1362, 12-CO-1538, 12-CO-1539,
    12-CO-1540, 12-CO-1541, 12-CO-1542, & 12-CO-1543
    CHARLES S. TURNER,
    CHRISTOPHER D. TURNER,
    RUSSELL L. OVERTON,
    LEVY ROUSE,
    CLIFTON E. YARBOROUGH,
    KELVIN D. SMITH,
    &
    TIMOTHY CATLETT,
    APPELLANTS,
    V.
    UNITED STATES,
    APPELLEE.
    Appeals from the Superior Court
    of the District of Columbia
    (FEL-8615-84, FEL-8513-84, FEL-8612-84, FEL-8613-84,
    FEL-8614-84, FEL-8616-84, & FEL-8617-84)
    (Hon. Frederick H. Weisberg, Motions Judge)
    (Argued April 29, 2014                                  Decided June 11, 2015)
    John S. Williams, with whom Robert M. Cary, Cadence Mertz, Jennifer M.
    Sasso, and Frances Y. Walters were on the brief, for appellant Clifton Yarborough.
    2
    Kevin D. Feder, with whom Michael E. Antalics, Joana Nairn, and Meredith
    Garagiola were on the brief, for appellant Russell L. Overton.
    Jennifer Wicks was on the brief for appellant Charles Turner.
    Shawn Armbrust, Barry J. Pollack, Michael B. Bernstein, and Justin P.
    Hedge were on the brief for appellant Christopher Turner.
    Veronice A. Holt was on the brief for appellant Levy Rouse.
    Donald P. Salzman was on the brief for appellant Kelvin D. Smith.
    Cory Lee Carlyle was on the brief for appellant Timothy Catlett.
    Nicholas P. Coleman, Assistant United States Attorney, with whom Ronald
    C. Machen Jr., United States Attorney at the time the brief was filed, and Elizabeth
    Trosman, Suzanne Grealy Curt, James Sweeney, Kacie Weston, and Colleen
    Kennedy, Assistant United States Attorneys, were on the brief for appellee.
    Robert B. Humphreys and Steven Schulman filed a brief on behalf of The
    Innocence Network as amicus curiae in support of appellants.
    Stephen P. Braga filed a brief on behalf of The National Association of
    Criminal Defense Lawyers as amicus curiae in support of appellants.
    John C. O’Quinn, Savaria B. Harris, Traci M. Braun, Deborah S. Decker,
    and Michael B. Potere filed a brief on behalf of False Confessor Exonerees as
    amicus curiae in support of appellants.
    Julia M. Jordan, Lee Ann Anderson McCall, and Elizabeth A. Cassady filed
    a brief on behalf of Former Judges and Prosecutors as amicus curiae in support of
    appellants.
    Aderson Bellegarde François filed a brief on behalf of Howard University
    School of Law Criminal Justice Clinic & Civil Rights Clinic as amicus curiae in
    support of appellants.
    Douglas Baruch, Jessica P. Neiterman, and Sujata Jhaveri filed a brief on
    behalf of Former Law Enforcement Officers as amicus curiae in support of
    appellants.
    3
    Before GLICKMAN and BLACKBURNE-RIGSBY, Associate Judges, and
    NEBEKER, Senior Judge.
    GLICKMAN, Associate Judge: In 1985, appellants were tried and convicted
    for the kidnapping, armed robbery, and first-degree felony murder while armed of
    Catherine Fuller on October 1, 1984. This court affirmed their convictions on
    direct appeal. Some twenty-five years later, appellants returned to Superior Court
    with motions to vacate their convictions pursuant to D.C. Code § 23-110 (2012
    Repl.) and the Innocence Protection Act (“IPA”), D.C. Code § 22-4135 (2012
    Repl.).    Appellants claimed that they did not receive a fair trial because the
    government withheld exculpatory and impeachment evidence in violation of its
    obligations under Brady v. Maryland,1 and that newly discovered evidence,
    including witness recantations, established their actual innocence of the crimes
    against Mrs. Fuller.    Appellant Yarborough additionally claimed that his trial
    counsel was constitutionally ineffective in failing to investigate his intellectual
    disabilities as grounds for suppressing the videotaped statement he made when he
    was arrested, which the government used against him at trial.
    1
    
    373 U.S. 83
    (1963).
    4
    Appellants’ motions were assigned to the Honorable Frederick H. Weisberg.
    He presided over a three-week evidentiary hearing on their claims in mid-2012.
    Judge Weisberg thereafter denied the motions in a written order. Before us now
    are the appeals from that decision.
    We affirm. As we shall explain, we conclude that appellants’ Brady claims
    fail because appellants have not shown a reasonable probability that the outcome
    of their trial would have been different had the government disclosed the withheld
    evidence in timely fashion. Appellants’ IPA claims fail because the motions judge
    found the witness recantations to be incredible and appellants therefore have not
    established their actual innocence by a preponderance of the evidence. Finally, we
    reject Yarborough’s ineffective assistance claim because he has not shown that he
    was prejudiced by his trial counsel’s allegedly deficient performance.
    Table of Contents
    I. The Murder of Catherine Fuller and Appellants’ 1985 Trial……………. 5
    A. The Government’s Case at Trial……………………………………… 6
    B. The Defendants’ Alibis and the Government’s Rebuttal ……………..11
    C. Verdicts and Direct Appeal ……..……………………………………13
    II. Appellants’ Post-Conviction Motions: Brady and IPA Claims ………...15
    A. Witness Recantation………………………………………………… 15
    1. Calvin Alston and Harry Bennett …………………………………15
    1. Melvin Montgomery and Linda Jacob …..……………………….19
    B. Evidence Not Disclosed to the Defense……………………………..20
    1. Undisclosed Alternative-Perpetrator Evidence ……………….….20
    5
    a. The Witness in the Alley………………………………………. 20
    b. James McMillan……………………………………………….. 21
    c. James Blue…………………………………………………….. 24
    2. Impeachment Evidence ……………………………...……………28
    C. Expert Testimony………………………………………………........ 30
    D. The Motions Judge’s Decision…………………………………… …31
    III. Analysis of Appellants’ Brady Claims………………………………… 34
    A. Brady and the Applicable Standard of Review ……………….…......34
    B. The Witnesses in the Alley …………………………………………...40
    C. James McMillan Evidence …………………..………………………41
    1. The October 1984 Robberies ……………………………………...42
    2. The 1992 Murder of A.M. …………….………………………….46
    D. Ammie Davis’s Accusation of James Blue ………………………….47
    E. Impeachment Evidence ……………………………………………...56
    F. Cumulative Materiality of the Undisclosed Evidence ………………60
    IV. Analysis of Appellants’ IPA Claims …………………………………...68
    V. Yarborough’s Claim of Ineffective Assistance of Counsel …………….76
    A. Background ………………………………………………………….77
    1. Yarborough’s Statement to Police ……………………………….77
    2. Yarborough’s Suppression Motion …..……………………….….78
    3. The Hearing on Yarborough’s Ineffective Assistance Claim ……80
    B. Analysis ………………………………..……………………………86
    VI. Conclusion …………………………………………………………….94
    I. The Murder of Catherine Fuller and Appellants’ 1985 Trial
    Shortly after 4:30 p.m. on October 1, 1984, Catherine Fuller left her home
    on foot to go shopping. Around 6:00 p.m., William Freeman, a street vendor,
    discovered her lifeless body lying in a garage in the middle of an alley between 8th
    and 9th Streets Northeast, just north of H Street. One of the garage doors was
    open, enabling Freeman to catch sight of Fuller’s body when he entered the alley to
    relieve himself. Mrs. Fuller had been badly beaten and violently sodomized, and
    6
    had suffered massive blunt force injuries, including a ruptured liver and broken
    ribs. Her clothing and property were found strewn about the garage and the alley.
    The police were unable to find the object used to commit the sodomy or to recover
    any usable fingerprints or other physical evidence that could identify the
    perpetrators. The medical examiner could not determine from Fuller’s injuries
    how many persons were involved in assaulting her.
    After conducting more than 400 interviews, investigators developed the
    theory that Fuller was assaulted and killed by a large group of teenagers who
    initially set out, on the spur of the moment, to rob her. A total of thirteen
    individuals believed to have been members of that group were indicted. Two of
    them, Harry Bennett and Calvin Alston, pleaded guilty and agreed to testify for the
    government. A third defendant, James Campbell, whose case was severed for trial
    after his attorney became ill, eventually pleaded guilty as well. The remaining
    defendants—the seven appellants before us now and their co-defendants Steven
    Webb, Alphonzo Harris, and Felicia Ruffin—went to trial in the fall of 1985.
    A. The Government’s Case at Trial
    At the center of the government’s case was the testimony of the two
    cooperating witnesses, Bennett and Alston.       Bennett had pleaded guilty to
    7
    manslaughter and robbery, Alston to second-degree murder.          They provided
    similar accounts of the events leading to Fuller’s death. According to them both,
    they were in a group of young men, including appellants, who were gathered in a
    park at 8th and H Streets Northeast on the afternoon of October 1, 1984, when they
    observed Fuller across the street.    Alston admitted being the one who, after
    appellant Catlett sang a song about needing money, suggested that the group rob
    Fuller. Members of the group split into two bodies and crossed the street to attack
    Fuller at the alley between 8th and 9th Streets. Bennett, Alston, and others,
    including appellants, punched and kicked her, hit her with a stick or board,
    knocked her to the ground, and robbed her of her money and jewelry. Fuller then
    was dragged into a garage and stripped nearly naked. As some in the group held
    her legs and others stood and watched, appellant Rouse took a pole or pipe-like
    object and shoved it into her rectum. The group then dispersed.
    Although Bennett and Alston agreed on the preceding outline of events, they
    differed on some important matters. Notably, while Bennett testified that appellant
    Yarborough did not accompany the group into the alley, Alston recalled that
    Yarborough actively participated in kicking Fuller as she lay on the ground there.
    And while Bennett remembered that Alston and Webb held Fuller’s legs as Rouse
    sodomized her, Alston thought appellants Overton and Charles Turner did so. In
    8
    addition, Bennett and Alston each had made prior inconsistent statements to the
    police and the grand jury regarding who was present in the park and who
    participated in attacking Fuller.
    Four witnesses to the crime corroborated Bennett and Alston’s account.
    Two of them, Carrie Eleby and Linda Jacobs, testified that they came upon the
    attack when it was already in progress.      Eleby implicated appellants Catlett,
    Overton, Christopher Turner, Smith, and Rouse, as well as Alston and Webb. She
    also put appellant Yarborough in the alley, but she did not remember seeing him
    attack Fuller.   Jacobs saw Christopher Turner and Smith in the alley.         Both
    witnesses saw Rouse sodomize Fuller.
    Eleby and Jacobs had significant credibility problems.       Both were PCP
    users. Eleby contradicted herself, could not keep names and dates straight, and
    claimed she did not remember anything she had told the police or the grand jury.
    Jacobs, too, was a difficult witness who contradicted herself on the stand and had
    trouble answering questions. Moreover, each witness’s account was impeached or
    contradicted by other testimony. For example, contrary to her testimony at trial,
    Eleby told police that she and Jacobs arrived at the alley only after the police and
    the morgue staff were there, and she told the grand jury that appellant Smith did
    9
    not hit or kick Fuller. In addition, Eleby testified that she and Jacobs were with
    their friend Tawana when they heard a scream coming from the alley, turned
    around and saw a group attacking a woman. But Jacobs testified they were not
    with Tawana and did not hear a scream. She claimed they were prompted to enter
    the alley by their friend Annette Taylor. But Taylor denied this and testified that
    she was nowhere near the scene at the time.
    The other two eyewitnesses were Melvin Montgomery and Maurice
    Thomas. Montgomery testified that he saw appellants Catlett, Charles Turner,
    Overton, and Rouse standing with others in the park. Montgomery heard Catlett
    singing a Chuck Brown song about needing money, saw Overton point across the
    street at Fuller, and watched as those four appellants and others crossed the street
    in her direction.2
    Fourteen-year-old Maurice Thomas testified that he passed the alley and saw
    a group of people surrounding a woman. Those he saw included appellants Catlett,
    Yarborough, Rouse, Charles Turner, and Christopher Turner, and may have
    2
    Montgomery, who knew each of the appellants, also saw Yarborough in
    the park, but not until after the assault on Fuller was over.
    10
    included appellant Smith and Harry Bennett.3 Thomas saw Catlett pat down the
    woman and then place something in his pocket. Catlett then hit her and when she
    fell to the ground, the rest of the group assaulted her. Later that evening, Thomas
    heard Catlett tell someone that “we had to kill her because she spotted someone”
    Catlett was with.
    The government put on other important evidence of appellants’ guilt in its
    case-in-chief. First, the jury was shown a redacted videotape of Yarborough’s
    statement to the police, in which he placed himself in the park, the alley, and the
    garage before and during the attack on Fuller. (The statement was admitted only
    against Yarborough.)
    Second, Kaye Porter testified that she had asked Catlett about the rumors she
    had heard concerning the Fuller murder. Catlett responded that “all he did was
    kick her and somebody else stuck the pole up in her” because “she wasn’t acting
    right.”4 Finally, Detective Daniel Villars testified that he overheard Christopher
    Turner tell Overton that the police lacked sufficient evidence against them because
    3
    Thomas did not see Overton in the alley.
    4
    Porter was impeached with her grand jury testimony in which she said
    Catlett denied any involvement in the crime.
    11
    they had not touched Fuller’s body and so did not leave any fingerprints. Overton
    agreed that the police lacked evidence and commented that he knew the two people
    who gave them up. Turner replied that he knew one of the two, but that he
    wondered how the police knew he, Overton, and “everybody” were in the alley.
    B. The Defendants’ Alibis and the Government’s Rebuttal
    Appellants Overton, Smith, Christopher Turner, Charles Turner, and Rouse
    put on alibi defenses.5 Overton’s alibi was supported by three witnesses. Marita
    Michaels testified that she was in the park at 8th and H Streets with Overton and
    others from about 10:00 a.m. to about 2:30 p.m. on October 1, drinking and
    smoking marijuana. Michaels said that she and Overton left the park together and
    that she saw him walking towards his house, appearing very drunk. Overton’s
    grandmother Edna Adams, and his sister Lottie Overton, testified that he left the
    house that morning, and returned home drunk between 2:00 and 3:00 p.m. Adams
    said he remained home and slept until 7:30 p.m.; Overton’s sister confirmed that he
    remained at home on October 1 until at least 5:00 p.m., when she left the house
    5
    Appellant Yarborough’s attorney proffered in his opening statement that
    the evidence would show Yarborough was at his girlfriend’s house at the time of
    Fuller’s murder, but no such evidence was presented. (Yarborough’s girlfriend,
    Chandera Hill, did testify, but only to the fact that Maurice Thomas disliked
    Yarborough.)
    12
    herself. Overton’s family members admitted, however, that his grandmother’s
    memory was weak and that his sister and mother had reminded her of many of the
    details in her testimony. Adams was impeached on various details with her grand
    jury testimony. Lottie Overton was impeached with her grand jury testimony that
    Overton had asked her to ask people he knew in the park to be witnesses for him,
    which was contrary to her trial testimony that he did not do so. Even after being
    presented with the transcript, she denied having said this to the grand jury. But
    Adams testified that Overton did tell Lottie and his mother to go ask certain people
    to be witnesses. Overton himself did not testify at trial.
    Smith and Christopher Turner testified that they were at Smith’s house on
    October 1. They said they first learned of Fuller’s death later that night in a phone
    call from a girl named Renee Walker. Three of Smith’s relatives corroborated his
    and Christopher Turner’s alibis. Before the grand jury, however, they testified that
    Smith knew about Fuller’s murder as early as 6:00 p.m. on October 1.
    Rouse and Charles Turner had conflicting alibis. Rouse testified that he
    spent the afternoon of October 1 at a recreation center, restaurants and arcades with
    Charles Turner and a friend named Christopher Taylor, that he went to the alley at
    8th and H Streets only after the police were already there, and that he then went at
    13
    around 7:00 p.m. to the home of his girlfriend Catrina Ward. But Charles Turner
    testified he was at home at the time of Fuller’s murder and left there only when
    Rouse and a friend named Vincent Gardner came by and told him someone had
    been killed in the alley behind H Street.
    Christopher Taylor corroborated Rouse, but he was impeached with his
    admissions to police that he was in the park and heard the group decide to assault
    Fuller, and that he was in the alley and saw the murder. Catrina Ward confirmed
    that Rouse came to her house on the night of October 1. She also testified,
    however, that she saw blood splattered on the bottom of Rouse’s pants leg, and that
    on later occasions Rouse told her he saw Fuller get killed and boasted that he “did
    the worst thing to that lady in the alley.” Charles Turner was impeached with his
    statement to the police that Rouse and Gardner did not tell him about the crime.
    And Gardner, testifying as a rebuttal witness, denied going to Charles Turner’s
    house or going anywhere with Rouse on the night of October 1.
    C. Verdicts and Direct Appeal
    The case was submitted to the jury on December 9, 1985. On the morning
    of December 16, the jury asked to see the videotape of Yarborough’s incriminating
    statement to the police. That afternoon, after seven days of deliberations, the jury
    14
    returned guilty verdicts against Catlett, Rouse, Smith, Charles Turner, Yarborough,
    and Webb; at the same time, the jury found their co-defendants Harris and Ruffin
    not guilty. The jury deliberated for an additional two days before returning its
    verdicts of guilty against the remaining defendants, appellants Overton and
    Christopher Turner.
    This court affirmed the convictions on direct appeal.6 In doing so, we
    acknowledged “some conflict in the testimony of the government’s witnesses
    regarding exactly when each appellant joined in the beating,” but stated that “there
    was overwhelming evidence that each of them was involved at one time or
    another.”7 For the most part, appellants’ claims on direct appeal do not bear
    directly on the claims now before us.8
    6
    See Catlett v. United States, 
    545 A.2d 1202
    (D.C. 1988); Turner v. United
    States, Nos. 86-314 & 90-530 (D.C. 1992) (Mem. Op. & J.).
    7
    
    Catlett, 545 A.2d at 1206
    n.2; see also 
    id. at 1209-10,
    1217 (discussing the
    evidence against Christopher Turner and Overton, respectively).
    8
    The exception is Yarborough’s argument on direct appeal that the trial
    court erred in denying his motion to suppress his videotaped statement without
    considering his age, education, and experience with the criminal justice system.
    
    Id. at 1207.
    We discuss this below in connection with Yarborough’s ineffective
    assistance claim.
    15
    II. Appellants’ Post-Conviction Motions:
    Brady and IPA Claims
    In support of their Brady and IPA claims, appellants presented witness
    recantations, expert witness testimony, and other evidence at the hearing on their
    post-conviction motions in 2012 in an effort to show that the government withheld
    materially exculpatory and impeachment evidence from them at trial, and that they
    were actually innocent of Fuller’s robbery, kidnapping, and murder. Appellant
    Yarborough also testified and presented evidence in support of his ineffective
    assistance claim. In opposition, the government presented testimony from the
    investigating detectives and the prosecutors who worked the case in 1984 and
    1985. This section of our opinion discusses the evidence relevant to appellants’
    Brady and innocence claims; we discuss the evidence particularly relevant to
    Yarborough’s ineffective assistance claim in a later section.
    A. Witness Recantations
    1. Calvin Alston and Harry Bennett
    Alston and Bennett had finished serving their sentences when they took the
    stand in 2012 to recant their trial testimony. Each maintained that he knew nothing
    about Fuller’s murder but had been pressured by police into making a false
    confession and, ultimately, testifying falsely at trial.
    16
    Alston was arrested and questioned by Detectives McGinnis and Sanchez
    about the murder for two-and-a-half hours on November 29, 1984. According to
    Alston, the detectives yelled at him, accused him of lying, and threatened him with
    a life sentence if he did not admit his complicity in the murder. They accused him
    of acting as a lookout for Rouse, Yarborough, Overton, Smith, and others they
    named. Eventually, Alston testified, he “gave in to their drilling” and falsely
    admitted to being the lookout and witnessing the attack on Fuller from the end of
    the alley.
    This, Alston said, did not satisfy his interrogators.      Detective Sanchez
    angrily told Alston he could not have seen or heard what was going on in the alley
    if he merely stood at the end of it. The detectives insisted that he had witnessed
    Fuller being beaten and sodomized in the garage and urged him to “come all the
    way clean” and put himself “in the case.”          Ultimately, Alston testified, he
    acquiesced and concocted a story of having participated in the crime using the
    information the detectives provided concerning what happened and who did it.
    (Nevertheless, Alston still did not admit to personally assaulting Fuller or being the
    one who proposed robbing her, and he steadfastly denied having received any
    money from the robbery.) After rehearsing his story with the detectives, they
    turned on the video camera and recorded his statement.
    17
    Bennett, who was interrogated for about four hours after he was arrested on
    February 6, 1985, similarly claimed that the detectives refused to believe his
    denials, threatened him with a life sentence, and “kept hammering” at him until he
    eventually “started saying what was on the news” and repeating whatever the
    detectives said to him “until they got me to say I was involved.” The detectives
    pressed him to incriminate others, including several of the appellants here, and he
    did so. Bennett’s interrogation also culminated in a videotaped statement. During
    the videotaping, Bennett testified, the detectives turned the camera off to correct
    details in his story. At one point, Bennett claimed, he told them that everything he
    had said was a lie, and the detectives became angry, rewound the tape, and
    recorded over that portion. Later on, Bennett testified, he was shown part of
    Yarborough’s videotaped statement and given documents pertaining to the case so
    that he could further tailor his testimony.
    Alston and Bennett also claimed that the lead prosecutor in the Fuller case,
    Jerry Goren, instructed them to alter their testimony at trial. Alston asserted that
    Goren told him he needed “to put my actual self in the violence that took place” to
    make his testimony more credible, and to “change the scenario” when other
    evidence conflicted with his account of the attack on Fuller.       Alston said he
    complied with Goren’s demands when, for example, he testified at trial that he
    18
    himself came up with the idea to rob Fuller.9             Bennett made comparable
    allegations. For example, in his videotaped statement, Bennett said he did not see
    Christopher Turner enter the alley or Catlett hit Fuller; at trial, he testified both of
    them participated in the beating. He changed his story, he claimed, “because that’s
    what they told me to say.”10
    To rebut Alston’s and Bennett’s recantations and repudiate their allegations
    of misconduct, the government called Jerry Goren and Detectives McGinnis and
    Sanchez, among other witnesses. The detectives denied threatening Alston and
    Bennett with life sentences or telling them what to say or whom to name as
    9
    Similarly, Alston retreated at trial from his previous statement that he saw
    Rouse hit Fuller in the back of the head with a two-by-four, and testified instead
    that he did not see where Rouse hit her, because Goren told him there was no
    evidence that Fuller was injured in the back of the head.
    10
    To support the credibility of Alston’s and Bennett’s recantations,
    appellants presented other witnesses who testified to the detectives’ heavy-handed
    interrogation tactics. In addition, over the government’s objection, appellants
    called an expert on the subject of false confessions. The witness, Dr. Richard Leo,
    opined that certain features of the interrogations of Alston and Bennett, such as the
    detectives’ use of deception, yelling, and threats or promises, were associated with
    a heightened risk of inducing false confessions. According to Dr. Leo, the errors
    and incongruities in the confessions of Alston and Bennett could be taken as
    “indicia of unreliability.”
    19
    Fuller’s assailants.11 They similarly denied Alston’s claim that they rehearsed with
    him what he would say on camera and Bennett’s claims that they interrupted the
    taping of his statement to excise his declaration that his confession was a lie, and
    that they showed him Yarborough’s taped statement and documents containing
    information about the investigation. Goren likewise categorically denied telling
    Alston and Bennett what to say, or that they needed to change their testimony.
    2. Melvin Montgomery and Linda Jacobs
    Appellants also called Melvin Montgomery and Linda Jacobs to testify at the
    2012 hearing. Their testimony proved to be unhelpful to appellants. Montgomery
    signed an affidavit in 2009 stating he lied on the stand in 1985 and that he saw
    appellants in the park at 8th and H Streets on October 1 only in the morning, not in
    the late afternoon (when Fuller was murdered). At the 2012 hearing, however,
    Montgomery disavowed the affidavit and denied perjuring himself at trial.
    Linda Jacobs professed not to remember her trial testimony or much of
    anything else, but she insisted that she knew everything she said at trial was a lie
    11
    The detectives admitted, however, to playing good-cop-bad-cop, yelling,
    pointing, and slamming their hands on desks. They also acknowledged telling
    Alston and Bennett they would face greater consequences if they did not come
    clean and finger others.
    20
    because she was never in the alley on October 1. She vaguely claimed the police
    told her she was in the alley and “fed [her] information” about the murder, which
    she repeated to avoid being returned to her parents or accused of the crime herself.
    When the judge asked her what the government told her to say in 1985, she broke
    down emotionally and struggled to articulate how Fuller’s murder made her feel.
    B. Evidence Not Disclosed to the Defense
    Appellants contended that the government withheld evidence that the
    defense could have used (1) to construct an alternative-perpetrator defense
    premised on the theory that Fuller was attacked and killed by a single individual
    (or at most a very small number of persons); and (2) to impeach the prosecution
    witnesses who identified appellants as the perpetrators.
    1. Undisclosed Alternative-Perpetrator Evidence
    a. The Witnesses in the Alley
    According to information contained in the files of the police and the
    prosecutors, three people—Jackie Watts, Willie Luchie, and Ronald Murphy—told
    investigators that at around 5:30 p.m. on October 1, they happened to be walking
    through the alley and by the garage where Fuller was murdered. Luchie and Watts
    21
    heard the sound of groans coming from inside the garage. (Murphy recalled Watts
    saying she heard something like a groan, though he did not claim to have heard
    anything himself.) According to Luchie, both doors of the garage were closed at
    this time. The trio continued on their way without investigating the source of the
    groans. This information was not disclosed to the defense. At the 2012 hearing,
    Goren agreed that if the witnesses heard groaning at 5:30 p.m., it meant Fuller was
    still alive at that time. He also agreed that if (counterfactually, in his view) the
    assault was still in progress at that time, it could not have involved more than one
    or a very few assailants.
    b. James McMillan
    James McMillan is one of two persons appellants claim they could have
    argued at trial was the likely alternative, sole perpetrator of Fuller’s murder had the
    government not withheld information about him.
    At trial in 1985, William Freeman, the street vendor who discovered
    Fuller’s body, testified that as he waited for the police to come, he saw two men
    run into the alley from 9th Street and stand very close to the garage for a few
    minutes. Freeman earlier had seen the two men walking up and down 8th Street.
    22
    One of the men appeared to be concealing an object under his coat. When the
    police arrived, the two men ran away up the alley towards I Street.
    What Freeman saw was, of course, known to the defense. What the defense
    did not know, and the government did not disclose, was who the two men were.
    Freeman had identified them to the police as James McMillan and Gerald
    Merkerson. It was McMillan who appeared to be hiding something under his coat.
    McMillan was a potential suspect in the police investigation. Two other
    witnesses told police they saw him at the alley at the same time Freeman did, and
    they confirmed Freeman’s observations of his suspicious behavior. (These
    witnesses also were not disclosed to the defense.) In addition, the police knew that
    McMillan lived on 8th Street about three doors down from the alley and that he
    had violently assaulted and robbed two other middle-aged women walking in the
    vicinity three weeks after Fuller’s death.12    But although the police included
    McMillan’s photograph in the album they showed witnesses to try to identify the
    12
    McMillan committed the first of these robberies on October 24, 1984, in
    an alley behind the 1100 block of K Street Northeast. He approached the victim
    from behind, knocked her to the ground, grabbed her purse and fled. The next day,
    McMillan and a companion assaulted a woman in the 600 block of 12th Street
    Northeast. One of the two struck her in the face, breaking her nose, and stole the
    bag she was carrying.
    23
    persons responsible for Fuller’s murder, the government did not obtain sufficient
    evidence to indict him.13
    At the motions hearing in 2012, appellants presented information about
    McMillan’s subsequent activities following his conviction of the two robberies that
    he committed in October 1984. McMillan was sentenced to serve eight to twenty-
    five years in prison. Two months after he was released from prison in July 1992,
    he killed a 22-year-old woman (“A.M.”) in an alley behind the 500 block of 8th
    Street Northeast, only a few blocks from where Fuller was murdered. This crime
    had some striking similarities to the attack on Fuller: McMillan abducted A.M. as
    she walked down the street and dragged her to a secluded spot in the alley,
    ransacking her personal belongings and leaving them strewn along the path of
    abduction. After forcing A.M. into a narrow space behind a parked car, McMillan
    stripped off her underwear, beat her ferociously, and sodomized her.         A.M.
    13
    With two exceptions, no one directly implicated McMillan in the murder.
    The exceptions were as follows. First, as appellants were aware, James Campbell
    (the co-defendant whose case was severed) gave a videotaped statement to the
    police, and in it he named McMillan as one of several individuals congregating in
    the park at 8th and H Streets who participated in the attack on Fuller. Second,
    when Christopher Taylor (whom Rouse called at trial to support his alibi) was
    interviewed by police, he identified McMillan from his photograph as having been
    part of the group that accompanied Rouse into the alley. Campbell and Taylor
    subsequently disavowed their statements, and the government realistically could
    not have used them to prosecute McMillan.
    24
    suffered grievous injuries and died three days later. McMillan was convicted of
    her murder and remains incarcerated.
    Appellants argued that this was powerful evidence supporting the thesis that
    it was McMillan who murdered Fuller. In support of that thesis, they presented Dr.
    Richard Callery, a forensic pathologist, who testified that the cause of death for
    both Fuller and A.M. was blunt force trauma to the head and torso, and that each
    victim had suffered a traumatic anal sodomization resulting in severe internal
    injuries. Dr. Callery could not say the two murders were “signature crimes,” but
    he testified that, in his experience, anal sodomy with an object occurred in
    considerably less than one percent of homicide cases. In addition to Dr. Callery’s
    testimony, appellants presented a stipulation that, if he were called, an expert in
    sexual dysfunctions would testify that someone who commits an act of violent anal
    sodomy is likely to commit the act more than once.
    c. James Blue
    Other information not disclosed to the defense concerned an accusation
    against a man named James Blue, a habitual criminal who, by 1984, had served
    time for assault and had a record of arrests for rape, sodomy, and armed robbery.
    On October 26, 1984, a police lieutenant named Frank Loney happened to be
    25
    interviewing a woman named Ammie Davis, who was alleging police misconduct
    in connection with her arrest for disorderly conduct. According to Loney’s written
    report of the interview, Davis inquired what would happen if she gave the officer
    “something on a homicide.” Insisting that she did not want to get involved and
    would not testify in court, Davis proceeded to state that someone who just got out
    of jail on October 1 killed a woman that same day “for just a few dollars” in an
    alley off of H Street. At first Davis said she was present when the man committed
    the murder; she then said she was not “with” him and only saw him grab the
    woman by the back of the neck and pull her into the alley. 14 Davis said she was
    with her girlfriend “shooting stuff” when this happened and that her girlfriend saw
    it too.    Davis refused to divulge her girlfriend’s name but said she and her
    girlfriend would call the lieutenant the following week.      At this point in the
    conversation, Lieutenant Loney asked Davis to tell him the man’s name. After
    hesitating and saying she did not want to talk about it, Davis responded that “James
    Blue did it.”
    Davis was reluctant to say anything more. She refused to give a written or
    recorded statement and declared that she would not “go to court.” Acknowledging
    14
    When asked whether the man used a weapon, Davis said “he beat the f**k
    out of her.”
    26
    that she was afraid of Blue, she brought the interview to a close with the assurance
    that she would call Lieutenant Loney and let him talk to her girlfriend. Davis
    never did call back, however.
    Lieutenant Loney filed his report of Davis’s statement without bringing it
    directly to the attention of the detectives who were investigating Fuller’s murder.
    It did not come to their attention until August 1985.15 Goren then proceeded to
    interview Davis on August 8 and 9. At the hearing in 2012, he recalled her as
    being “not serious” and “very playful” in their meeting and having nothing to add
    to what she previously had said about Blue.
    Goren testified that he ultimately decided not to inform the defendants in the
    Fuller case of Davis’s allegation because he “believed completely and strongly that
    Ms. Davis had no evidence in this case and that she was totally incredible.” Goren
    came to that conclusion because Davis had given Loney two different versions of
    her story; she was unable to provide any further details or any information that
    could be corroborated; the only information she could provide about the girlfriend
    who purportedly would have confirmed her account was that her nickname was
    15
    Detective McGinnis recalled asking Loney why he had not alerted them.
    Loney told him he did not believe what Davis had said.
    27
    “Shorty”; Davis previously had accused Blue of another, unrelated murder and
    provided information that was determined to be false16; and the prosecutors were
    confident in their body of evidence pointing elsewhere, i.e., at appellants and the
    other charged defendants. No other evidence implicated Blue in Fuller’s murder.
    Goren admitted, though, that Davis accurately stated that Blue was released from
    prison on October 1, and that she evidently knew where Fuller was murdered and
    that she was not attacked with a knife or a gun.
    On October 9, 1985, prior to the start of appellants’ trial, James Blue shot
    and killed Ammie Davis. He was convicted of her murder and died in prison in
    1993.17
    16
    Goren learned about Davis’s prior accusation of Blue in another homicide
    investigation from an Assistant United States Attorney who had conducted that
    investigation and who was assisting Goren with the Fuller case.
    17
    Goren testified that he reviewed the homicide file relating to Davis’s
    murder and determined that it was unrelated to her accusation of Blue in the Fuller
    case.
    28
    2. Impeachment Evidence
    The government failed to turn over four types of impeachment evidence.18
    First, the government inadvertently did not disclose that Kaye Porter lied to the
    police at Carrie Eleby’s behest. During one of Eleby’s early interviews with the
    police in November, in which she denied having witnessed Fuller’s murder, she
    claimed that Alston had confessed his involvement in the crime to her. Porter, who
    accompanied Eleby to the interview, corroborated this claim. Porter later admitted
    to the police that she did not witness the conversation between Eleby and Alston,
    and that she had lied about it at Eleby’s request. Neither Porter’s lie nor Eleby’s
    suborning of it were disclosed to the defense.
    Second, the government did not disclose its knowledge of Eleby’s extensive
    PCP use. At trial, she testified that she smoked PCP on October 1, but never
    before or since. Goren and other members of the investigation and prosecution
    team knew this was not the truth. Eleby was actually under the influence of PCP
    18
    Appellants (somewhat vaguely) charge that the government failed to turn
    over a fifth category of impeachment evidence, to the effect that Carrie Eleby and
    Linda Jacobs initially denied witnessing the attack on Fuller and stood by their
    denials for months. But Goren testified that he gave the defense Eleby’s grand jury
    testimony in which she acknowledged her denials, and the trial record suggests that
    the defense knew of Jacobs’s denials, because she was asked about it on cross-
    examination.
    29
    even when she viewed photos and identified persons who were in the alley, and
    Goren’s notes indicate that she “had started using PCP again” later in the
    investigation.
    Third, the government did not disclose grand jury testimony supporting the
    alibi of a man named Lamont Bobbit, who Alston testified was present in the park
    and in the alley when Fuller was murdered.          Bobbitt told the police he was
    elsewhere that evening, and in testimony before the grand jury, six witnesses
    corroborated his alibi.   (The prosecutors did not believe the alibi because of
    contradictions in the testimony, but they decided they nonetheless lacked sufficient
    evidence to charge Bobbitt with Fuller’s murder.)
    Finally, the government did not disclose evidence that could have been used
    to impeach Maurice Thomas. At trial, Thomas testified that after he witnessed the
    attack in the alley, he ran home and told his aunt “Barbara” what he had seen. He
    claimed that Barbara told him not to say anything to anyone else. The police
    interviewed Barbara (whose real name was Dorothy Harris), and she said that she
    did not recall Thomas ever telling her anything about the attack.
    30
    C. Expert Testimony
    Two expert witnesses testified in 2012 in support of the theory that Fuller
    probably was killed by one to three attackers rather than a large group, though they
    both admitted it was possible a larger group was involved. Dr. Callery (who also
    testified to the similarities between the murders of Fuller and A.M.) examined the
    autopsy report and opined that Fuller’s injuries were not as extensive or widely
    distributed as he would have expected to see from a large-group attack, even if
    some members of the group merely held the victim and did not inflict injury
    themselves.   Dr. Callery agreed, however, with the 1985 medical examiner’s
    conclusion that it was impossible, from looking at the autopsy report, to say
    specifically how many people assaulted Fuller.
    The second witness was Larry McCann, an experienced homicide
    investigator who testified as an expert in violent crime analysis and crime scene
    reconstruction. It was McCann’s opinion, based on the autopsy report, crime scene
    photos and other investigation records, that the attack on Fuller was more likely
    committed by a single offender than by a large group of individuals acting
    together. Had there been multiple offenders, McCann testified, he would have
    expected to see the victim’s clothing stretched, torn, or ripped, grab marks or
    abrasions on her ankles, legs, and wrists, more injuries, and multiple sexual
    31
    assaults rather than the one. McCann conceded that, even in a group attack, some
    assailants might only strike minor glancing blows.
    D. The Motions Judge’s Decision
    Judge Weisberg rejected appellants’ IPA and Brady claims.          As to the
    former, the motions judge found that appellants had “not come close to
    demonstrating actual innocence” because the witness recantations on which
    appellants relied were not credible.    Beyond that, the judge also found “not
    particularly persuasive” the expert opinion testimony that Fuller likely was beaten
    by only one or a very few assailants, and appellants’ argument that the similarities
    between the murder of Fuller and McMillan’s murder of A.M. proved that
    McMillan was Fuller’s sole assailant.
    Turning to appellants’ Brady claims, the motions judge concluded there was
    no reasonable probability that the undisclosed evidence would have changed the
    outcome of the trial. This was so for three basic reasons: First, the judge noted,
    Ammie Davis’s hearsay accusation against James Blue “was almost certainly
    inadmissible,” and, in any event, it was “thoroughly discredited” and would not
    have convinced the jury to disbelieve the numerous eyewitness accounts of an
    attack by a large group of young men. “Not one of the approximately 400 other
    32
    witnesses interviewed by the government mentioned James Blue as a possible
    perpetrator,” the judge pointed out, “either alone or with others.”
    Second, the judge reasoned, the evidence pertaining to James McMillan was
    not material because no witness put him in the alley during the attack, and because
    even if he was present then, “it would not prove anything” about appellants since
    McMillan could have been a participant in the attack with them or merely a
    bystander. “For the ‘McMillan evidence’ to be material in the Brady sense,” the
    judge added, “he would have had to have committed the crime by himself or with
    Merkerson to the exclusion of the petitioners, and that possibility flies in the face
    of all the evidence.”
    Third, the judge found the undisclosed impeachment evidence to be of little
    significance even when viewed cumulatively. While Kaye Porter’s admission that
    she lied about hearing Alston’s confession, at Eleby’s request, could have been
    used to impeach Porter and Eleby, the nondisclosure was not material because
    Porter was a “relatively minor” witness at trial and Eleby was extensively
    impeached at trial with her prior inconsistent statements and her admitted lies
    before the grand jury. Similarly, Eleby was cross-examined at trial about her use
    of PCP and additional evidence on that score would not have made a difference.
    33
    Alibi testimony contradicting Alston’s claim that someone other than appellants
    was present in the park likewise would have been of little help to appellants, the
    judge concluded, particularly since the alibi “may or may not have been truthful.”19
    Lastly, the judge acknowledged that Maurice Thomas was “an important
    eyewitness because he was able to identify several of the [appellants] and had no
    apparent bias or motive to fabricate,” and he thought it “at least arguable” that the
    government should have disclosed that Thomas’s aunt did not recall his telling her
    that he had just seen someone attacked in the alley. Nevertheless, finding inter
    alia that Thomas testified convincingly at trial despite being cross-examined
    extensively, and that his aunt’s denial could be explained by Thomas’s testimony
    that she told him to forget what he had seen,20 the judge concluded that even if
    Thomas had been impeached by his aunt’s statement, “no juror would have
    concluded that he was making it all up.”
    19
    Citing Wu v. United States, 
    798 A.2d 1083
    , 1089-90 (D.C. 2002), the
    judge also held that appellants were procedurally barred from raising a Brady
    claim based on the government’s non-disclosure of alibis offered by witnesses
    whom Alston or Bennett claimed were present during the murder, because the trial
    judge had ruled that the government did not have to disclose such evidence and
    appellants did not appeal that ruling.
    20
    The judge also cited Goren’s impression, recorded in his contemporaneous
    case notes, that Thomas’s aunt was “a bit of an alcoholic.”
    34
    III. Analysis of Appellants’ Brady Claims
    A. Brady and the Applicable Standard of Review
    Appellants invoke a constitutional duty of governmental disclosure in
    criminal cases that the Supreme Court recognized in Brady v. Maryland21 over two
    decades before their trial: “The Due Process Clause of the Fifth Amendment
    requires the prosecution to disclose to the defense, upon request, material
    evidence—including impeachment evidence—that is favorable to the accused.”22
    The purpose of this duty “is not to displace the adversary system as the primary
    means by which truth is uncovered, but to ensure that a miscarriage of justice does
    not occur.”23 The failure to disclose materially favorable evidence constitutes a
    due process violation “irrespective of the good faith or bad faith of the
    prosecution”24 and without regard to whether the evidence was actually known by
    21
    
    373 U.S. 83
    , 87 (1963).
    22
    Miller v. United States, 
    14 A.3d 1094
    , 1106 (D.C. 2011). It is now clear
    that the suppression of materially favorable evidence is a violation of due process
    “regardless of [defense] request.” Kyles v. Whitley, 
    514 U.S. 419
    , 433 (1995)
    (citing United States v. Bagley, 
    473 U.S. 667
    , 682, 685 (1985)).
    23
    
    Bagley, 473 U.S. at 675
    .
    24
    
    Brady, 373 U.S. at 87
    .
    35
    the individual prosecutor, or merely by “others acting on the government’s behalf
    in the case, including the police.”25
    “To     determine    on   appeal   whether   the     government,   through   its
    representatives in the trial court, has violated its obligations under Brady, we
    consider: (1) whether the information in question is favorable to the accused; (2)
    whether this information was possessed and suppressed by the government, either
    willfully or inadvertently; and (3) whether that information was material” to guilt
    or punishment.26 Appellants have the burden of proving a Brady violation.27 In
    this case, although we think it may be doubted whether some of the undisclosed
    evidence in question was truly favorable to appellants, we need not linger over
    such doubts.      The primary and dispositive question with respect to all of
    appellants’ Brady claims is the question of materiality.
    Evidence is material within the meaning of Brady “if there is a reasonable
    probability that, had the evidence been disclosed to the defense, the result of the
    25
    
    Kyles, 514 U.S. at 437
    .
    26
    Vaughn v. United States, 
    93 A.3d 1237
    , 1254 (D.C. 2014) (internal
    quotation marks omitted).
    27
    Mackabee v. United States, 
    29 A.3d 952
    , 959 (D.C. 2011).
    36
    proceeding would have been different.”28 Materiality is “not a sufficiency of the
    evidence test.”29 Rather, evidence is material if it “could reasonably be taken to
    put the whole case in such a different light as to undermine confidence in the
    verdict.”30 Brady materiality must be assessed in terms of the cumulative effect of
    all suppressed evidence favorable to the defense, not on the evidence considered
    item by item.31 The cumulative effect of a collection of suppressed evidence may
    undermine confidence in the outcome of the trial even where each piece of
    evidence, viewed in isolation, would be insufficient. Of course, just as the trial
    court did, “[w]e evaluate the tendency and force of the undisclosed evidence item
    by item; there is no other way. We evaluate its cumulative effect for purposes of
    materiality separately and at the end of the discussion[.]”32
    28
    
    Miller, 14 A.3d at 1115
    (quoting 
    Bagley, 473 U.S. at 682
    ).
    29
    
    Kyles, 514 U.S. at 434
    .
    30
    
    Id. at 435.
          31
    
    Id. at 421.
          32
    
    Kyles, 514 U.S. at 436
    n.10.
    37
    Some past decisions of this court have reviewed a trial court’s ruling on
    Brady materiality for “reasonableness.”33 Our more recent cases, following the
    reasoning of the dissent in Farley v. United States,34 have questioned the aptness of
    that standard.35 As Judge Ruiz pointed out in her Farley dissent, the Supreme
    Court has consistently reviewed Brady rulings de novo,36 and a de novo standard of
    review “is consistent with the origin of the Brady materiality test, which is derived
    from the prejudice prong for ineffective assistance of counsel—an inquiry which
    33
    E.g., Davies v. United States, 
    476 A.2d 658
    , 661 (D.C. 1984) (“Where, as
    here, the trial court has determined that asserted Brady material would not have
    materially affected the verdict, the reviewing court is limited to a determination of
    whether that decision was reasonable. United States v. Agurs, 
    427 U.S. 97
    , 114
    (1976). An independent review is precluded. 
    Id. It cannot
    be said that the trial
    court’s ruling on the Brady-based new trial motion was unreasonable.”).
    34
    
    767 A.2d 225
    , 233 (D.C. 2001) (Ruiz, J., dissenting).
    35
    See Zanders v. United States, 
    999 A.2d 149
    , 162 (D.C. 2010); Watson v.
    United States, 
    940 A.2d 182
    , 187 (D.C. 2008); Powell v. United States, 
    880 A.2d 248
    , 254-55 (D.C. 2005); see also 
    Miller, 14 A.3d at 1120
    ; 
    id. at 1129
    n.11 (Fisher,
    J., dissenting).
    36
    See 
    Farley, 767 A.2d at 233
    (“No other conclusion can be reached from
    the Supreme Court’s opinions in Kyles, Bagley, Wood [v. Bartholomew, 
    516 U.S. 1
    (1995)] or Strickler [v.Greene, 
    527 U.S. 263
    (1999)], all of which exhaustively
    review the evidence, without expressing a deferential standard or, in fact, affording
    any deference to the lower courts’ determinations.”) (footnotes omitted). This
    seems to be one of the respects in which Agurs, the case that this court cited in
    Davies as mandating a deferential “reasonableness” standard of review, has been
    superseded.
    38
    the [Supreme] Court has held presents a mixed question of law and fact.”37
    Consequently, without resolving the issue of the proper standard of review, we
    latterly have “avoided applying the lesser ‘reasonableness’ standard[] where we
    have been able to conclude instead that even under de novo review, no material
    violation occurred.”38
    Notwithstanding our general adherence to stare decisis, we are not obligated
    “to follow, inflexibly, a ruling whose philosophical basis has been substantially
    undermined by subsequent Supreme Court decisions.”39          We think the proper
    approach is to recognize that a pure “reasonableness” standard of review is
    imprecise and does not meet the needs of the due process inquiry at stake in Brady
    cases. It is more accurate and appropriate to say, as we and other courts have said,
    that whether appellants have established a violation of Brady is a mixed question
    of fact and law.40       “In that circumstance, we review the trial court’s legal
    conclusions on a de novo basis and its factual findings under the clearly erroneous
    37
    
    Farley, 767 A.2d at 233
    .
    38
    
    Zanders, 999 A.2d at 162
    .
    39
    Frendak v. United States, 
    408 A.2d 364
    , 379 n.27 (D.C. 1979).
    40
    
    Miller, 14 A.3d at 1120
    ; see also 
    Farley, 767 A.2d at 234
    n.6 (Ruiz, J.,
    dissenting) (citing federal cases).
    39
    standard.”41 Materiality—defined as whether the government’s failure to disclose
    exculpatory evidence undermines our confidence in the verdict—is, in the end, a
    legal conclusion.42 Therefore, while we defer in this case to the motions judge’s
    assessments of credibility, evaluations of the weight of the evidence and the
    inferences to be drawn therefrom, and findings of historical fact, so long as they
    have record support, we respect, but we do not accord comparable deference to, the
    judge’s determination of the ultimate question of Brady materiality. With due
    appreciation for the fact-bound nature of that ultimate question, we must review it
    de novo on appeal.
    Pursuant to the foregoing principles, we now proceed to discuss the
    significance of the undisclosed evidence at issue in this appeal—first on an item-
    by-item basis, and then cumulatively.
    41
    
    Id. (quoting United
    States v. Joseph, 
    996 F.2d 36
    , 39 (3d Cir. 1993)
    (alteration omitted); accord 
    Vaughn, 93 A.3d at 1254
    .
    42
    Whether we choose to characterize materiality as a question of law or of
    “ultimate fact” is of little moment. See 
    Miller, 14 A.3d at 1120
    n.32 (“We also
    generally review de novo so-called findings of ‘ultimate fact’ . . . , since they are
    really conclusions of law.”).
    40
    B. The Witnesses in the Alley
    The statements of Watts, Luchie, and Murphy had the potential to advance
    appellants’ single-perpetrator theory.43 The groans heard by Watts and Luchie tend
    to show that Fuller was still alive between 5:30 and 5:45 p.m. And the fact that
    Luchie saw both garage doors closed, while one of the doors was open when
    William Freeman came by around 6:00 p.m. and discovered Fuller’s body, could
    be taken to suggest that the attack was then-occurring and that the true killer(s)
    opened one of the doors and fled in the interim. If the attack was in progress when
    Watts, Luchie, and Murphy walked by the garage, then as Goren acknowledged, it
    could not have been committed by a large group of people.
    As the government argues, if Fuller was being assaulted when Watts,
    Luchie, and Murphy passed next to the garage, one might think they would have
    heard more noise; the fact that they heard only the sounds of groans would seem to
    imply that the attack was over by then and that Fuller’s assailants were gone.
    Moreover, Luchie might have been mistaken in recalling that both garage doors
    were closed (Watts and Murphy did not say that), and even if they were, there was
    43
    Appellants contend that one, two, or at most three people killed Mrs.
    Fuller, but for ease of discussion, we shall refer to their view of the case as the
    single-perpetrator theory.
    41
    time for someone unknown to open one of the doors and depart before Freeman
    arrived and found Fuller’s body. Despite these considerations, we agree with
    appellants that the alley witness evidence has potential weight in a cumulative
    materiality analysis.44
    C. James McMillan Evidence
    The government had reason to suspect James McMillan of having
    participated in Fuller’s murder. He was a violent criminal prone to assaulting and
    robbing vulnerable women in the area; he was seen in the alley shortly after
    Fuller’s murder, acting suspiciously and concealing an object under his coat; he
    fled when the police arrived; and James Campbell and Christopher Taylor
    identified him as having joined in the attack (though Campbell’s hearsay
    identification could not have been introduced in evidence at appellants’ trial,
    Taylor presumably would have denied or disavowed it had he been asked, and their
    identifications of McMillan would not have supported a single-perpetrator theory).
    That McMillan committed a similarly heinous sexual assault and murder some
    years later only heightens the suspicion of his involvement. The parties disagree,
    44
    See Manson v. Brathwaite, 
    432 U.S. 98
    , 116 (1977) (“[E]vidence with
    some element of untrustworthiness is customary grist for the jury mill.”).
    42
    however, as to whether the evidence of McMillan’s other crimes is relevant to the
    Brady analysis.
    1. The October 1984 Robberies
    The parties disagree as to whether evidence of the two robberies McMillan
    committed in October 1984 would have been admissible at trial. Appellants and
    the government agree that the robberies did not amount to “reverse Drew
    evidence,” i.e., “evidence of a recent similar crime with a distinct modus
    operandi—which the defendant could be shown not to have committed.”45 The
    two robberies, in which the perpetrator attacked the victims, robbed them, and then
    fled without causing further harm, do not share a sufficiently “distinct modus
    operandi” with the assault on Fuller to justify the inference that the same person
    must have committed all three crimes.
    Appellants contend, however, that evidence of the robberies committed by
    McMillan would have been admissible in support of a third-party perpetrator
    45
    Bruce v. United States, 
    820 A.2d 540
    , 543 (D.C. 2003) (quoting Newman
    v. United States, 
    705 A.2d 246
    , 253 (D.C. 1997)).
    43
    defense under Winfield v. United States.46 Setting aside for the time being the
    separate question of whether evidence fairly implicating McMillan in the attack on
    Fuller would have raised sufficient doubts about appellants’ participation in the
    attack to show a Brady violation, we think appellants are correct that McMillan’s
    robberies would have been admissible in support of such a defense.
    “Winfield evidence” is evidence offered to show that someone other than the
    defendant committed the crime. For such evidence to be admissible,
    there must be proof of facts or circumstances which tend
    to indicate some reasonable possibility that a person
    other than the defendant committed the charged offense.
    The focus of the standard is not on the third party’s guilt
    or innocence, but on the effect the evidence has upon the
    defendant’s culpability, and in this regard it need only
    tend to create a reasonable doubt that the defendant
    committed the offense.[47]
    46
    
    676 A.2d 1
    (D.C. 1996) (en banc). On the distinction between reverse
    Drew evidence and Winfield evidence, see 
    Bruce, 820 A.2d at 543-45
    .
    “Admissibility under the Winfield standard . . . is broader” than under the standard
    for reverse Drew evidence. 
    Id. at 545.
          47
    
    Winfield, 676 A.2d at 4
    (internal quotation marks omitted). There is “no
    requirement that the proffered evidence must prove or even raise a strong
    probability that someone other than the defendant committed the offense.” 
    Id. (quoting Johnson
    v. United States, 
    552 A.2d 513
    , 517 (D.C. 1989)).
    44
    Winfield evidence is not limited to proof of the third party’s motive and “practical
    opportunity” to commit the crime;48 it also may include evidence that the third
    party committed “another crime like the one before the court.”49 The crimes “need
    not be identical” for such evidence to be admissible, if “the totality of the
    circumstances demonstrates a reasonable probability that the same person
    committed both offenses.”50 Conversely, “the trial court should exclude Winfield
    evidence if it “is too remote in time and place, completely unrelated or irrelevant to
    the offense charged, or too speculative with respect to the third party’s guilt.’”51
    And even if the proffered Winfield evidence satisfies the threshold requirement of
    relevance, the trial court has discretion to exclude it based on a determination that
    its marginal probative value is substantially outweighed by the risk of unfair
    prejudice, confusion of the jury, or similar considerations.52 However, “[c]lose
    48
    
    Winfield, 676 A.2d at 5
    .
    49
    
    Bruce, 820 A.2d at 543
    (quoting 
    Newman, 705 A.2d at 254
    ).
    50
    
    Bruce, 820 A.2d at 544
    (alteration and citation omitted).
    51
    Thomas v. United States, 
    59 A.3d 1252
    , 1264 (D.C. 2013) (quoting Resper
    v. United States, 
    793 A.2d 450
    , 460 (D.C. 2002)).
    52
    
    Winfield, 676 A.2d at 5
    .
    45
    questions of admissibility should be resolved in favor of inclusion, not
    exclusion.”53
    Here, we think it reasonable to conclude that McMillan’s commission of two
    other robberies in October 1984 would have corroborated the other evidence that
    he joined in the October 1 attack on Fuller. The government principally argues
    that the probative value of that corroboration would have been minimal, and
    substantially outweighed by the risk of unfair prejudice, because there were few
    similarities between the two robberies and Fuller’s murder.54           We disagree,
    inasmuch as the three crimes all involved violent assaults and robberies of middle-
    aged women who were walking alone on the street, and all took place in the same
    neighborhood in a span of less than a month. That the attack on Fuller was far
    more vicious and severe than the other two robberies does not negate these points
    of similarity. We therefore are satisfied that a trial judge would be safely within
    her discretion in admitting the evidence of McMillan’s robberies under Winfield;
    accordingly, they are relevant to the Brady materiality analysis.
    53
    
    Bruce, 820 A.2d at 544
    (citing 
    Winfield, 676 A.2d at 6-7
    ).
    54
    The government also argues that McMillan would not still have been
    hanging around the garage when the police arrived had he been one of the
    assailants, but this is not entirely persuasive; appellants Catlett and Overton were
    still in the park across the street when the police came to the scene.
    46
    2. The 1992 Murder of A.M.
    We reach a different conclusion with respect to McMillan’s murder of A.M.
    seven years after appellants’ trial. Because evidence of this murder obviously
    could not have been presented at appellants’ trial, it is not relevant to whether the
    government violated its Brady obligations. A Brady violation cannot be predicated
    on the government’s failure to do the impossible and disclose evidence that does
    not yet exist. McMillan’s murder of A.M. likewise has no bearing on the question
    of the materiality of any evidence that the government actually did withhold from
    the defense. This is so because materiality under Brady turns on a retrospective
    assessment of whether a past trial might have had a different outcome had
    available evidence not been kept from the defendant—not on whether new,
    previously unobtainable evidence not kept from the defendant might lead to a
    different result in a new trial. There are other procedures available for exploring
    whether new evidence calls for a new trial—for example, the procedures of the
    Innocence Protection Act that appellants employed in this case—but they are
    subject to different standards; simply put, “Brady is the wrong framework” to use
    for obtaining post-conviction relief based on new evidence.55
    55
    Dist. Attorney’s Office for the Third Judicial Dist. v. Osborne, 
    557 U.S. 52
    , 69 (2009) (holding that the Brady right of pretrial disclosure does not provide a
    post-conviction right of access to evidence for newly available DNA testing).
    47
    D. Ammie Davis’s Accusation of James Blue
    There is reason to doubt that Ammie Davis’s accusation of James Blue
    would have carried significant weight with the jury, given her lack of credibility
    and the complete absence of other evidence associating Blue in any way with
    Fuller’s murder. But we need not examine that question. Davis, having been
    murdered prior to the start of appellants’ trial, was unavailable to testify at it. Her
    out-of-court statements accusing Blue did not fall within any exception to the rule
    against hearsay. Hence her statements would have been inadmissible as evidence
    that Blue killed Fuller. Evidence that is inadmissible cannot be material for Brady
    purposes unless there is a reasonable probability that its disclosure would have
    resulted in a different trial outcome because it is likely to have led to the discovery
    of other, admissible evidence favorable to the defense.56 No such probability has
    56
    See Wood v. Bartholomew, 
    516 U.S. 1
    , 6 (1995) (holding that undisclosed
    polygraph results were not material where they were “inadmissible under state law,
    even for impeachment purposes,” and the possibility that disclosure “might have
    led respondent’s counsel to conduct additional discovery that might have led to
    some additional evidence that could have been utilized” was “mere speculation”);
    United States v. Morales, 
    746 F.3d 310
    , 314-15 (7th Cir. 2014) (finding the
    majority view in the federal courts of appeals, that inadmissible evidence may be
    material if it could have led to the discovery of admissible evidence, to be “more
    consistent” with Wood than “a rule that restricts Brady to formally admissible
    evidence”) (citing cases); United States v. Derr, 
    990 F.2d 1330
    , 1335-36 (D.C. Cir.
    1993) (rejecting Brady claim based on government’s failure to disclose
    inadmissible hearsay of declarant who would be unavailable to testify at trial).
    48
    been shown here. Appellants have not demonstrated any likelihood that they
    would have located and obtained helpful testimony from the girlfriend Davis
    mentioned, or that they would have discovered any other admissible evidence
    implicating Blue in Fuller’s murder.
    Appellants, citing Chambers v. Mississippi,57 contend that due process
    would have required the trial court to admit Davis’s statement for its truth in spite
    of the rule against hearsay. We disagree. As the Supreme Court has explained, the
    “fundamental” right of an accused in a criminal case “to present witnesses in his
    own defense”58 is not “an unfettered right to offer testimony that is incompetent,
    privileged, or otherwise inadmissible under standard rules of evidence.”59
    “Evidentiary rules excluding evidence from criminal trials violate the
    constitutional right to present a defense only if they ‘infringe upon a weighty
    interest of the accused and are arbitrary or disproportionate to the purposes they are
    57
    
    410 U.S. 284
    (1973).
    58
    
    Id. at 302.
          
    59 Taylor v
    . Illinois, 
    484 U.S. 400
    , 410 (1988).
    49
    designed to serve.’”60
    In Chambers, the Supreme Court confronted two such dubious evidentiary
    rules. The defendant in that case was charged with murder. At trial, he sought to
    prove that another man named McDonald had confessed to the crime orally and in
    writing, but he was stymied by two Mississippi rules of evidence. First, he was
    prevented from cross-examining McDonald (who had repudiated his written
    confession) by Mississippi’s common law “voucher” rule prohibiting a party from
    impeaching his own witness.61 In addition, he was unable to present the testimony
    of three credible witnesses to whom McDonald had confessed orally, because
    Mississippi applied its hearsay exception for declarations against interest only to
    statements against pecuniary interest, and not to statements against the declarant’s
    penal interest, regardless of their trustworthiness.62
    60
    Heath v. United States, 
    26 A.3d 266
    , 276 (D.C. 2011) (quoting Holmes v.
    South Carolina, 
    547 U.S. 319
    , 324 (2006)); see, e.g., United States v. Scheffer, 
    523 U.S. 303
    , 309, 316-17 (1998) (rejecting a constitutional challenge to a rule
    excluding lie detector results because the rule was not arbitrary or disproportionate
    to the ends it was designed to serve).
    61
    
    Chambers, 410 U.S. at 291-92
    .
    62
    
    Id. at 292-94,
    299.
    50
    The Supreme Court reversed Chambers’s conviction, holding that “under the
    facts and circumstances of this case the rulings of the trial court [in combination]
    deprived Chambers of a fair trial” by unjustifiably interfering with his fundamental
    right to defend himself.63 As the Court explained, while an accused exercising that
    right “must comply with established rules of procedure and evidence designed to
    assure both fairness and reliability in the ascertainment of guilt and innocence,”64
    the evidentiary restrictions imposed on Chambers were not designed or
    implemented to serve those purposes.
    The rule that a party may not impeach his own witness was, in the Court’s
    words, “a remnant of primitive English trial practice” that “bears little present
    relationship to the realities of the criminal process” in the present day.65 The rule
    “has been condemned,” the Court added, “as archaic, irrational, and potentially
    destructive of the truth-gathering process.”66      In addition, while the Court
    acknowledged that the “materialistic limitation” of the declaration-against-interest
    hearsay exception to statements against pecuniary interest “might serve some valid
    63
    
    Id. at 303.
          64
    
    Id. at 302.
          65
    
    Id. at 296.
          66
    
    Id. at 296
    n.8.
    51
    state purpose by excluding untrustworthy testimony” in some cases, “[t]he hearsay
    statements involved in this case were originally made and subsequently offered at
    trial under circumstances that provided considerable assurance of their
    reliability.”67 Each confession was made “spontaneously to a close acquaintance
    shortly after the murder had occurred”; “each one was corroborated by some other
    evidence in the case”; “each confession here was in a very real sense self-
    incriminatory and unquestionably against [the declarant’s] interest”; and “[f]inally,
    if there was any question about the truthfulness of the extrajudicial statements,
    McDonald was present in the courtroom and was under oath” and subject to cross-
    examination and observation by the jury.68 Given also that McDonald’s out-of-
    court confessions were “critical” to Chambers’s defense, implicating his
    “constitutional rights directly affecting the ascertainment of guilt,” the Court
    concluded that Mississippi’s “hearsay rule may not be applied mechanistically to
    defeat the ends of justice.”69
    67
    
    Id. at 299-300.
          68
    
    Id. at 300-01.
    “McDonald’s presence,” the Court observed, “deprives the
    State’s argument for retention of the penal-interest rule of much of its force.” 
    Id. at 301
    n.21.
    69
    
    Id. at 302.
                                               52
    It is plain that this case is nothing like Chambers.          Davis’s statement
    implicating Blue in Fuller’s murder would have been excluded at appellants’ trial
    pursuant to a routine and uncontroversial application of the basic rule against
    hearsay; unlike the statements against penal interest in Chambers, it did not even
    arguably fall within any of the recognized hearsay exceptions for statements “made
    under circumstances that tend to assure reliability and thereby compensate for the
    absence of the oath and opportunity for cross-examination.”70 The Supreme Court
    cast no doubt in Chambers on the constitutionality of excluding such ordinary
    hearsay evidence when offered by the defendant in a criminal trial.           On the
    contrary, the Court acknowledged that “perhaps no rule of evidence has been more
    respected or more frequently applied in jury trials than that applicable to the
    exclusion of hearsay,” and it agreed that criminal defendants “must comply” with
    such established rules.71 As the Court said, the rule against hearsay is
    grounded in the notion that untrustworthy evidence
    should not be presented to the triers of fact. Out-of-court
    statements are traditionally excluded because they lack
    the conventional indicia of reliability: they are usually
    not made under oath or other circumstances that impress
    the speaker with the solemnity of his statements; the
    declarant’s word is not subject to cross-examination; and
    70
    
    Id. at 299.
          71
    
    Id. at 302.
                                                53
    he is not available in order that his demeanor and
    credibility may be assessed by the jury.[72]
    Every one of the Court’s enumerated reasons why hearsay is excluded as
    untrustworthy applies to Davis’s statement.       In short, the exclusion of that
    statement on hearsay grounds would not have been arbitrary or disproportionate to
    the purposes that the rule against hearsay is designed to serve. It therefore would
    not have violated appellants’ due process rights.      The Constitution does not
    displace the hearsay rule in this case.73
    72
    
    Id. at 298.
          73
    Appellants argue that if the government had disclosed Davis’s statement
    when the prosecutors first learned of it in August 1985, her “transience and drug
    use could have caused defense counsel to procure an admissible statement from her
    in the event she became unavailable.” We do not see how appellants would have
    accomplished this. Depositions to preserve testimony for trial are disfavored in
    criminal cases, and the burden is on the party seeking a deposition to demonstrate
    “exceptional circumstances” necessitating it. See Super. Ct. Crim. R. 15 (a);
    United States v. Kelley, 
    36 F.3d 1118
    , 1124 (D.C. Cir. 1994). Among other things,
    this normally calls for a showing that the witness will be unavailable to testify at
    trial, 
    id. at 1125—a
    showing appellants could not have made prior to Davis’s
    death.
    Appellants suggest they could have asked Davis to prepare a statement about
    Blue’s involvement in Fuller’s murder that would have been admissible at trial in
    case of her unavailability through another witness under the hearsay exception for
    past recollection recorded. See Mitchell v. United States, 
    368 A.2d 514
    , 517-18
    (D.C. 1977). But appellants could not have satisfied the requirements for
    admission under that exception because such a statement would not have been
    made at or near the time of the putative assault by Blue on Fuller, and because it
    does not appear appellants could have called a witness who would have been able
    (continued…)
    54
    Arguably the fact that Davis accused Blue of complicity in Fuller’s murder
    would have been admissible for the non-hearsay purpose of showing that the
    government’s investigation of the crime was (in this one respect at least) less than
    diligent.     Suppressed evidence of an inadequate investigation is potentially
    material.74    Although the government is correct that Davis’s statement might
    nevertheless have been excluded as more prejudicial than probative, it is enough to
    say that the trial judge would have had discretion to admit it for this limited
    purpose. On the other hand, if the evidence had been admitted for this limited
    purpose, we think its impact would have been negligible absent any showing either
    that more diligent investigation of Blue would have been productive, or that a lack
    of thoroughness went beyond the belated follow-up with Ammie Davis and
    infected the investigation in other ways so as to undermine the charges against
    (continued…)
    to vouch for the accuracy of the statement from personal knowledge of that event.
    See 
    id. 74 See
    Kyles v. Whitley, 
    514 U.S. 419
    , 445 (1995) (holding statements
    material because they “would have raised opportunities to attack . . . the
    thoroughness and even the good faith of the investigation”).
    55
    appellants. Neither showing would have been made.75 And evidence that the
    government performed a less than thorough investigation of the allegation against
    Blue would have had little likelihood of persuading the jury that a different
    person—i.e., James McMillan—was the true killer.            To the contrary, the
    government would have been able to demonstrate that the investigation was indeed
    quite a thorough one overall, involving over four hundred interviews, and that
    McMillan’s culpability was examined.
    Appellants further argue that even if Davis’s statement itself was
    inadmissible, it might have led them to discover admissible evidence that could
    have affected the outcome of the trial in their favor.76 However, appellants have
    not identified any such evidence that might affect our evaluation of the materiality
    75
    We presume, of course, that the jury would obey a limiting instruction
    and not consider Davis’s statement as evidence that Blue himself murdered Fuller.
    See, e.g., Knight v. Georgetown Univ., 
    725 A.2d 472
    , 483 (D.C. 1999).
    76
    Cf. United States v. Bagley, 
    473 U.S. 667
    , 683 (1985) (“[T]he reviewing
    court may consider directly any adverse effect that the prosecutor’s failure to
    respond [to a Brady request] might have had on the preparation or presentation of
    the defendant’s case.”); Miller v. United States, 
    14 A.3d 1094
    , 1108 (D.C. 2011)
    (“An important purpose of the prosecutor’s obligations under Brady is to allow
    defense counsel an opportunity to investigate the facts of the case and, with the
    help of the defendant, craft an appropriate defense.”) (internal quotation marks
    omitted); Boyd v. United States, 
    908 A.2d 39
    , 61 (D.C. 2006) (“[T]he prosecutor
    must make the materiality determination . . . with a view to the need of defense
    counsel to explore a range of alternatives in developing and shaping a defense.”).
    56
    of the undisclosed evidence at issue. We note that appellants did not proffer that
    timely disclosure of Davis’s statement would have enabled them to find and
    present favorable testimony from the girlfriend who supposedly could have
    corroborated Davis’s accusation against Blue.
    In sum, the evidence concerning James Blue contributes to the cumulative
    materiality of the undisclosed evidence only to the very limited extent it would
    have had value in demonstrating a slip-up in the government’s investigation.
    E. Impeachment Evidence
    We agree with Judge Weisberg that the withheld impeachment evidence,
    whether considered piece-by-piece or in conjunction with the other undisclosed
    evidence, had little prospect of changing the result at trial. Although “impeaching
    information does not have a lesser standing in the context of the government’s
    Brady disclosure obligations” than affirmatively exculpatory information,77 it “can
    be immaterial . . . if it is cumulative and the witness has already been impeached
    77
    Vaughn v. United States, 
    93 A.3d 1237
    , 1254 (D.C. 2014).
    57
    by the same kind of evidence.”78         That principle applies to some of the
    impeachment evidence at issue here.
    The fact that Kaye Porter initially lied to the police at Carrie Eleby’s behest,
    to corroborate Eleby’s story that she had not seen the assault and that Alston had
    confessed his involvement to her, could have been used to impeach both Porter and
    Eleby. But Porter provided evidence at trial only against appellant Catlett—she
    testified to a conversation in which she asked him about Fuller’s murder, and he
    responded that he “didn’t do nothing to her” and that “all he did was kick her and
    somebody else stuck the pole up in her” because “she wasn’t acting right.” This
    testimony was impeached with Porter’s grand jury testimony that Catlett simply
    told her he “didn’t do nothing to that lady.” Moreover, the other evidence against
    Catlett was second only to that against Rouse:        among other things, Alston,
    Bennett, Eleby, and Thomas all testified that they saw Catlett physically attack
    Fuller; Montgomery saw him in the park before the murder and watched him cross
    the street and head toward Fuller; Thomas also recalled hearing Catlett tell
    someone why he and Fuller’s other assailants killed her; and Catlett had no alibi.
    78
    Watson v. United States, 
    940 A.2d 182
    , 187 (D.C. 2008); see also
    Williams v. United States, 
    881 A.2d 557
    , 562-63 (D.C. 2005).
    58
    Eleby too was impeached with her prior false statements to the police and to
    the grand jury and contradicted by other witnesses, and as described above, her
    inability to remember and keep her facts straight also undermined her credibility.
    It is hard to see why the additional impeachment would have made a difference to
    the jury’s assessment of Eleby’s credibility.
    The undisclosed evidence of Eleby’s extensive PCP use was also of little
    consequence. Eleby’s claim that she smoked PCP for the first and last time on
    October 1 was unbelievable on its face. Jacobs testified that she saw Eleby use
    PCP at other times, and even if the jury disbelieved most of Jacobs’s testimony, it
    had no reason to doubt her assertion, otherwise unrelated to the case, that her close
    friend was a drug user.
    We likewise are not persuaded that disclosure of the evidence contradicting
    Alston’s assertion that Lamont Bobbitt was one of the persons present in the park
    and alley at the time of Fuller’s murder (i.e., the evidence supporting Bobbitt’s
    alibi, which several witnesses corroborated in testimony before the grand jury)
    would have made a difference with respect to the jury’s evaluation of Alston’s
    credibility. The jury was willing to acquit Harris even though Alston testified that
    he was an active participant in the murder. We do not see how knowing that one
    59
    other person (who was not another defendant at trial) whom Alston named as
    present was not actually there would have swayed the jury.
    Finally, although Maurice Thomas’s testimony may have been an important
    factor in the jury’s verdicts, his aunt’s statement (that she did not recall Thomas
    having told her about the attack on Fuller) was unlikely to have discredited
    Thomas in any significant way. One of the strengths of his trial testimony was his
    candid acknowledgement of what he could not remember, namely whether or not
    Christopher Turner and Smith were present in the alley. Because he never claimed
    excellent recall of every detail of what he saw, it was not significant that his aunt
    could not corroborate a relatively minor part of his testimony. And if, as Thomas
    testified, she had told him not to report what he saw, she had every reason to deny
    their conversation when she spoke to the police. Moreover, the jury was willing to
    convict even where it did disbelieve Thomas, for it found Overton guilty despite
    Thomas’s claim that he was not in the alley.
    In sum, we think none of the impeachment evidence was material
    individually, and that it adds little to any cumulative materiality analysis.
    60
    F. Cumulative Materiality of the Undisclosed Evidence
    We may turn now to the question of the cumulative materiality of the
    undisclosed exculpatory and impeachment evidence. To reiterate, the question is
    whether there exists a reasonable probability that the result of appellants’ trial
    would have been different had the evidence been disclosed to the defense. We
    have concluded that, in addressing this question, our primary focus must be on the
    potential value to the defense of (1) the testimony of Watts and Luchie that they
    walked past the garage where Fuller lay dying at around 5:30 p.m. and heard
    groans coming from inside, and that the garage doors were closed; and (2) the
    identification of James McMillan as the person seen acting suspiciously in the
    vicinity of the garage sometime after the murder. While we do not ignore the
    potential value to the defense of the impeachment evidence and the limited non-
    hearsay use that appellants could have made of Davis’s accusation of James Blue,
    we think the contribution of that evidence would have been negligible for the
    reasons we have already given.
    Appellants argue that the undisclosed evidence was valuable not because it
    exculpated any of them directly, but because it would have enabled them to present
    an alternative single-perpetrator theory of the crime (with expert witness support)
    as a counter-narrative to the prosecution’s case: Watts and Luchie may have
    61
    overheard the assault being committed by only a limited number of persons—
    perhaps only one—rather than the large group described by the prosecution
    witnesses; and McMillan, given his presence on the scene and criminal history,
    plausibly may have been one of that limited number of assailants, though no
    prosecution witness named him as such.         The physical (as opposed to the
    eyewitness) evidence of the attack adduced at trial arguably supported, or at least
    was not inconsistent with, a single-perpetrator theory, and there was some other
    evidence at trial to corroborate it.79
    The fact remains that the government presented the testimony of several
    eyewitnesses, including two participants who admitted their own guilt, who did
    implicate appellants in a group attack. No witness to the attack who testified at
    trial disputed their overall description of how the crime was committed, and the
    eyewitnesses were corroborated by evidence of incriminating admissions by some
    of the appellants. It is true that the prosecution witnesses contradicted themselves
    and each other on various points, and some of them had potential motives to lie or
    79
    Notably, perhaps, William Freeman testified at trial that throughout his
    day at 8th and H Streets, working as a street vendor, he never saw a large group of
    young people in the area, never saw anyone running towards or away from the
    vicinity of the garage, and never heard any shouts coming from the area of the
    garage.
    62
    other problems with their testimony. Moreover, no fingerprint, DNA, or other
    forensic evidence implicated any defendant.80 But the undisclosed evidence (other
    than the impeachment evidence that we have discounted) did not take advantage of
    those weaknesses; it did not, for example, contradict the government witnesses’
    accounts, demonstrate their bias, or incorporate contrary forensic evidence pointing
    to perpetrators other than the defendants on trial.
    Nor, we conclude, did the undisclosed evidence truly provide substantial
    support for a single-perpetrator theory of the crime, or any theory that excluded
    appellants as the perpetrators. The groans, undoubtedly Fuller’s, that Watts and
    Luchie heard coming from the garage between 5:30 and 5:45 p.m. did not mean the
    assault was still occurring or that any assailant was still present. On the contrary,
    the fact that Watts and Luchie heard nothing else and saw no signs of any activity
    more likely indicated that the assault was over and that the assailants were gone.
    This was entirely consistent with the government’s evidence, and provided no
    reason to doubt it, inasmuch as Fuller left her house around 4:30 p.m. and all of the
    witnesses described a fast-moving event lasting, in all probability, no more than a
    80
    In 1985, when this case was tried, DNA analysis was in its infancy. In
    2011, the trial court ordered DNA testing of swabs taken from Fuller’s body, a
    semen sample from her pantyhose, various articles of her clothing, and a metal
    pole found at the scene, but the tests did not result in a derivable DNA profile.
    63
    few minutes. Luchie’s observation that both garage doors were closed shortly
    before Freeman found one of them open would have raised a question, but it too
    does not mean anyone was still in the garage with Fuller when Luchie passed by.
    It surely would not have been enough to turn a jury that found the government’s
    witnesses credible, as this jury did. It is far more likely, in our view, that the jury
    would have believed that Luchie was mistaken, or that someone came upon the
    scene and opened the garage door in the interval between Luchie’s departure and
    Freeman’s arrival, than that the jury would have thought it plausible that all the
    government’s witnesses were lying and that Luchie had stumbled upon an assault
    in progress.
    The evidence regarding James McMillan perhaps could have led the jury to
    suspect that he participated in the attack on Fuller, notwithstanding the fact that he
    was not charged and no eyewitness said he was involved. Alternatively, the jury
    might have suspected that McMillan arrived on the scene only after Watts and
    Luchie departed (but before Freeman arrived), and that he and his companion
    Merkerson looked in the garage—providing an explanation for Luchie’s and
    Freeman’s observations of the garage door that did not rely on the supposition that
    64
    the assailants were still present when Luchie was there.81 But we think the jury,
    even if it had heard from Watts and Luchie, would have had no substantial reason
    to suspect McMillan was the sole perpetrator of Fuller’s murder, or that he was one
    of only a few assailants. Even if he was involved in it, his involvement was
    entirely consistent with the government’s evidence that a large group including
    Alston, Bennett, and appellants committed the crime; McMillan simply could have
    been another member of that group. (Indeed, had there been a focus on McMillan
    at trial, the jury presumably would have learned what the government did to
    investigate his involvement, and perhaps also that Christopher Taylor had
    implicated him as a participant in the large group attack.)
    Moreover, a theory that McMillan could have been the sole perpetrator of
    the attack on Fuller, or only one of two or three perpetrators, would have been
    exceedingly implausible and difficult for the jury to accept—and not only because
    of the dearth of any evidence inculpating him. To think McMillan could have
    committed the crime himself, the jury would have had to think not only that all the
    government witnesses were lying or mistaken about every defendant at trial, but
    81
    It is not implausible that McMillan heard about the attack and decided to
    look in out of curiosity; nor that he carried away something from the garage,
    explaining his suspicious behavior.
    65
    that Alston and Bennett, the government’s two cooperating witnesses, were
    innocent even though they had each pleaded guilty to homicide and continued to
    admit their guilt. That would not have been a plausible claim to make to the jury.
    It would have been about as daunting for the defense to contend that McMillan
    committed the crime with just one or two accomplices. Those accomplices would
    surely have to have been Alston and Bennett (which begs the question of
    Merkerson’s involvement), but if they were going to admit their own guilt and
    cooperate as part of their plea bargains, there was no apparent reason why they
    would have shielded McMillan.82
    82
    A far more plausible contention that the attack on Fuller was committed
    by a small group (one that excluded the defendants on trial) would have been that
    Alston and Bennett were the sole perpetrators. The government’s withholding of
    evidence did not prevent appellants from raising such a defense at trial. Virtually
    all the evidence appellants have marshaled against the prosecution’s claim of a
    large group attack—e.g., the expert testimony of Dr. Callery and McCann,
    Freeman’s trial testimony that throughout his day at 8th and H Streets, he never
    saw a group of young people congregating in the park or engaging in any attack—
    was available to the defense in 1985. In addition, Alston and Bennett’s plea
    bargains furnished them an identifiable motive to falsely implicate others, and
    every prosecution witness was vulnerable to impeachment or other challenge on
    cross-examination in one way or another. Perhaps the testimony of Watts and
    Luchie would have lent additional support to a theory that Alston and Bennett were
    the only perpetrators; but for the reasons we have discussed, it would have been
    slight support at most.
    66
    Our conclusion is the same for each appellant individually. Overton and
    Christopher Turner point to the fact that the jury found it most difficult to convict
    them. It is true that in some ways the evidence against these two was weaker than
    that against their co-defendants. Maurice Thomas could not remember whether
    Christopher Turner was in the alley and affirmatively denied seeing Overton there,
    and Vincent Gardner did not contradict these two defendants’ alibis the way he did
    those of other defendants.     But Overton, Christopher Turner, and the other
    appellants are similarly situated with respect to the way in which appellants
    contend the undisclosed evidence regarding the number of assailants and
    McMillan’s possible involvement could have undermined the government’s case
    against them. The evidence either would have provided significant ammunition in
    support of a single-perpetrator defense or not (and we conclude not). It had no
    bearing on whether any one individual defendant was part of a large group attack.
    This case is not like Kyles or Miller, the two cases on which appellants
    principally rely. In those cases, there was no dispute as to how the crime occurred,
    only a dispute as to the identity of the perpetrator. In each case, the Brady
    violation was based on the suppression of substantial evidence that directly
    67
    undercut the prosecution’s proof of identity and supported the most plausible third-
    party perpetrator claim by the defense.83
    Here,   the   undisclosed   evidence      (aside   from the   inconsequential
    impeachment evidence) would not have directly contradicted the government’s
    witnesses or shown them to be lying, and it did not tend to show that any given
    appellant was misidentified. Rather, what is at issue is the basic structure of how
    the crime occurred. This makes the burden on appellants to show materiality quite
    difficult to overcome, because it requires a reasonable probability that the withheld
    evidence (in its entirety, and however appellants would have developed it) would
    have led the jury to doubt virtually everything that the government’s eyewitnesses
    said about the crime. It would be different, for example, if the government had
    suppressed evidence of the kinds of allegations Alston and Bennett made in their
    later recantations. That, if believed, would have given the jury a basis on which to
    83
    In Kyles, the prosecution concealed statements by eyewitnesses to a
    murder that contradicted their identification of the defendant, and statements by the
    putative alternative perpetrator (along with other evidence) suggesting he had
    framed the defendant and was himself guilty of the crime. See 
    514 U.S. 419
    , 441-
    49 (1995). In Miller, where the defendant was charged with assault with intent to
    kill, timely disclosure of the Brady material—an eyewitness’s grand jury testimony
    indicating that the perpetrator of a shooting was left-handed (unlike the
    defendant)—would have helped the defendant establish the guilt of an alternative
    suspect. Miller v. United States, 
    14 A.3d 1094
    , 1116 (D.C. 2011).
    68
    doubt the government’s entire case. The same might be true if the government had
    suppressed credible and admissible evidence directly contradicting the accounts of
    the crime provided by the eyewitnesses.         Here, however, the sum of the
    undisclosed evidence did not rise to that level of significance. We agree with the
    motions judge that, even if all that evidence had been disclosed in a timely and
    appropriate fashion, appellants have not demonstrated a reasonable probability that
    the result of their trial would have been different. The withheld evidence cannot
    “reasonably be taken to put the whole case in such a different light as to undermine
    confidence in the verdict.”84
    IV. Analysis of Appellants’ IPA Claims
    The IPA85 allows a convicted person to move for a new trial or vacatur of his
    conviction at any time “on grounds of actual innocence based on new evidence.”86
    “Actual innocence” means “the person did not commit the crime of which he or
    she was convicted.”87 “New evidence,” as relevant here, is evidence that was “not
    84
    
    Kyles, 514 U.S. at 435
    .
    85
    D.C. Code §§ 22-4131 to 4135 (2012 Repl.).
    86
    
    Id. § 22-4135
    (a).
    87
    
    Id. § 22-4131
    (1).
    69
    personally known and could not, in the exercise of reasonable diligence, have been
    personally known to the movant at the time of the trial.”88 In hearing a claim
    brought under the IPA, the court “may consider any relevant evidence,” but must
    consider, inter alia,
    (A) The new evidence; (B) How the new evidence
    demonstrates actual innocence; (C) Why the new
    evidence is or is not cumulative or impeaching; [and] (D)
    If the conviction resulted from a trial, and if the movant
    asserted a theory of defense inconsistent with the current
    claim of innocence, the specific reason the movant
    asserted an inconsistent theory at trial.[89]
    A defendant is entitled to a new trial if he can show his actual innocence by a
    preponderance of the evidence.90 If he can demonstrate his actual innocence by
    clear and convincing evidence, the court must vacate the conviction with
    prejudice.91
    88
    
    Id. § 22-4131
    (7)(A).
    89
    
    Id. § 22-4135
    (g)(1).
    90
    
    Id. § 22-4135
    (g)(2).
    91
    
    Id. § 22-4135
    (g)(3).
    70
    We review the denial of a motion to vacate a conviction or for a new trial
    under the IPA for abuse of discretion.92 In doing so, “we must give great deference
    to the trial court’s role as the trier of fact on the ultimate issue of ‘actual
    innocence’ under the IPA, and thus we apply the clearly erroneous standard of
    review to the trial judge’s rejection of alleged newly discovered evidence offered
    to prove ‘actual innocence.’”93
    Appellants’ claims of actual innocence depend on the credibility of the
    recantations by four witnesses who testified against them at trial, and in particular
    on the recantations by Alston and Bennett. The motions judge concluded that
    appellants “have not come close to demonstrating actual innocence” because he
    found the recantations to be “not worthy of belief.”              Such a credibility
    determination, made after the judge had the opportunity to hear the recanting
    92
    Richardson v. United States, 
    8 A.3d 1245
    , 1248 (D.C. 2010); see also
    Mitchell v. United States, 
    80 A.3d 962
    , 971 (D.C. 2013) (“To the extent that the
    statute affords the trial court discretion in its application of the IPA, we review for
    abuse of discretion.”) (quoting Veney v. United States, 
    936 A.2d 811
    , 822 (D.C.
    2007), as modified, 
    936 A.3d 809
    (D.C. 2007)).
    93
    
    Richardson, 8 A.3d at 1249
    (internal citation omitted); see also D.C.
    Code § 17-305 (2012 Repl.) (setting out the standard of review of bench verdicts).
    71
    witnesses’ live testimony and observe their demeanor, may be overturned only if
    “it is wholly unsupported by the evidence.”94
    As the motions judge noted, witness recantations in general are “properly
    viewed with great suspicion” because they are “very often unreliable and given for
    suspect motives,”95 among other reasons. Alston and Bennett’s recantations in
    94
    Godfrey v. United States, 
    454 A.2d 293
    , 301 (D.C. 1982); see also
    Johnson v. United States, 
    33 A.3d 361
    , 371 (D.C. 2011) (Where a motion for a
    new trial is based on the recantation of a witness, “[i]f the trial court determines
    that the recantation is not credible, that determination ends the inquiry.”) (citation
    omitted); Bell v. United States, 
    871 A.2d 1199
    , 1201 (D.C. 2005) (same, under the
    IPA). This accords with the usual rule in an appeal from a bench trial that “[a]n
    appellate court will not redetermine the credibility of witnesses where, as here, the
    trial court had the opportunity to observe their demeanor and form a conclusion.”
    In re S.G., 
    581 A.2d 771
    , 775 (D.C. 1990) (quoting WSM, Inc. v. Hilton, 
    724 F.2d 1320
    , 1328 (8th Cir. 1984)); accord David v. United States, 
    957 A.2d 4
    , 8 (D.C.
    2008) (“This court will not ‘substitute its judgment for that of the fact-finder when
    it comes to assessing the credibility of a witness . . . based on factors that can only
    be ascertained after observing the witness testify.’”) (quoting Robinson v. United
    States, 
    928 A.2d 717
    , 727 (D.C. 2007)).
    95
    Dobbert v. Wainwright, 
    468 U.S. 1231
    , 1233-34 (1984); see also, e.g.,
    Meade v. United States, 
    48 A.3d 761
    , 766 (D.C. 2012) (“It has long been
    established that recanting affidavits and witnesses are looked upon with the utmost
    suspicion by the courts.”) (quoting United States v. Kearney, 
    682 F.2d 214
    , 219
    (D.C. Cir. 1982); internal quotation marks and brackets omitted); V.C.B. v. United
    States, 
    37 A.3d 286
    , 291 (D.C. 2012) (“[C]ourts often view recantations of
    previous accusatory statements with suspicion or skepticism, in part because
    witnesses offering recantations are often facing radically different pressures than
    . . . they were at the time of the initial trial.”) (internal citations and quotation
    marks omitted); 
    Godfrey, 454 A.2d at 300
    n.26 (“[W]itnesses may recant for
    numerous reasons that have nothing to do with furthering truth or justice.”).
    72
    particular were suspect, the judge observed, for to accept them “one must begin by
    suspending one’s disbelief that a person would plead guilty to murder (Alston) and
    manslaughter and robbery (Bennett) and accept a sentence of many years in prison,
    all based on lies the police pressured them to tell against themselves and their close
    friends who, based on those lies, would be convicted and spend the rest of their
    lives in prison.” Beyond that, the judge explained the evidentiary basis for his
    refusal to credit Alston and Bennett as follows:
    The court had an opportunity to hear their
    testimony under oath, observe their demeanor, compare it
    to their demeanor on their videotaped interrogations on
    November 29, 1984 (Alston), and February 6, 1985
    (Bennett), review their trial testimony under oath, and
    compare their testimony to the testimony of all the other
    witnesses at trial who placed some or all of the
    petitioners at the scene. In this context, the current
    testimony of Alston and Bennett that they were not at 8th
    and H Streets on October 1, 1984, and that they were
    forced by the police to say they were there and to name
    the others who were there is nothing short of
    preposterous. The scene in the alley on October 1, 1984,
    was crowded and chaotic. Alston and Bennett may have
    gotten some facts wrong and may have left certain things
    out or distorted the truth to minimize their own
    involvement or to protect others, but the basic facts
    implicating these petitioners and describing a crime
    perpetrated by a large group were corroborated by too
    many other witnesses not to be believed. The notion that
    Alston and Bennett were not present and made it all up
    cannot be credited when juxtaposed with their videotaped
    statements, their guilty pleas, Alston’s admissions to
    other witnesses, Alston’s trial testimony and Bennett’s
    grand jury and trial testimony. Both witnesses were
    73
    extensively cross examined at trial by ten seasoned
    defense counsel over the course of several days about the
    many discrepancies and inconsistencies in their
    respective versions of events. It is exceedingly unlikely
    that any juror would have concluded that Alston and
    Bennett were not on the scene or that they were not
    accurately reporting at least most of what they saw,
    heard, and did that day. Their motives for now coming
    forward cannot be known. Both are now out of prison
    and no longer seeking release from the parole board,
    where their current lack of remorse might be held against
    them. Back in their communities, perhaps even this
    many years later they are still burdened with guilt from
    having benefitted themselves by sending their friends to
    prison. Whatever their current motivation may be, the
    court does not credit their recantations, and their attempt
    at exculpation does not help the petitioners meet their
    burden of proving actual innocence.
    In short, the judge evaluated the recantations of Alston and Bennett in light of the
    entire evidentiary record, taking into account their demeanor both on the witness
    stand and during their allegedly coerced confessions, and weighing their
    recantations against their previous sworn testimony and other evidence of their
    guilt and petitioners’ guilt.96 We have no basis on which to overturn the judge’s
    finding that the recantations were incredible.
    96
    It should be noted that the judge credited the detectives and prosecutors
    who denied having coerced witness testimony. In that connection, the judge did
    not ignore the expert opinion testimony of Dr. Leo. But as the judge pointed out,
    the most this expert testimony could show was that the interrogators in this case
    employed techniques that heightened the risk of a false confession; it did not
    establish that the confessions were false.
    74
    We also perceive no error in the judge’s finding that the purported
    recantations of Montgomery and Jacobs were worthless. We need not belabor this
    point. As to Jacobs, the judge fairly concluded that her recantation was unreliable
    because it “did not indicate with any specificity or clarity just which parts of her
    prior account were untrue.”97 As for Montgomery, who disavowed his recanting
    affidavit and reaffirmed the truth of his trial testimony, the judge certainly did not
    err in concluding that his testimony at the 2012 hearing lent no support to
    petitioners’ IPA claim.
    Without the discredited recantations, appellants’ remaining new evidence
    was clearly not enough to overcome the government’s proof of their guilt and show
    their actual innocence by a preponderance of the evidence, let alone by clear and
    convincing evidence. Appellants argued that the “unrebutted scientific evidence,”
    i.e., the expert opinion testimony of Dr. Callery and McCann, showed them to be
    innocent. We agree with the motions judge that this does not qualify as “new
    evidence” under the IPA, because appellants, in the exercise of reasonable
    97
    
    Meade, 48 A.3d at 767
    . In addition to insisting that she lied about the
    petitioners at trial but did not remember anything she said, Jacobs also testified that
    she never went into the alley where Fuller was attacked. The judge found it
    striking, however, that “whenever [Jacobs] was asked if she saw any of the attack
    or the act of sodomy against Mrs. Fuller, Ms. Jacobs broke down sobbing just the
    way she did when she was confronted with that visual image at trial.”
    75
    diligence, could have presented such testimony at their trial.98 But even assuming
    otherwise, the motions judge had ample reason to discount the expert testimony
    proffered by appellants, for as he explained,
    neither Dr. Callery nor Mr. McCann could definitively
    state that Mrs. Fuller was attacked by one to three
    individuals as opposed to a larger group. While both
    testified that, in their opinion, it was more likely that a
    small number of individuals inflicted the injuries on Mrs.
    Fuller, both admitted that it was possible that a greater
    number of persons were involved.[99] Given the court’s
    rejection of the recantations and the other trial evidence
    pointing to an attack by ten or more assailants,
    petitioners’ “unrebutted scientific evidence,” even if it
    were new, is not particularly persuasive and does not
    begin to demonstrate that the petitioners are “actually
    innocent.”
    Finally, McMillan’s horrific murder of A.M. in 1992 may tend to make it
    more likely that he was involved in the attack on Fuller eight years earlier.
    Nevertheless, we agree with the motions judge that “these two brutal murders
    could not be characterized as signature crimes,” and that “[w]hatever may be said
    of the similarities between the two crimes, they certainly do not prove that James
    98
    See D.C. Code § 22-4131 (7); Bouknight v. United States, 
    867 A.2d 245
    ,
    254-56 (D.C. 2005).
    99
    Moreover, the medical examiner who testified in 1985 concluded that he
    could not say with specificity how many people attacked Fuller, a conclusion with
    which Dr. Callery agreed.
    76
    McMillan murdered Mrs. Fuller to the exclusion of [appellants], when all of the
    credible evidence points the other way.”
    V. Yarborough’s Claim of Ineffective Assistance of Counsel
    In the videotaped statement he gave following his arrest, appellant
    Yarborough admitted having been present at the alley and witnessing appellants’
    attack against Fuller, though he denied participating in the attack himself.
    Yarborough’s motion to suppress the videotaped statement as involuntary was
    denied, and the statement was introduced in evidence against him at trial. In his
    § 23-110 motion, Yarborough claimed that his trial counsel pursued suppression of
    his statement ineffectively, in violation of his duties to Yarborough under the Sixth
    Amendment, because he neglected to investigate Yarborough’s mental disabilities
    and rely on them as additional grounds for finding the statement involuntary. In
    rejecting this claim, the motions judge concluded that Yarborough failed to show
    either that his counsel’s performance was deficient or that the alleged deficiency
    prejudiced him at trial. We find it unnecessary to reach the question of deficient
    performance, because we agree with the motions judge that Yarborough has not
    carried his burden of showing the requisite likelihood of prejudice.
    77
    A. Background
    1. Yarborough’s Statements to Police
    On October 4, 1984, three days after Fuller’s murder, Yarborough was
    interviewed as a witness to the incident by Detectives McGinnis and Sanchez.
    Their questions and Yarborough’s answers were recorded in an eight-page
    typewritten statement.100 In this initial interview, Yarborough told the detectives
    he was present at 8th and H Streets when a number of his friends (including several
    of the appellants here) decided to rob a lady crossing the street there. Yarborough
    said he did not join them or participate in the attack, but he watched the others
    follow the lady to the alley. He said he walked away after hearing the lady’s
    screams.
    Yarborough was not arrested until the morning of December 9, 1984. On
    that occasion, he again waived his Miranda rights and agreed to be questioned by
    Detectives McGinnis and Sanchez. His interrogation culminated in an hour-long
    100
    At the outset, Yarborough acknowledged understanding that he was not
    under arrest and was free to leave at any time, and he waived his Miranda rights.
    When asked whether he could read and write, Yarborough answered, “I can write
    but I can’t read real good.” Yarborough then was asked whether he would like
    Detective Sanchez to read his statement over to him, and he requested this be done.
    Yarborough proceeded to sign every page of the statement and initial every one of
    his answers.
    78
    videotaped statement. At the outset of that statement, Yarborough confirmed that
    he understood and had waived his Fifth Amendment rights in writing, that no
    promises had been made to him in return for his statement, and that no force had
    been used against him.101 Then, beginning with McGinnis’s open-ended request to
    “tell us everything you know about” the death of Fuller, Yarborough described
    how he saw appellants and others attack, rob, hit, and stomp Fuller in the alley at
    8th and H Streets, sodomize her with a pole just outside the garage, and then drag
    her into the garage there.      Although Yarborough continued to deny having
    participated in this attack in any way (which was contrary to other evidence the
    police had obtained since his earlier interview), he now admitted his presence at
    the scene from start to finish. A version of Yarborough’s videotaped statement,
    redacted to eliminate his identification of several of his co-defendants, was
    admitted in evidence against him at trial and played for the jury.
    2. Yarborough’s Suppression Motion
    Prior to trial, Yarborough moved to suppress his videotaped statement. His
    sole contention at the suppression hearing was that the detectives had employed
    101
    McGinnis asked Yarborough if he was injured. Yarborough said, “not
    really,” and went on to explain that he had a “bad leg” from an injury he had
    received before that day.
    79
    threats and physical abuse to coerce him into waiving his rights and admitting he
    was present when Fuller was murdered. The detectives denied it. Yarborough’s
    only evidence of mistreatment—he did not take the stand and testify to it—was the
    fact that, after his statement was videotaped, the police took him to the hospital,
    where he was treated for pain and swelling in his left knee and released. The
    hospital records reflected that Yarborough reported his leg had been injured in the
    course of his arrest. In his videotaped statement, however, Yarborough said he had
    hurt his leg sometime before he was arrested, and Detective McGinnis testified that
    Yarborough told him he had injured his knee playing sports. After taking this
    evidence and viewing the videotape, the trial judge found that Yarborough did not
    sustain his knee injury during his interrogation, that his claims of abuse were
    unsubstantiated, and that he voluntarily waived his Miranda rights.
    On direct appeal, Yarborough argued that the trial judge erred in denying his
    motion without taking into consideration “his age, education, and experience with
    the criminal justice system.”102 Because Yarborough had presented no evidence
    with respect to those factors, we held that the trial court “properly based its
    decision upon the important factors brought to its attention,” and that “[u]nder the
    102
    Catlett v. United States, 
    545 A.2d 1202
    , 1207 (D.C. 1988).
    80
    totality of the circumstances, the trial court’s conclusion had substantial support in
    the evidence.”103 We affirmed the denial of Yarborough’s motion to suppress.
    3. The Hearing on Yarborough’s Ineffective Assistance Claim
    Yarborough took the stand for the first time at the 2012 hearing on
    appellants’ post-conviction motions. He did so in part to present evidence relevant
    to his ineffective assistance of counsel claim (namely, that he took special
    education classes in junior high and high school and could not read well), but
    principally to assert his innocence and reiterate, this time in his own words, his
    previous claim that the detectives coerced him by means of physical violence and
    threats of violence into waiving his rights and falsely incriminating himself.
    Contradicting the statements he gave to the police on October 4 and December 9,
    1984 (and other evidence adduced at trial), Yarborough asserted that he spent the
    afternoon and evening of October 1, 1984, at his girlfriend’s house, was not at 8th
    and H Streets when Fuller was attacked, and did not witness the crime at all.104
    103
    
    Id. at 1209.
          104
    Yarborough’s girlfriend at the time, Chandera Hill, corroborated his alibi
    but was impeached with her 1985 grand jury testimony that she did not remember
    what she or Yarborough were doing on the day of the murder.
    81
    Yarborough claimed that the eight-page question-and-answer statement of
    October 4 was a total sham: The police, he said, wrote it in advance of his
    interview without his knowledge, and Detective McGinnis directed him to initial
    virtually every line and sign every page while covering it with his hand to prevent
    Yarborough from reading it.
    As to the December 9 videotaped statement, Yarborough claimed it was the
    product of extensive physical abuse by Detective Sanchez, threats of violence by
    both detectives, and prolonged coaching by McGinnis. Yarborough testified that
    before the videotaping, in response to his initial refusal to waive his Miranda
    rights, Sanchez threw him across the table, screamed that he could not write “no”
    on the waiver form, and then slammed him back into his chair.            Only then,
    Yarborough said, did he agree to waive his rights. Next, Yarborough testified,
    after he insisted he knew nothing about Fuller’s murder, Sanchez threw him around
    the room and into a filing cabinet (allegedly injuring his left knee), dragged him to
    a bathroom and flushed his by now bloodied head in the toilet bowl. At one point,
    the detective dramatically ripped off his own t-shirt and threatened to kill
    Yarborough if he did not confess. McGinnis allegedly warned Yarborough that
    Sanchez had killed two other people for lying, expressed the hope that Yarborough
    would not be the third, and read him several statements about the attack on Fuller
    82
    to instruct him what he needed to say. During the videotaping that followed this
    abusive treatment, Yarborough testified, Sanchez menacingly held a slapjack in his
    hand to keep him in line while McGinnis signaled to him with his eyes to guide his
    testimony and help him avoid straying from the script. (The videotape does not
    reveal any such behavior on the part of either detective, or any signs that
    Yarborough had been mistreated or injured.)
    What he said on tape about the crime, Yarborough testified, came in part
    from what McGinnis told him to say (off-camera, just before the videotaping
    commenced), and in part from his own imagination. Because he did not admit to
    having participated in the robbery and assault of Fuller, Yarborough expected to be
    released after the videotaping.105
    Both detectives testified at the hearing and contradicted Yarborough’s
    account of his interrogations. They denied ever physically abusing Yarborough or
    threatening him in any way, telling him he could not invoke his rights, feeding him
    information, or directing him what to say or sign. The detectives averred that
    105
    He remained in custody, however, and was taken to the hospital for his
    leg injury. He testified that he told hospital personnel that the police had beaten
    him.
    83
    Yarborough himself provided the information in his eight-page statement on
    October 4; McGinnis described Yarborough as being able to understand and
    answer their questions in a responsive, “cogent” manner. The detectives
    acknowledged that on December 9, when they questioned Yarborough after he
    waived his rights and before he agreed to give a videotaped statement, they
    sometimes yelled at him, accused him of lying, and told him he would be better off
    if he would just tell the truth. They admitted playing a “good cop/bad cop” routine
    in which Sanchez pretended to be enraged, McGinnis ushered him out of the room,
    and Sanchez then banged on the door, demanding to be let back in. At one point,
    Sanchez either pretended to or actually did tear off his t-shirt for dramatic effect.
    But Yarborough did not appear to be intimidated by these tactics. He continued to
    deny any personal involvement in the attack on Fuller, and he adhered to certain
    details of his story that the detectives questioned (notably, whether he received
    money taken from Fuller, which Yarborough firmly denied).
    Two witnesses at the 2012 hearing testified in support of Yarborough’s
    claim that an investigation by his trial counsel of his cognitive impairments would
    have yielded support for a motion to suppress his videotaped statement on
    voluntariness grounds.    First, Dr. Michael O’Connell, a forensic psychologist,
    testified that Yarborough had an adjusted full scale I.Q. score of 69.5, placing him
    84
    at the high end of the range for mild mental retardation, and that Yarborough’s low
    scores on the Gudjonsson Suggestibility Scales indicated he was more suggestible
    than 99% of the population.106 Dr. O’Connell opined that a person with these
    characteristics would struggle in an interrogation setting because he would tend to
    overemphasize short-term benefits at the expense of long-term consequences and
    be acquiescent and eager to please his interrogators.107
    Second, Chandera Hill (Yarborough’s girlfriend in 1984) testified that she
    regularly helped Yarborough with his homework, often doing it for him because he
    had trouble with reading, comprehension, and pronunciation.108 She also testified
    that Yarborough’s trial counsel spoke to her but never asked her about
    Yarborough’s I.Q., comprehension, reading, or homework abilities.
    In rejecting Yarborough’s ineffective assistance claim, and concluding that
    evidence of his mental impairments would not have changed the outcome of the
    106
    There also was documentary evidence, referenced in Yarborough’s
    presentencing report, that a psychological evaluation performed in May 1984
    found Yarborough to be “functioning intellectually in the mentally deficient to
    borderline range.”
    107
    Yarborough “didn’t do badly,” however, on a test to determine whether
    he understood his Miranda rights.
    108
    Yarborough was sixteen years old in 1984.
    85
    motion to suppress his videotaped statement, the motions judge found, inter alia,
    that Yarborough’s testimony at the hearing was “patently incredible,” and that the
    evidence did not “bear out any of [his] extraordinary claims” of physical abuse,
    threats, and other misconduct by the detectives who obtained his statements.109
    The judge credited the detectives’ testimony to the contrary. In addition, and
    “most importantly,” the judge found that
    [Yarborough’s] demeanor on the videotape of his
    interrogation shows him to be entirely relaxed,
    spontaneous, and in no distress. Many of the things
    Yarborough said on the videotape seem unlikely when
    compared with other evidence, but there is no indication
    that the facts he chose to include came from the police or
    from any source other than him. For example, when the
    detectives tried to get him to admit that he received
    money that was part of the proceeds of the robbery of
    Mrs. Fuller, he adamantly insisted that the two dollars he
    received from petitioner Catlett was a loan that came
    from other money Catlett had in his pocket, not from the
    proceeds of the robbery.
    In sum, the judge found that Yarborough’s videotaped statement
    was not the statement of a helpless mentally vulnerable
    young man being fed facts by the police and parroting
    them back to please his interrogators; it was the voluntary
    admission of a conniving youthful offender trying to
    distance himself as far as possible from the crime while
    109
    Yarborough does not challenge these factual findings on appeal.
    86
    not denying that he was there . . . . No amount of
    psychological testing or social science research was
    likely to convince the court that this false exculpatory
    statement should be suppressed, particularly where the
    judge did not believe the defendant’s claim about
    physical coercion in the first place.
    B. Analysis
    A claim of ineffective assistance of counsel has two components:
    First, the defendant must show that counsel’s
    performance was deficient. This requires showing that
    counsel made errors so serious that counsel was not
    functioning as the “counsel” guaranteed the defendant by
    the Sixth Amendment. Second, the defendant must show
    that the deficient performance prejudiced the defense.
    This requires showing that counsel’s errors were so
    serious as to deprive the defendant of a fair trial, a trial
    whose result is reliable.[110]
    The performance and prejudice components of the ineffectiveness inquiry are
    mixed questions of law and fact.111 On appeal, we accept the motions judge’s
    findings of fact unless they lack evidentiary support, and we review the judge’s
    legal conclusions de novo.112
    110
    Strickland v. Washington, 
    466 U.S. 668
    , 687 (1984).
    111
    
    Id. at 698.
          112
    Cosio v. United States, 
    927 A.2d 1106
    , 1123 (D.C. 2007) (en banc).
    87
    As the Supreme Court has said, “there is no reason” for an appellate court to
    address both components of the ineffectiveness inquiry if it determines that the
    defendant has made an insufficient showing on one of them. “In particular, a court
    need not determine whether counsel’s performance was deficient before examining
    the prejudice suffered by the defendant as a result of the alleged deficiencies. . . .
    If it is easier to dispose of an ineffectiveness claim on the ground of lack of
    sufficient prejudice, which we expect will often be so, that course should be
    followed.”113     We think it appropriate to confine our discussion here to the
    prejudice component of Yarborough’s claim. We therefore shall assume, without
    deciding, that trial counsel performed deficiently in failing to investigate and learn
    of Yarborough’s mental limitations in anticipation of moving to suppress his
    videotaped statement as involuntary.114 The question then is whether it is likely
    that this failure of investigation was prejudicial to Yarborough.
    To satisfy the prejudice component of the ineffectiveness inquiry, a
    defendant’s burden is to show “a reasonable probability that, but for counsel’s
    113
    
    Strickland, 466 U.S. at 697
    .
    114
    It should be noted that Yarborough’s claim is that his statement was
    involuntary, not that he lacked the necessary understanding to waive his Fifth
    Amendment rights knowingly and intelligently.
    88
    unprofessional errors, the result of the proceeding would have been different.”115
    In this case, that necessary showing has multiple steps. First, Yarborough must
    show a reasonable probability that a competent attorney, having investigated and
    become aware of his intellectual limitations and susceptibility to police pressure
    and suggestion, would have relied on those facts as a basis for moving to suppress
    his videotaped statement as involuntary.116 Second, Yarborough must show that it
    is reasonably probable the trial court would have granted a motion to suppress
    based on this theory.117 And third, Yarborough also must show a reasonable
    probability that the jury’s verdict would have been different—that the jury would
    have acquitted him on at least some counts—had his statement been suppressed.118
    115
    
    Strickland, 466 U.S. at 694
    .
    116
    See 
    Cosio, 927 A.2d at 1132
    .
    117
    Howerton v. United States, 
    964 A.2d 1282
    , 1290 (D.C. 2009) (citing
    Taylor v. United States, 
    603 A.2d 451
    , 459 (D.C. 1992)).
    118
    See Kimmelman v. Morrison, 
    477 U.S. 365
    , 375 (1986) (holding that
    where a claim of ineffectiveness is predicated on defense counsel’s failure to
    litigate an evidence suppression motion competently, the defendant must prove that
    the motion “is meritorious and that there is a reasonable probability that the verdict
    would have been different absent the excludable evidence in order to demonstrate
    actual prejudice”).
    89
    We shall focus on the first two of these steps.119
    At the pretrial suppression hearing, the government bore the burden of
    proving that Yarborough’s videotaped statement was voluntary by a preponderance
    of the evidence.120      “The test for determining the voluntariness of specific
    statements is whether, under the totality of the circumstances, the will of the
    suspect was overborne in such a way as to render his confession the product of
    coercion.”121 The presence of official compulsion—“coercive police activity” or
    “police overreaching”—is “a necessary predicate to the finding that a confession is
    not ‘voluntary’ within the meaning of the Due Process Clause.”122 That said, “[i]n
    determining whether a defendant’s will was over-borne in a particular case, the
    119
    We think Yarborough has made the showing required in the third step, a
    reasonable probability that the jury would have acquitted him had it not had his
    videotaped statement to consider.            The evidence introduced at trial of
    Yarborough’s complicity in the attack on Fuller without that statement was not
    overwhelming. Although Alston and Thomas implicated him in the attack, Bennett
    testified that Yarborough remained in the park when the group accosted Mrs.
    Fuller, and Montgomery only remembered seeing Yarborough there after the
    murder, not before. The importance of Yarborough’s videotaped statement is
    suggested by the fact that it was the last thing the jury asked to see before returning
    its first round of verdicts, in which it found Yarborough guilty.
    120
    Graham v. United States, 
    950 A.2d 717
    , 735 (D.C. 2008) (citing, inter
    alia, Lego v. Twomey, 
    404 U.S. 477
    , 484 (1972)).
    121
    
    Id. at 735-36
    (internal quotation marks and brackets omitted).
    122
    
    Id. at 736
    (quoting Colorado v. Connelly, 
    479 U.S. 157
    , 166-67 (1986)).
    90
    Court has assessed the totality of all the surrounding circumstances—both the
    characteristics of the accused and the details of the interrogation.”123 Relevant
    personal characteristics include “the suspect’s age, education, prior experience
    with the law, and physical and mental condition”; “relevant details of the
    interrogation include its duration and intensity, the use of physical punishment,
    threats or trickery, and whether the suspect was advised of his rights.”124
    Because Yarborough’s intellectual limitations and suggestibility could have
    impaired his effective assertion of his rights and rendered him vulnerable to police
    coercion, they unquestionably were relevant to the voluntariness inquiry in this
    case. But that is not the end of the inquiry125; despite Yarborough’s cognitive
    123
    
    Id. at 736
    (quoting Schneckloth v. Bustamonte. 
    412 U.S. 218
    , 226
    (1973)).
    124
    Id.; see also, e.g., In re M.A.C., 
    761 A.2d 32
    , 36 (D.C. 2000) (recognizing
    that where “young persons” are involved, the factors bearing on voluntariness
    include “the juvenile’s age, experience, education, background and intelligence,
    the circumstances under which the statement was given, and whether the juvenile
    ‘has the capacity to understand the warnings given him, the nature of his Fifth
    Amendment rights, and the consequences of waiving those rights,’” as well as any
    “evidence of physical abuse, the length of the detention, the use of trickery, mental
    or emotional stability, mental capacity, and physical illness or injury”) (quoting
    Fare v. Michael C., 
    442 U.S. 707
    , 725 (1979)).
    125
    Cf. In re 
    M.A.C., 761 A.2d at 38-39
    (upholding determination that mildly
    mentally retarded fifteen-year-old’s confession was voluntary; “[a] low I.Q.,
    standing alone, will not render an otherwise voluntary and knowing confession
    (continued…)
    91
    weaknesses, there is insufficient evidence to show a reasonable probability that he
    actually was coerced into waiving his rights and providing the statement used
    against him. The evidence is to the contrary.
    First, the contention that Yarborough’s videotaped statement was the
    product of his intellectual limitations and consequent vulnerability to police
    suggestion is flatly inconsistent with Yarborough’s own testimony at the 2012
    hearing and what he apparently told his trial counsel in 1985—that the detectives
    coerced him into waiving his rights and making a false statement against his will
    by force and violence. This assertion by Yarborough means that his putative
    vulnerability to police suggestion had nothing to do with his waiver and statement.
    Indeed, so far as appears, Yarborough has never maintained that his statement and
    incriminating admissions were the product of undue suggestion or trickery by his
    interrogators, or of his own suggestibility, confusion, naïve desire to please the
    police, inability to appreciate the gravity of his situation, or the like. As the
    motions judge observed in his decision, Yarborough claimed “the police beat the
    (continued…)
    inadmissible. . . . [t]he youth’s intelligence, as measured by testing, is only one of
    many factors for consideration”); Robinson v. United States, 
    928 A.2d 717
    , 725-27
    (D.C. 2007) (holding videotaped confession voluntary notwithstanding defendant’s
    mild mental retardation).
    92
    statement out of him under circumstances that would have caused the strong as
    well as the weak to succumb to the pressure.” This is devastating to Yarborough’s
    alternative claim that his intellectual limitations could have persuaded the trial
    court to suppress his statement as involuntary, since it means the argument would
    have been vitiated and frustrated by Yarborough’s inability to support it with his
    own testimony.
    In addition, the other evidence in its totality refutes the claim that the
    detectives took advantage of Yarborough’s low intelligence and suggestibility to
    coerce his videotaped statement. That hour-long exchange with the detectives is
    itself compelling evidence otherwise. Whatever pressure Yarborough was under to
    confess his participation in the attack on Fuller, he did not yield to it. 126 Nor was
    he notably compliant in other respects.       As the motions judge pointed out,
    Yarborough did not acquiesce in the detectives’ effort to get him to admit that he
    received some of Fuller’s money from appellant Catlett after the murder. That a
    number of other details Yarborough provided about the assault were contrary to
    what the police had learned from other sources further undercuts the claim that
    126
    Indeed, that Yarborough professes to have believed he was going to be
    released after the videotaping because he had not admitted participating in the
    attack provides additional reason to conclude his statement was voluntary.
    93
    Yarborough was induced to spout what the detectives wanted to hear even though
    he did not know it to be true. In point of fact, Yarborough’s serious cognitive
    limitations themselves make it hard to credit the idea that his videotaped statement
    was the product of a rehearsal in which he learned the lines the detectives fed him;
    one would think the degree of concentration and memory required for that to
    succeed would have been beyond his mental capabilities.
    There is no indication of coercion or lack of voluntariness on the videotape.
    It can be seen that Yarborough is not handcuffed. He sits at a table, facing the two
    detectives. He has a can of soda to drink. The motions judge accurately described
    his demeanor as relaxed, spontaneous, and evincing no sign of distress or
    discomfort. Yarborough does not appear to be injured or tired. He was not
    deprived of sleep, nor had he been in custody for more than a few hours. He had
    been advised, repeatedly, of his Miranda rights, and he had agreed to waive them.
    There is no reason to doubt that he adequately understood his rights and what it
    meant to waive them.
    In short, due to his intellectual limitations, Yarborough may have been
    highly suggestible, compliant, and prone to making faulty judgments about his own
    best interests—but that does not mean the police obtained his videotaped statement
    94
    by taking advantage of those vulnerabilities.         The evidence to the contrary
    convinces us that there is no reasonable probability that a motion to suppress his
    statement as involuntary based on his intellectual limitations would have
    succeeded, or that competent counsel aware of Yarborough’s mental disabilities
    would have thought such a motion worth pursuing under the circumstances of this
    case. We therefore hold that Yarborough has not shown the necessary prejudice
    from his trial counsel’s failure to investigate his mental limitations to prevail on his
    claim of ineffective assistance of counsel.
    VI. Conclusion
    For the foregoing reasons, we affirm the order of the Superior Court denying
    appellants’ motions for relief from their convictions under D.C. Code §§ 22-4135
    and 23-110.
    So ordered.