State v. Schroeder , 305 Neb. 527 ( 2020 )


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    Nebraska Supreme Court Advance Sheets
    305 Nebraska Reports
    STATE v. SCHROEDER
    Cite as 
    305 Neb. 527
    State of Nebraska, appellee, v.
    Patrick W. Schroeder, appellant.
    ___ N.W.2d ___
    Filed April 17, 2020.    No. S-18-582.
    1. Sentences: Death Penalty: Appeal and Error. In a capital sentenc-
    ing proceeding, the Nebraska Supreme Court conducts an independent
    review of the record to determine if the evidence is sufficient to support
    imposition of the death penalty.
    2. Sentences: Aggravating and Mitigating Circumstances: Appeal and
    Error. When reviewing the sufficiency of the evidence to sustain the
    trier of fact’s finding of an aggravating circumstance, the relevant ques-
    tion for the Nebraska Supreme Court is whether, after viewing the evi-
    dence in the light most favorable to the State, any rational trier of fact
    could have found the essential elements of the aggravating circumstance
    beyond a reasonable doubt.
    3. ____: ____: ____. A sentencing panel’s determination of the existence
    or nonexistence of a mitigating circumstance is subject to de novo
    review by the Nebraska Supreme Court.
    4. Sentences: Death Penalty: Aggravating and Mitigating Circum­
    stances: Appeal and Error. In reviewing a sentence of death, the
    Nebraska Supreme Court conducts a de novo review of the record to
    determine whether the aggravating and mitigating circumstances support
    the imposition of the death penalty.
    5. Rules of Evidence. In proceedings where the Nebraska Evidence Rules
    apply, the admissibility of evidence is controlled by the Nebraska
    Evidence Rules; judicial discretion is involved only when the rules make
    discretion a factor in determining admissibility.
    6. Constitutional Law: Statutes: Appeal and Error. The constitutionality
    of a statute presents a question of law, which an appellate court indepen-
    dently reviews.
    7. Sentences: Death Penalty: Homicide: Aggravating and Mitigating
    Circumstances: Appeal and Error. Under Nebraska law, the death
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    STATE v. SCHROEDER
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    305 Neb. 527
    penalty is imposed for a conviction of murder in the first degree only in
    those instances when the aggravating circumstances existing in connec-
    tion with the crime outweigh the mitigating circumstances.
    8.   Trial: Rebuttal Evidence. Rebuttal evidence is confined to new mat-
    ters first introduced by the opposing party and limited to that which
    explains, disproves, or counteracts the opposing party’s evidence.
    9.   Sentences: Death Penalty: Aggravating and Mitigating Circum­
    stances: Evidence. In a death penalty case, a sentencing panel has the
    discretion to hear evidence to address potential mitigating circumstances
    regardless of whether the defendant presents evidence on that issue.
    10.   Sentences: Evidence. A sentencing court has broad discretion as to
    the source and type of evidence and information which may be used
    in determining the kind and extent of the punishment to be imposed,
    and evidence may be presented as to any matter that the court deems
    relevant to the sentence.
    11.   Sentences: Death Penalty: Aggravating and Mitigating Circum­
    stances: Evidence. In a death penalty case, a sentencing panel may
    permit the State to present evidence to contradict potential mitigators
    even though a defendant failed to present affirmative evidence.
    12.   Sentences: Death Penalty: Homicide. A sentencing order in a death
    penalty case must specify the factors the sentencing panel relied upon in
    reaching its decision and focus on the individual circumstances of each
    homicide and each defendant.
    13.   Constitutional Law: Sentences: Death Penalty: Aggravating and
    Mitigating Circumstances. The U.S. Constitution does not require the
    sentencing judge or judges to make specific written findings in death
    penalty cases with regard to nonstatutory mitigating factors.
    14.   Sentences: Aggravating and Mitigating Circumstances: Appeal and
    Error. The Nebraska Supreme Court will not fault a sentencing panel
    for failing to discuss a nonstatutory mitigating circumstance that it was
    not specifically asked to consider.
    15.   Death Penalty: Aggravating and Mitigating Circumstances. During
    the consideration of statutory mitigating factors in a death penalty case,
    the mere identification of a history of incarceration, without more,
    is insufficient to allege unusual pressures or influences or establish
    extreme mental or emotional disturbance.
    16.   Sentences: Homicide: Aggravating and Mitigating Circumstances:
    Judgments: Juries: Presentence Reports. When an offender has been
    convicted of first degree murder and waives the right to a jury determi-
    nation of an alleged aggravating circumstance, the court must order a
    presentence investigation of the offender and the panel must consider a
    written report of such investigation in its sentencing determination.
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    Nebraska Supreme Court Advance Sheets
    305 Nebraska Reports
    STATE v. SCHROEDER
    Cite as 
    305 Neb. 527
    17. Presentence Reports. A presentence investigation and report shall
    include, when available, any submitted victim statements and an analy-
    sis of the circumstances attending the commission of the crime and the
    offender’s history of delinquency or criminality, physical and mental
    condition, family situation and background, economic status, education,
    occupation, and personal habits.
    18. Presentence Reports: Probation and Parole. A presentence investiga-
    tion and report may include any matters the probation officer deems
    relevant or the court directs to be included.
    19. Constitutional Law: Criminal Law: Sentences: Right to Counsel. An
    accused has a state and federal constitutional right to be represented by
    an attorney in all critical stages of a criminal prosecution which can lead
    to a sentence of confinement.
    20. Right to Counsel: Waiver. A defendant may waive the right to counsel
    so long as the waiver is made knowingly, voluntarily, and intelligently.
    21. Constitutional Law: Right to Counsel. The same constitutional provi-
    sions that provide a defendant the right to counsel also guarantee the
    right of the accused to represent himself or herself.
    22. Attorney and Client. The right to self-representation plainly encom-
    passes certain specific rights of the defendant to have his voice heard,
    including that the pro se defendant must be allowed to control the orga-
    nization and content of his own defense.
    23. Sentences: Death Penalty: Attorney and Client: Aggravating and
    Mitigating Circumstances: Evidence: Waiver. Control of the orga-
    nization and content of a defense may include a waiver of the right to
    pre­sent mitigating evidence during sentencing in a death penalty case.
    24. Criminal Law: Sentences: Death Penalty: Appeal and Error. Because
    a death sentence is different from any other criminal penalty and no sys-
    tem based on human judgment is infallible, the Nebraska Supreme Court
    has taken, and should continue to take, the extra step to ensure fairness
    and accuracy with the imposition of the death penalty.
    25. Criminal Law: Statutes. Penal statutes are to be strictly construed in
    favor of the defendant.
    26. Sentences: Evidence: Presentence Reports. Even if the State presents
    evidence in favor of a specific sentence and the defendant declines to
    present contrary evidence, a court receives and must consider indepen-
    dent information from a presentence investigation report.
    27. Sentences: Death Penalty: Evidence: Presentence Reports. In a death
    penalty case, a sentencing panel is required to review a presentence
    investigation report and determine whether it contradicts the State’s evi-
    dence of aggravating factors and whether any mitigating circumstances
    exist, including specifically delineated statutory mitigators.
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    28. Death Penalty: Aggravating and Mitigating Circumstances: Proof.
    While the State must prove aggravating circumstances beyond a rea-
    sonable doubt in a death penalty case, there is no burden of proof with
    regard to mitigating circumstances.
    29. Sentences: Death Penalty: Aggravating and Mitigating Circum­
    stances: Judgments. Once a sentencing panel in a death penalty case
    makes its determinations about the existence of aggravating and mitigat-
    ing circumstances, the panel is then required to undertake a proportion-
    ality review.
    30. Criminal Law: Sentences: Death Penalty: Words and Phrases. A pro-
    portionality review in a death penalty case looks at whether the sentence
    of death is excessive or disproportionate to the penalty imposed in simi-
    lar cases, considering both the crime and the defendant. Proportionality
    review is not constitutionally mandated.
    31. Sentences: Death Penalty: Statutes: Appeal and Error. The propor-
    tionality review in a death penalty case exists in Nebraska by virtue of
    statutes which direct the Nebraska Supreme Court to conduct a propor-
    tionality review in each appeal in which a death sentence is imposed.
    32. Sentences: Death Penalty. A court’s proportionality review spans all
    previous cases in which a sentence of death is imposed and is not depen-
    dent on which cases are put forward by the parties.
    33. Sentences: Death Penalty: Aggravating and Mitigating Circum­
    stances: Judgments: Juries. Even when a jury determines the existence
    of an aggravating circumstance, a sentencing panel is required to put in
    writing its consideration of whether the determined aggravating circum-
    stance justifies the imposition of a sentence of death, whether mitigating
    circumstances exist, and whether a sentence of death would be excessive
    or disproportionate to penalties imposed in similar cases.
    34. ____: ____: ____: ____: ____. A sentencing panel’s order imposing
    a sentence of death where a jury has determined the existence of an
    aggravating circumstance must specifically refer to the aggravating and
    mitigating circumstances weighed in the determination of the panel.
    35. Sentences: Death Penalty: Statutes. Nebraska’s capital sentencing
    scheme provides additional statutory steps and considerations to ensure
    fairness and accuracy, and these safeguards exist regardless of a defend­
    ant’s strategy at the penalty phase.
    36. Sentences: Death Penalty. Due to Nebraska’s statutory capital sentenc-
    ing scheme, a defendant cannot “choose” the death penalty.
    37. Courts: Sentences: Death Penalty. A sentencing decision in a death
    penalty case rests with the court alone.
    38. Sentences: Death Penalty: Aggravating and Mitigating Circum­
    stances: Evidence: Presentence Reports. In order to sentence a
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    STATE v. SCHROEDER
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    defendant to death, the statutory scheme requires that a sentencing
    panel consider not only evidence and argument presented by the parties
    but also an independently compiled presentence investigation report to
    determine whether the alleged aggravating circumstance exists, deter-
    mine whether any mitigating factors are present which would weigh
    against the imposition of the death penalty, and conduct a proportional-
    ity review weighing the aggravating and mitigating factors and compar-
    ing the facts to previous cases where the death penalty was imposed.
    39.   Trial: Parties. A defendant is entitled to present a defense and is guar-
    anteed the right to choose the objectives for that defense.
    40.   Attorney and Client. A self-represented defendant must be allowed to
    control the organization and content of his own defense.
    41.   Constitutional Law: Right to Counsel: Sentences: Aggravating
    and Mitigating Circumstances: Evidence: Waiver. When a defend­
    ant waives counsel and the presentation of mitigating evidence, the
    appointment of an advocate to present evidence and argue against the
    imposition of a sentence overrides that defendant’s constitutional right
    to control the organization and content of his or her own defense dur-
    ing sentencing.
    42.   Right to Counsel: Waiver. A criminal defendant has the right to waive
    counsel and present his or her own defense.
    43.   Sentences: Death Penalty: Right to Counsel: Evidence: Waiver. In a
    death penalty case, a defendant’s right to waive counsel and present his
    or her own defense includes the right of the defendant to elect not to
    present additional evidence or argument during the penalty proceedings.
    44.   Sentences: Death Penalty: Aggravating and Mitigating Circum­
    stances: Appeal and Error. In reviewing a sentence of death, the
    Nebraska Supreme Court conducts a de novo review of the record to
    determine whether the aggravating and mitigating circumstances support
    the imposition of the death penalty.
    45.   ____: ____: ____: ____. In reviewing a sentence of death, the Nebraska
    Supreme Court considers whether the aggravating circumstances justify
    imposition of a sentence of death and whether any mitigating circum-
    stances found to exist approach or exceed the weight given to the aggra-
    vating circumstances.
    46.   ____: ____: ____: ____. The Nebraska Supreme Court is required, upon
    appeal, to determine the propriety of a death sentence by conducting a
    proportionality review, comparing the aggravating and mitigating cir-
    cumstances with those present in other cases in which a court imposed
    the death penalty.
    47.   Sentences: Death Penalty. The purpose of a proportionality review in a
    death penalty case is to ensure that the sentences imposed in a case are
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    STATE v. SCHROEDER
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    no greater than those imposed in other cases with the same or similar
    circumstances.
    48.   Sentences: Death Penalty: Aggravating and Mitigating Circum­
    stances: Appeal and Error. The Nebraska Supreme Court’s propor-
    tionality review looks only to other cases in which the death penalty
    has been imposed and requires the court to compare the aggravating
    and mitigating circumstances of the case on appeal with those present in
    those other cases.
    49.   Death Penalty. A proportionality review in a death penalty case does
    not require that a court “color match” cases precisely.
    50.   Sentences: Death Penalty. The question when conducting a propor-
    tionality review in a death penalty case is simply whether the cases
    being compared are sufficiently similar, considering both the crime and
    the defendant, to provide the court with a useful frame of reference for
    evaluating the sentence in the instant case.
    51.   Sentences: Death Penalty: Aggravating and Mitigating Circum­
    stances. One aggravating circumstance may be sufficient under
    Nebraska’s statutory system for the imposition of the death penalty.
    52.   ____: ____: ____. In a proportionality review, the evaluation of whether
    the death penalty should be imposed in a specific case is not a mere
    counting process of “X” number of aggravating circumstances and
    “Y” number of mitigating circumstances and, instead, asks whether the
    reviewed cases are sufficiently similar to provide a useful reference for
    that evaluation.
    Appeal from the District Court for Johnson County: Vicky
    L. Johnson, Judge. Affirmed.
    Sarah P. Newell, of Nebraska Commission on Public
    Advocacy, for appellant.
    Douglas J. Peterson, Attorney General, and James D. Smith,
    Solicitor General, for appellee.
    Christopher L. Eickholt, of Eickholt Law, L.L.C., Cassandra
    Stubbs, of American Civil Liberties Union Foundation, and
    Amy A. Miller, of ACLU of Nebraska Foundation, for amicus
    curiae ACLU and ACLU of Nebraska.
    Heavican, C.J., Miller-Lerman, Cassel, Stacy, Funke,
    and Papik, JJ., and Moore, Chief Judge.
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    STATE v. SCHROEDER
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    Funke, J.
    Patrick W. Schroeder appeals his sentence of death for
    first degree murder of Terry Berry, Jr. This is a mandatory
    direct appeal pursuant to Neb. Rev. Stat. § 29-2525 (Cum.
    Supp. 2018) and article I, § 23, of the Nebraska Constitution.
    Schroeder waived counsel, pled guilty without a plea agree-
    ment, waived the right to a jury on the issue of aggravating
    factors, declined to present evidence of aggravating or mitigat-
    ing factors, and declined to cooperate for the preparation of the
    presentence investigation report.
    On appeal, Schroeder was appointed counsel and now con-
    tends that the sentencing panel erred in allowing the State to
    introduce evidence to refute unpresented mitigating evidence,
    failing to consider and weigh mitigating evidence from the
    presentence investigation report, failing to request documenta-
    tion from the Department of Correctional Services (DCS) of
    Schroeder’s time in custody for mitigation purposes, sentenc-
    ing Schroeder to death with insufficient safeguards to prevent
    arbitrary results, and finding Schroeder should be sentenced to
    death after balancing the aggravating evidence and mitigating
    evidence. For the reasons set forth herein, we affirm.
    BACKGROUND
    Factual Background
    At the time of the events leading to Schroeder’s instant
    conviction, Schroeder was incarcerated at Tecumseh State
    Correctional Institution (TSCI). This incarceration was pur-
    suant to a 2007 conviction for the first degree murder of
    Kenneth Albers in which Schroeder was sentenced to life
    imprisonment.
    In March 2017, while housed in a cell intended for one
    occupant, Schroeder was asked if he would consider a room-
    mate due to overcrowding. Schroeder agreed but wanted a
    roommate with whom he was compatible. Prison officials
    assigned Berry to Schroeder’s cell. Schroeder did not consider
    Berry to be compatible with him and told prison officials that
    he did not want Berry as a cellmate. Schroeder did not know
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    STATE v. SCHROEDER
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    Berry personally before the assignment but knew of Berry as
    “‘a loudmouth, a punk.’” Berry was 22 years old and convicted
    of second degree forgery and a confined person violation.
    Berry was due for release approximately 2 weeks after his
    assignment to Schroeder’s cell.
    Schroeder had described Berry as a constant talker with
    extremely poor hygiene. During their shared confinement,
    Schroeder would urge Berry to be quieter and clean up after
    himself. Schroeder alleged that he had told prison staff that
    placing Berry with him would be an unworkable, bad arrange-
    ment. Schroeder described that prison staff who came by his
    cell would acknowledge the poor fit and even joke that it was
    surprising Schroeder had not killed Berry yet. By April 13,
    2017, Schroeder decided to himself that “‘[s]omething was
    gonna happen’” if Berry was not moved.
    On April 15, 2017, Berry was watching “UFC” on televi-
    sion in the cell and, as Schroeder explained, Berry “‘would
    not shut up.’” Schroeder instructed Berry to move his chair
    to face the television with his back to Schroeder. Schroeder
    proceeded to put Berry in a chokehold and locked his hands.
    He continued to choke Berry for about 5 minutes until his
    arms got tired and then took a nearby towel, wrapped it around
    Berry’s neck, and continued to choke him for about 5 more
    minutes. At that point, Schroeder let up on the towel, believ-
    ing Berry was dead. Schroeder claimed he then tried to push
    the call button in his cell to alert staff to Berry’s condition.
    Around 30 minutes later, Schroeder alerted a passing guard
    that Berry was on the floor by asking, “‘How do you deal
    with a dead body in a cell?’” The guard believed Schroeder
    was joking until Schroeder picked up and dropped Berry’s
    leg. Schroeder has stated that he summoned the guard not for
    Berry’s benefit, but because he wanted Berry’s body removed
    from the cell.
    Berry was transported to a medical facility. On April 19,
    2017, Berry died, having been declared brain dead. A search
    of the cell revealed a torn “kite,” a form inmates use to com-
    municate with prison staff, dated April 13, 2017, and located in
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    the trash. The discarded kite stated that prison staff had to get
    Berry out of the cell before he got hurt.
    Procedural Background
    Pursuant to these events, Schroeder was charged in April
    2017 with first degree murder and use of a weapon to commit
    a felony. Within an information filed in June, the State submit-
    ted a notice of aggravation alleging Schroeder had been con-
    victed of another murder, been convicted of a crime involving
    the use or threat of violence to the person, or had a substantial
    prior history of serious assaultive or terrorizing criminal activ­
    ity. 1 Schroeder was appointed counsel and entered a plea of
    not guilty.
    A hearing was held following Schroeder’s subsequent
    request to dismiss counsel and represent himself. The court
    granted Schroeder’s motion and discharged his counsel but
    also appointed that same counsel to act in a standby role.
    Representing himself, Schroeder withdrew a pending motion
    to quash and requested leave to withdraw his prior plea of not
    guilty. The court granted Schroeder leave to withdraw his prior
    plea and rearraigned him. Thereafter, Schroeder pled guilty to
    both counts and the court found him guilty of those charges
    beyond a reasonable doubt.
    Presentence Investigation Report
    The court ordered a presentence investigation report.
    Schroeder declined to answer questions or participate in its
    preparation. However, the current report did attach the 2007
    presentence investigation report from Schroeder’s earlier con-
    victions, which supplies more background information.
    According to the report, Schroeder was born in June 1977.
    Schroeder’s biological father abandoned his family when
    Schroeder was an infant. Schroeder’s mother and stepfather
    raised him in his early years. Schroeder described his step­father
    as an alcoholic. Schroeder’s mother and stepfather separated
    1
    See Neb. Rev. Stat. § 29-2523(1)(a) (Cum. Supp. 2018).
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    STATE v. SCHROEDER
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    when Schroeder was 9 years old, and Schroeder moved with
    his mother to Kearney, Nebraska. Schroeder has not had con-
    tact with his stepfather since he was 12 years old. Schroeder
    has two older brothers but, at the time of the 2007 report, was
    not close to either of them. While Schroeder’s biological father
    did take him in for a brief period of time when he was 12 years
    old, Schroeder was removed and sent to a juvenile facility
    because his father caught him smoking marijuana. Schroeder
    denied being abused or neglected and described his childhood
    as “‘typical.’” Schroeder has a history of “placement in foster
    care and group home situations including a number of run-
    aways.” At one point as a teenager, Schroeder was placed with
    his grandparents for a period of time.
    Schroeder was married in 1998 and has one child from that
    marriage, but the couple has since divorced. At the time of the
    2007 report, Schroeder described that the child was adopted
    by his ex-wife’s present husband and that Schroeder has no
    contact with the child. Schroeder remarried in 2003, and his
    wife had three children from prior relationships. However,
    Schroeder said in the 2007 report that while the couple was
    then together, he expected the situation to change under the
    circumstances.
    The presentence investigation report provides that Schroeder
    has an eighth grade education. Before he was incarcerated in
    2007, he had been employed in various farmwork and con-
    struction jobs.
    Schroeder reported that he first used alcohol when he was 13
    years old and that he experimented with marijuana and cocaine
    when he was 15 years old. Schroeder also admitted he had
    used methamphetamine on a daily basis for approximately 3 to
    4 months, with the last use in 2003. While Schroeder denied
    receiving treatment, previous prison records indicated he was
    placed in substance abuse programming in 1991. Schroeder
    asserted that from April 2005 until his 2006 arrest, he was
    “‘hooked on opiates’” and was taking between 500 and 800
    pills per month, some of which were prescribed and some of
    which were not.
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    The report explained that in 1985, Schroeder was first
    charged with criminal mischief in juvenile court when he was
    12 years old. Between 1987 and 1992, Schroeder was also
    charged in juvenile court with aiding and abetting, escape,
    theft, minor in possession of alcohol, and theft by exercis-
    ing control. He was ordered to serve probation as well as
    being placed in the Youth Rehabilitation and Treatment Center
    in Kearney.
    Since reaching the age of majority, in addition to his 2007
    convictions, Schroeder has been convicted of bank robbery,
    forgery, escape, theft, assault, driving under suspension, con-
    tributing to the delinquency of a child, driving under the
    influence, and issuing bad checks. He has been sentenced to
    multiple terms of incarceration and terms of supervision. He
    has had two of his terms of probation revoked and completed
    others unsatisfactorily.
    Sentencing Proceedings
    A scheduling hearing was held in August 2017. Schroeder
    waived his right to a jury for a determination of the aggrava-
    tion allegation. The court accepted this waiver after making
    inquiry and finding, beyond a reasonable doubt, that Schroeder
    was competent and that his decision was made freely, volun-
    tarily, knowingly, and intelligently. Thereafter, a three-judge
    panel was convened for a sentencing hearing on Schroeder’s
    first degree murder conviction.
    On the aggravation allegation, the State presented evidence
    of Schroeder’s 2007 conviction for Albers’ murder. A ser-
    geant with the Nebraska State Patrol testified that he was
    the lead investigator for that case. His testimony and a video
    of his interview with Schroeder described that Albers was a
    75-year-old farmer who had previously employed Schroeder.
    Believing Albers had several thousand dollars in cash at his
    residence, Schroeder had driven to Albers’ house, rung the
    doorbell, entered the home, and awakened Albers. Schroeder
    demanded money, threatened Albers, and hit him in the head
    with a nightstick. Albers recognized Schroeder during this
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    exchange and called him by name. Schroeder forced Albers
    to open a lockbox in which Schroeder believed the cash was
    kept, after which Schroeder took Albers outside to an adjacent
    shop. At the shop, Albers turned toward Schroeder, attempting
    to defend himself. Schroeder struck Albers with the nightstick
    four or five times. With Albers on the floor, Schroeder dragged
    him out of the shop, tied him up with battery cables, and
    placed him in the back of Albers’ pickup. Schroeder then drove
    Albers, who was still alive, to an abandoned well on the prop-
    erty and dumped him into it. Schroeder explained to the ser-
    geant that he had made the decision to kill Albers a few days
    before the robbery. The doctor who performed the autopsy on
    Albers testified that the cause of Albers’ death was blunt force
    trauma to his head.
    Schroeder declined to cross-examine the State’s witnesses,
    present rebuttal evidence, or argue against the State’s claim on
    the aggravation allegation.
    As to mitigating factors, Schroeder again declined to pre­
    sent any evidence or argument. However, the State requested,
    and the court granted, permission to present evidence to negate
    possible statutory mitigating circumstances. Here, the State
    presented evidence related to Berry’s murder. Investigator
    Stacie Lundgren of the Nebraska State Patrol testified to her
    interview with Schroeder where he described how and why
    he killed Berry. This interview was also described in the pre-
    sentence investigation report. The doctor who performed the
    autopsy of Berry opined that the cause of death was compres-
    sional asphyxia, a form of strangulation where the structures
    of the neck are compressed. Cpl. Steve Wilder explained that
    he was the correctional officer whom Schroeder flagged down
    to remove Berry after Schroeder had choked him. Cpl. Joseph
    Eppens testified he had moved Schroeder from his cell follow-
    ing the incident. Eppens explained that Schroeder told him he
    had previously informed correctional staff he did not want a
    cellmate and that he joked, “[T]his is what happens when we
    watch UFC.” Finally, a TSCI employee testified that he had
    notarized a writing in which Schroeder stated:
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    My name is Patrick Schroeder. I’m 40 years old and
    I killed Terry Berry on April 15[,] 2017[.] I killed Berry
    because I wanted to, I knew I was going to kill him the
    moment staff put him in my cell on April 10[,] 2017. . . .
    I’m writing this statement to inform the court that if
    given another life term I will kill again and we will be
    right back in court doing this all over again.
    The court allowed the parties to make arguments. Schroeder
    declined. On the aggravation allegation, the State noted that
    it provided a certified copy of Schroeder’s previous murder
    conviction and testimony concerning the events leading to that
    conviction. As to mitigating circumstances, the State stated,
    in part:
    [T]he State has offered evidence considering the statutory
    mitigating circumstances, and the purpose of the evidence
    was to affirmatively show that there were no statutory
    mitigators that exist in this case.
    The circumstances to be considered for mitigation
    include whether or not the defendant acted under unusual
    pressure or influence. I want to emphasize the word
    “unusual.” His justification[s] for his actions are more of
    a nuisance than they are unusual pressure.
    It was displeasure or disagreement with a roommate
    and how the roommate either talked too much or his
    hygiene wasn’t appropriate for . . . Schroeder’s standards,
    and I don’t think that constitutes unusual pressure or
    influence.
    He’s not under the . . . dominion of another. . . .
    Schroeder acted by himself, and I would say he probably
    was the boss in the cell.
    There is no undue influence of extreme mental or emo-
    tional disturbance. . . . Schroeder was clear thinking, and
    by the evidence that’s been presented, his thought process
    started almost immediately upon . . . Berry becoming
    his cellmate. And in his written statement, that is really
    clear. And even in his interview with the investigator, he
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    started thinking about this several days before it actu-
    ally happened.
    So he wasn’t under any influence of extreme mental or
    emotional disturbance. This was a thought process delib-
    erate and pretty cold blooded.
    ....
    The evidence shows that he was the sole person com-
    mitting this crime. There is no accomplice. And his par-
    ticipation is the . . . death-causing participation.
    The State would argue that . . . Berry’s habits as
    described by [Schroeder do] not make him a participant
    [in the incident].
    ....
    [Schroeder] was a prisoner at the institution. No evi-
    dence of impairment. The only evidence is that he’s clear-
    headed, he’s thinking, and he planned.
    Order of Sentence
    In the panel’s order of sentence, the panel found the State
    proved the aggravation allegation beyond a reasonable doubt,
    citing Schroeder’s previous conviction and the testimony
    describing the events leading to that conviction.
    The panel also addressed possible statutory mitigating cir-
    cumstances, noting, “The State was allowed to present evi-
    dence that is probative of the non-existence of statutory or non-
    statutory mitigating circumstances, and did so[, and Schroeder]
    was allowed to present evidence that is probative of the exis-
    tence of a statutory or non-statutory mitigating circumstance[,
    but] chose not to . . . .” After analyzing each of the mitigating
    grounds defined by § 29-2523(2) and giving Schroeder the
    benefit of all inferences, the panel did not find there were any
    statutory mitigating circumstances.
    The panel addressed various nonstatutory mitigating factors.
    The panel found two of these factors existed and weighed in
    Schroeder’s favor, including that Schroeder’s guilty plea spared
    Berry’s family the trauma of a trial and the State the expense of
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    a trial and that Schroeder’s childhood and family were dysfunc-
    tional. While finding three other factors did not exist, the panel
    noted the following: Schroeder is not well educated, but there
    is no evidence of a borderline intellect or diminished cogni-
    tive ability and he clearly knows right from wrong; Schroeder
    takes medication for depression, but there is nothing to suggest
    that this depression contributed to his actions and there is no
    evidence that his psychiatric or psychological history rises to
    the level of a mitigating circumstance; and the record does not
    suggest Schroeder has generally been a problem to officials
    during his confinement, but this prior conduct does not rise to
    the level of a mitigating factor. The panel acknowledged that
    Schroeder apparently “expressly welcomes a death sentence”
    but explained this was not considered and that “[i]t is the law,
    and not [Schroeder’s] wishes, that compels this Panel’s ulti-
    mate conclusion.”
    The panel concluded that the two nonstatutory mitigating
    circumstances were given little weight because these two fac-
    tors did not approach or exceed the weight given to the aggra-
    vating circumstance. The panel then conducted a proportional-
    ity review and found that a sentence of death is not excessive
    or disproportionate to the penalty imposed in similar cases.
    Based upon all of the above, the panel sentenced Schroeder
    to death.
    ASSIGNMENTS OF ERROR
    Schroeder assigns, restated, that the sentencing court erred
    in (1) allowing the State to introduce evidence to rebut unpre-
    sented mitigating evidence, (2) failing to consider and prop-
    erly weigh mitigating evidence from the presentence inves-
    tigation report, (3) failing to request DCS documentation of
    Schroeder’s time in custody for mitigation purposes, (4) sen-
    tencing Schroeder to death with insufficient safeguards to
    prevent arbitrary results, and (5) sentencing Schroeder to death
    after balancing the aggravating evidence and mitigating evi-
    dence and conducting the proportionality review.
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    STANDARD OF REVIEW
    [1] In a capital sentencing proceeding, this court conducts an
    independent review of the record to determine if the evidence
    is sufficient to support imposition of the death penalty. 2
    [2-4] When reviewing the sufficiency of the evidence to
    sustain the trier of fact’s finding of an aggravating circum-
    stance, the relevant question for this court is whether, after
    viewing the evidence in the light most favorable to the State,
    any rational trier of fact could have found the essential ele-
    ments of the aggravating circumstance beyond a reasonable
    doubt. 3 The sentencing panel’s determination of the existence
    or nonexistence of a mitigating circumstance is subject to de
    novo review by this court. 4 In reviewing a sentence of death,
    the Nebraska Supreme Court conducts a de novo review of the
    record to determine whether the aggravating and mitigating
    circumstances support the imposition of the death penalty. 5
    [5] In proceedings where the Nebraska Evidence Rules
    apply, the admissibility of evidence is controlled by the
    Nebraska Evidence Rules; judicial discretion is involved
    only when the rules make discretion a factor in determining
    admissibility. 6
    [6] The constitutionality of a statute presents a question of
    law, which an appellate court independently reviews. 7
    ANALYSIS
    Rebuttal of Mitigating
    Circumstances
    [7] Under Nebraska law, the death penalty is imposed
    for a conviction of murder in the first degree only in those
    2
    State v. Jenkins, 
    303 Neb. 676
    , 
    931 N.W.2d 851
    (2019).
    3
    State v. Torres, 
    283 Neb. 142
    , 
    812 N.W.2d 213
    (2012).
    4
    Jenkins, supra note 2.
    5
    Id. 6 Torres,
    supra note 3.
    7
    Jenkins, supra note 2.
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    instances when the aggravating circumstances existing in
    connection with the crime outweigh the mitigating circum­
    stances. 8 When, as here, a defendant waives the right to a
    jury determination of alleged aggravating circumstances, the
    proc­ess for a sentencing panel to consider, find, and weigh the
    applicable aggravating and mitigating circumstances is set out
    by Neb. Rev. Stat. § 29-2521(2) (Cum. Supp. 2018). Section
    29-2521(2) states:
    In the sentencing determination proceeding before a panel
    of judges when the right to a jury determination of the
    alleged aggravating circumstances has been waived, the
    panel shall . . . hold a hearing. At such hearing, evidence
    may be presented as to any matter that the presiding judge
    deems relevant to sentence and shall include matters
    relating to the aggravating circumstances alleged in the
    information, to any of the mitigating circumstances set
    forth in section 29-2523, and to sentence excessiveness
    or disproportionality. The Nebraska Evidence Rules shall
    apply to evidence relating to aggravating circumstances.
    Each aggravating circumstance shall be proved beyond a
    reasonable doubt. Any evidence at the sentencing deter-
    mination proceeding which the presiding judge deems to
    have probative value may be received. The state and the
    defendant or his or her counsel shall be permitted to pre­
    sent argument for or against sentence of death.
    The mitigating circumstances required to be considered
    under § 29-2521 and set forth in § 29-2523(2) include:
    (a) The offender has no significant history of prior
    criminal activity;
    (b) The offender acted under unusual pressures or
    influences or under the domination of another person;
    (c) The crime was committed while the offender was
    under the influence of extreme mental or emotional
    disturbance;
    (d) The age of the defendant at the time of the crime;
    8
    Neb. Rev. Stat. § 29-2519 (Cum. Supp. 2018).
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    (e) The offender was an accomplice in the crime com-
    mitted by another person and his or her participation was
    relatively minor;
    (f) The victim was a participant in the defendant’s con-
    duct or consented to the act; or
    (g) At the time of the crime, the capacity of the defend­
    ant to appreciate the wrongfulness of his or her conduct
    or to conform his or her conduct to the requirements of
    law was impaired as a result of mental illness, mental
    defect, or intoxication.
    [8] Schroeder initially claims that the sentencing panel erred
    by allowing the State to present evidence to rebut the statutory
    mitigating circumstances even though Schroeder did not offer
    any evidence on mitigation. In making this claim, Schroeder
    cites the proposition that rebuttal evidence is confined to new
    matters first introduced by the opposing party and limited to
    that which explains, disproves, or counteracts the opposing
    party’s evidence. 9
    [9-11] Contrary to Schroeder’s assertions under this assign-
    ment, a sentencing panel has the discretion to hear evidence
    to address potential mitigating circumstances regardless of
    whether the defendant presents evidence on that issue. As
    quoted above, § 29-2521(2) allows a sentencing panel to
    receive “[a]ny evidence” at the sentencing proceeding which
    the presiding judge deems to have probative value relevant
    to the sentence including to any of the statutory mitigating
    circumstances. 10 A sentencing court has broad discretion as to
    the source and type of evidence and information which may
    be used in determining the kind and extent of the punishment
    to be imposed, and evidence may be presented as to any mat-
    ter that the court deems relevant to the sentence. 11 Although
    § 29-2521(2) dictates that the Nebraska Rules of Evidence
    9
    See State v. Sandoval, 
    280 Neb. 309
    , 
    788 N.W.2d 172
    (2010). See, also,
    State v. Molina, 
    271 Neb. 488
    , 
    713 N.W.2d 412
    (2006).
    10
    See Jenkins, supra note 2.
    11
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    apply when determining the aggravating circumstances alleged
    by the information, it contains no such requirement for con-
    sideration of mitigating circumstances. Because a sentencing
    panel is required to consider and weigh any mitigating cir-
    cumstances in imposing a sentence of death, the introduction
    of evidence of the existence or nonexistence of these potential
    mitigators has probative value to the sentence. Thus, the panel
    could permit the State to present evidence to contradict poten-
    tial mitigators even though Schroder failed to present affirma-
    tive evidence.
    Schroeder argues the State’s evidence purported to rebut
    the statutory mitigating circumstances was actually offered
    to support uncharged aggravating circumstances. Specifically,
    Schroeder alleges the State’s evidence was offered to show the
    nonstatutory aggravating circumstance of future dangerous-
    ness and “both prongs” 12 of § 29-2523(1)(d), which provides
    a statutory aggravator when a murder was especially heinous,
    atrocious, or cruel or manifested exceptional depravity by ordi-
    nary standards of morality and intelligence.
    During the portion of the hearing devoted to mitigating
    circumstances, the State’s evidence related to Berry’s murder.
    Lundgren testified about her interview with Schroeder where
    he described how and why he killed Berry. This same interview
    was also described in the presentence investigation report. The
    doctor who performed the autopsy on Berry explained that
    Berry was killed by strangulation. Wilder explained the events
    surrounding his discovery of Berry’s murder and Schroeder’s
    reaction. Eppens explained that Schroeder told him he had pre-
    viously informed correctional staff he did not want a cellmate
    and joked, while Eppens was moving him following the dis-
    covery of Berry’s unconscious body, “[T]his is what happens
    when we watch UFC.” Additionally, through the testimony of
    a TSCI employee, the State introduced a notarized writing in
    which Schroeder confessed, explained his reasons for killing
    Berry, and stated he would kill again if given another life term.
    12
    Brief for appellant at 28.
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    This evidence surrounding Berry’s murder was relevant
    to the statutory mitigating circumstances the panel was
    required to consider. The mitigating circumstances listed under
    § 29-2523(2) involve, in part, circumstances surrounding the
    underlying crime. These circumstances include pressure or
    influences which may have weighed on the defendant, poten-
    tial influence on the defendant of extreme mental or emotional
    disturbance at the time of the offense, potential victim partici-
    pation or consent to the act, the defendant’s capacity to appre-
    ciate the wrongfulness of the act at the time of the offense,
    and any mental illness, defect, or intoxication which may have
    contributed to the offense. 13 The State’s evidence informed
    the panel’s analysis and was relevant to consideration of these
    mitigators; and, as explained above, the panel had discretion to
    hear this evidence.
    Schroeder fails to allege that the introduction of this evi-
    dence influenced the panel’s finding of the existence of the
    charged aggravator—namely that Schroeder had been convicted
    of another murder, been convicted of a crime involving the use
    or threat of violence to the person, or had a substantial prior
    history of serious assaultive or terrorizing criminal activity. 14 It
    is undisputed that Schroeder had previously been convicted of
    the murder of Albers and was incarcerated for that crime at the
    time of Berry’s killing. Schroeder does not challenge the pre-
    sentation of evidence related to this aggravating circumstance
    for failing to comply with the Nebraska Evidence Rules. 15
    The panel had discretion to hear any evidence relevant to
    sentencing, the panel was required to consider mitigating cir-
    cumstances even though Schroeder failed to allege or present
    evidence in support of them, and the evidence presented by the
    State was relevant to the panel’s review of these mitigators.
    As such, the panel did not err in allowing the State to present
    evidence on the existence of mitigating circumstances.
    13
    § 29-2523(2).
    14
    § 29-2523(1)(a).
    15
    See § 29-2521(2).
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    Weighing of Mitigating
    Circumstances
    Schroeder next assigns the panel failed to properly con-
    sider mitigating information contained within the presentence
    investigation report and available from the State’s evidence.
    Schroeder claims proper consideration of this evidence would
    have led the panel to find additional statutory and nonstatutory
    mitigating circumstances.
    [12] As explained, § 29-2521 requires a sentencing panel to
    consider mitigating circumstances. Neb. Rev. Stat. § 29-2522
    (Cum. Supp. 2018) describes the weighing of the aggravat-
    ing and mitigating circumstances in imposing a sentence of
    death and requires that the determination be in writing and
    refer to the aggravating and mitigating circumstances weighed.
    Accordingly, the sentencing order must specify the factors it
    relied upon in reaching its decision and focus on the individual
    circumstances of each homicide and each defendant. 16
    We first address Schroeder’s claims that the panel should
    have applied additional nonstatutory mitigating evidence,
    including (1) that the State had ulterior motives for pursu-
    ing the death penalty to avoid and detract from potential civil
    liability for failing to protect Berry, (2) that Schroeder was
    institutionalized from consistent incarceration, and (3) that
    Schroeder had used money elicited from his murder of Albers
    to provide clothes and food for his family.
    [13,14] The U.S. Constitution does not require the sen-
    tencing judge or judges to make specific written findings
    with regard to nonstatutory mitigating factors. 17 In State v.
    Jenkins, 18 we addressed an assignment of a sentencing panel
    failing to address nonstatutory mitigators and explained that
    16
    State v. Dunster, 
    262 Neb. 329
    , 
    631 N.W.2d 879
    (2001).
    17
    State v. Bjorklund, 
    258 Neb. 432
    , 
    604 N.W.2d 169
    (2000), abrogated
    on other grounds, State v. Mata, 
    275 Neb. 1
    , 
    745 N.W.2d 229
    (2008).
    Accord State v. Reeves, 
    234 Neb. 711
    , 
    453 N.W.2d 359
    , cert. granted and
    judgment vacated 
    498 U.S. 964
    , 
    111 S. Ct. 425
    , 
    112 L. Ed. 2d 409
    (1990).
    18
    Jenkins, supra note 2.
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    we will not fault the panel for failing to discuss a nonstatu-
    tory mitigating circumstance that it was not specifically asked
    to consider.
    Additionally, the underlying facts Schroeder uses as sup-
    port for these nonstatutory mitigators are included in the
    presentence investigation report which the panel explained it
    considered in determining his sentence. The panel also specifi-
    cally acknowledged many of these facts in its sentencing order.
    On the allegation that the State had ulterior motives due to
    potential liability, the panel explained the cell Schroeder and
    Berry shared was intended for a single inmate, Berry was set
    for release 2 weeks after moving in with Schroeder, Schroeder
    was serving a life sentence for Albers’ murder, and Schroeder
    warned that issues might arise if he were incompatible with
    whoever was assigned as his roommate. As to institutional-
    ization, the panel described Schroeder’s current incarceration
    for Albers’ murder and noted his dysfunctional childhood and
    that “[h]e was involved in the juvenile court at a young age.”
    Finally, on the use of money he attained from Albers’ murder,
    the panel described that he took several thousand dollars from
    Albers after leaving him for dead and “drove around the area,
    paying off bills and making purchases.” It is clear the panel
    considered and weighed these facts even though it did not state
    a finding that they led to the specific nonstatutory mitigating
    circumstances Schroeder presently claims.
    Because the panel was not required to make specific writ-
    ten findings on the application of nonstatutory mitigating fac-
    tors, and taking into account the panel’s consideration of
    the facts Schroeder alleges support these factors, Schroeder’s
    claims involving the nonstatutory mitigators do not demon-
    strate reversible error.
    We next turn to Schroeder’s claim that the panel failed
    in its analysis of statutory mitigating circumstances. Of the
    statutory mitigating factors, Schroeder claims the panel should
    have determined the following applied: Schroeder acted under
    unusual pressures or influences or under the domination
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    of another person, 19 Berry’s murder was committed while
    Schroeder was under the influence of extreme mental or emo-
    tional disturbance, 20 and Berry was a participant in Schroeder’s
    conduct or consented to the act. 21
    For Schroeder’s claims that he was under unusual pressures
    or influences and extreme mental or emotional disturbance,
    he first alleges the panel failed to acknowledge his efforts to
    get Berry removed as a cellmate and his incompatibility with
    Berry. He supports this allegation by referencing the panel’s
    determination that Schroeder had calculated Berry’s murder for
    several days and chose no method of obviating his annoyance.
    Schroeder further quoted the panel’s explanation that finding
    the kite in the trash “suggests a premeditative and depraved
    mentality” in that Schroeder “did not ask that [Berry] be
    moved” and in that Schroeder “did not tell the guards that . . .
    Berry was in mortal danger if he were not moved.”
    Schroeder contends this determination and the findings
    supporting it are contradicted by the evidence. Specifically,
    Schroeder points to the summaries of his interviews with
    Lundgren, included in the presentence investigation report,
    wherein he told Lundgren that he had “‘told all of the staff’”
    that he did not want Berry as a cellmate, that he told staff
    members he was not compatible with Berry when they assigned
    him to Schroeder’s cell, that a TSCI caseworker had tried to
    get the assignment switched prior to Berry’s moving in, and
    that corrections officers would laugh at the arrangement and
    joke they were surprised Schroeder had not killed Berry yet.
    Schroeder also points to Lundgren’s case synopsis noting that
    the TSCI caseworker Schroeder described in his interview
    explained that she did have concerns prior to Berry’s moving
    into the cell based on a “‘gut feeling’” that the arrangement
    would be “‘a bad idea’” but that she was unsuccessful in get-
    ting it switched.
    19
    See § 29-2523(2)(b).
    20
    See § 29-2523(2)(c).
    21
    See § 29-2523(2)(f).
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    However, the panel’s statements that Schroeder did not ask
    for Berry to be moved and did not warn that Berry was in
    mortal danger are not contradicted by Lundgren’s summaries.
    Lundgren’s summary of Schroeder’s interview only described
    Schroeder’s assertions that he told staff prior to Berry’s mov-
    ing in that he did not want Berry as a cellmate and was
    incompatible with him. Lundgren’s summary did not describe
    that Schroeder asserted he continued these complaints after
    the move was made and did not allege he made any actual
    requests for Berry to be moved. Moreover, there is nothing in
    Schroeder’s description of his interactions with TSCI officials
    where he indicated Berry was in mortal danger if they con-
    tinued to share the cell. While Schroeder alleged corrections
    officers would joke they were surprised he had not killed Berry
    yet, such statements do not imply that Schroeder requested that
    Berry be moved or that they believed or had reason to believe
    that Berry was actually in mortal danger. Similarly, while
    the TSCI caseworker attempted to get Berry’s assignment to
    Schroeder’s cell switched prior to his move, there is nothing
    indicating that she was doing so at Schroeder’s request or that
    her “‘gut feeling’” was based upon a belief such an arrange-
    ment might lead to Berry’s death.
    The panel reviewed the presentence investigation report and
    Lundgren’s summaries prior to determining whether there were
    mitigating circumstances. The panel’s findings that Schroeder
    did not request Berry’s removal from his cell and did not warn
    officials of potential danger to Berry is uncontradicted by the
    report. Instead, the report shows that Schroeder acted with
    premeditation and depravity in that Schroeder explained he had
    made up his mind to kill Berry days before he did so and in
    that he made no real attempts to avoid this result, even having
    made the decision to discard the kite which could have helped
    avoid the killing.
    Schroeder’s explanations in his interview that he killed
    Berry because he was unclean and annoying do not rise to the
    level of accounts of unusual pressure or influence or extreme
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    mental or emotional disturbance. Nothing in the record indi-
    cates that Schroeder continually sought Berry’s removal
    from the cell or that any such requests were unheeded by
    TSCI staff.
    Schroeder references the effect incarceration can have on
    inmates in support of his unusual pressures or influences and
    extreme mental or emotional disturbance claims. Schroeder
    cites to several articles, while acknowledging he did not pro-
    vide them to the court because he did not present any evidence,
    which discuss the effects of institutionalization and incarcera-
    tion in solitary confinement on an inmate’s mental health as
    well as articles and reports of security and staffing issues at
    TSCI and DCS.
    [15] We have previously addressed the effect incarceration
    and, specifically, isolated confinement can have on individu-
    als. In Jenkins, we analyzed the application of a nonstatutory
    mitigating factor of solitary confinement and quoted the under-
    standing that “‘[y]ears on end of near-total isolation exact a
    terrible price.’” 22 However, we also noted that prison officials
    must have discretion to decide that in some instances, tem-
    porary solitary confinement is a useful or necessary means to
    impose discipline and to protect prison employees and other
    inmates. 23 Because of the defendant’s own extensive and vio-
    lent actions in that case, the prison officials needed to have
    some recourse to deal with such an inmate, and we found that
    it was reasonable in not rewarding such behavior by consider-
    ing the resulting confinement as a mitigating factor. 24 For the
    same reasons, the mere identification of a history of incar-
    ceration, without more, is insufficient to allege unusual pres-
    sures or influences or establish extreme mental or emotional
    22
    Jenkins, supra note 
    2, 303 Neb. at 727
    , 931 N.W.2d at 888, quoting
    Davis v. Ayala, 
    576 U.S. 257
    , 
    135 S. Ct. 2187
    , 
    192 L. Ed. 2d 323
    (2015)
    (Kennedy, J., concurring).
    23
    Jenkins, supra note 2.
    24
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    disturb­ance. Schroeder’s incarceration was due to his own
    actions, including, most recently, his murder of Albers.
    Contrary to Schroeder’s assertions and as discussed in our
    analysis of Schroeder’s claims of the nonstatutory mitigat-
    ing factors of institutionalization and the State’s alleged ulte-
    rior motive to avoid possible litigation, the underlying facts
    of Schroeder’s claims were acknowledged and weighed by
    the court. In its order, the panel acknowledged that the cell
    Schroeder and Berry shared was intended for a single inmate,
    Berry was set for release 2 weeks after moving in with
    Schroeder, Schroeder was serving a life sentence for Albers’
    murder, and Schroeder had a history of incarceration includ-
    ing his history within the juvenile court system and his current
    sentence for Albers’ murder. The panel reasonably found that
    on their own, these facts and the reality of the effect incarcera-
    tion can have on individuals were insufficient to establish that
    Schroeder acted under unusual pressures or influences or was
    under extreme mental or emotional disturbance. Under our de
    novo review, we reach the same conclusion.
    Schroeder’s remaining claim, that the panel erred in fail-
    ing to find Berry was a participant in Schroeder’s conduct
    or consented to the act, is without merit. Schroeder supports
    this proposition by noting, “Berry complied with Schroeder’s
    request that he turn the chair around and face away from
    Schroeder after Schroeder expressed extreme annoyance with
    his behavior.” 25 However, Berry’s facing away from Schroeder
    does not indicate participation or consent to his murder.
    Schroeder expressed frustration and requested Berry to turn
    away from him. How Berry would have understood this as
    Schroeder’s asking for aid in his strangulation and not as a
    method to avoid conflict is unclear. Schroeder offers no further
    argument to support this mitigating circumstance, and we agree
    with the panel’s finding that there was no evidence establishing
    this mitigating factor.
    25
    Brief for appellant at 40.
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    Duty to Request DCS Chapter 83
    Custody Reports
    Schroeder claims the panel had a duty to request additional
    records of Schroeder’s incarceration from DCS. These records
    are required to be kept by DCS under Neb. Rev. Stat. § 83-178
    (Reissue 2014) and include records concerning Schroeder’s
    background, conduct, associations, and family relationships;
    records regarding Schroeder’s “Central Monitoring,” 26 which
    may be relevant to the propriety of his placement with Berry;
    and any medical or mental health records.
    [16-18] When an offender has been convicted of first degree
    murder and waives the right to a jury determination of an
    alleged aggravating circumstance, the court must order a pre-
    sentence investigation of the offender and the panel must
    consider a written report of such investigation in its sentenc-
    ing determination. 27 The presentence investigation and report
    shall include, when available, any submitted victim statements
    and an analysis of the circumstances attending the commis-
    sion of the crime and the offender’s history of delinquency or
    criminality, physical and mental condition, family situation and
    background, economic status, education, occupation, and per-
    sonal habits. 28 The investigation and report may also include
    any other matters the probation officer deems relevant or the
    court directs to be included. 29
    In this case, the court ordered a presentence investigation
    and report, a report was prepared, and the panel considered it
    during its sentence determination. Schroeder does not allege
    this report failed to analyze and present any of the areas
    required by § 29-2261(3). Instead, Schroeder claims the court
    had a duty to request the presentence investigation report to
    include specific incarceration records. Schroeder relies on State
    26
    Id. at 42.
    27
    § 29-2521(2) and Neb. Rev. Stat. § 29-2261(1) (Reissue 2016).
    28
    § 29-2261(3).
    29
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    v. Dunster 30 for this claim that the panel should have requested
    additional documents.
    In that case, the defendant was sentenced to death after
    pleading guilty to first degree murder. 31 Prior to sentencing,
    the district court instructed the probation officer conducting
    the presentence investigation to include information in the
    possession of DCS as part of the report. 32 The court explained
    that access to this information was restricted by law and that it
    would not be released to the public except upon written order. 33
    On appeal, the defendant assigned the district court’s consider-
    ation of this information, which included confidential mental
    health information provided by DCS, as reversible error. 34
    However, we found the district court had given adequate notice
    to the defendant of its intent to consider such evidence to sat-
    isfy his due process rights. 35
    Additionally, when the bill of exceptions was completed in
    that case, the DCS records were not included. As a result, we
    determined that in our de novo review, we could request and
    consider the additional documents just as the district court had
    requested and considered them. 36 In reaching this determina-
    tion, we noted that our request of these documents did not
    indicate in advance how we would rule on appeal but merely
    followed our statutory requirements for review and honored the
    intent of the Legislature to provide “‘the most scrupulous stan-
    dards of fairness and uniformity’” in reviewing the imposition
    of a sentence of death. 37
    30
    Dunster, supra note 16.
    31
    Id. 32 Id.
    33
    Id. 34 Id.
    35
    Id. 36 Id.
    37
    Id. at 372,
    631 N.W.2d at 913.
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    Dunster neither explicitly nor implicitly required a lower
    court to receive and review documents of a defendant’s prior
    incarceration. Instead, it only evaluated the process of a district
    court seeking to consider specific documents during a sentenc-
    ing proceeding and our ability to review the same information
    upon which the lower court relied. 38 Accordingly, Dunster did
    not add further requirements for the preparation of a presen-
    tence investigation report under § 29-2261(3).
    Because the district court complied with its duties under
    § 29-2261(1) in requesting the presentence investigation and
    report, because the presentence report included the requisite
    analysis of the § 29-2261(3) elements, and because there is no
    requirement that a sentencing court must request access to spe-
    cific § 83-178 DCS records, the district court did not err by not
    requesting that the DCS records be included in the presentence
    investigation report.
    Sufficiency of Safeguards to
    Prevent Arbitrary Results
    Schroeder claims Nebraska’s death penalty is unconstitu-
    tional as applied to him under the 8th and 14th Amendments
    to the U.S. Constitution and article I, §§ 3, 9, and 15, of
    the Nebraska Constitution. Schroeder argues that insufficient
    safeguards exist to prevent arbitrary results when, as here, a
    defendant waives his right to counsel and refuses to introduce
    mitigating or proportionality evidence or argument.
    [19,20] An accused has a state and federal constitutional
    right to be represented by an attorney in all critical stages of a
    criminal prosecution which can lead to a sentence of confine-
    ment. 39 However, a defendant may waive this right to counsel
    38
    Dunster, supra note 16.
    39
    See, U.S. Const. amends. VI and XIV; Neb. Const. art. I, § 11; Scott v.
    Illinois, 
    440 U.S. 367
    , 
    99 S. Ct. 1158
    , 
    59 L. Ed. 2d 383
    (1979); Argersinger
    v. Hamlin, 
    407 U.S. 25
    , 
    92 S. Ct. 2006
    , 
    32 L. Ed. 2d 530
    (1972); Jenkins,
    supra note 2; State v. Wilson, 
    252 Neb. 637
    , 
    564 N.W.2d 241
    (1997);
    State v. Dean, 
    246 Neb. 869
    , 
    523 N.W.2d 681
    (1994), overruled on other
    grounds, State v. Burlison, 
    255 Neb. 190
    , 
    583 N.W.2d 31
    (1998).
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    so long as the waiver is made knowingly, voluntarily, and
    intelligently. 40
    [21-23] The same constitutional provisions that provide
    a defendant the right to counsel also guarantee the right of
    the accused to represent himself or herself. 41 This right to
    self-representation plainly encompasses certain specific rights
    of the defendant to have his voice heard, including that the
    pro se defendant must be allowed to control the organiza-
    tion and content of his own defense. 42 We have previously
    explained that such control may include a waiver of the right
    to present mitigating evidence during sentencing in a death
    penalty case. 43
    Schroeder does not challenge the validity of his waiver of
    counsel for the penalty phase or his election not to present miti-
    gating evidence or proportionality argument. Instead, Schroeder
    argues that the exercise of the right to self-­representation
    and, derived therefrom, the right to waive the presentation
    of evidence and argument conflicted with the constitutional
    restrictions against cruel and unusual punishment. Specifically,
    Schroeder addresses the effect such waivers have on the pro-
    portionality review by the sentencing panel. To establish the
    cruelty and unusualness of such punishment, Schroeder notes
    first that the proportionality requirement under Neb. Rev.
    Stat. §§ 29-2521.01 to 29-2521.04 (Cum. Supp. 2018) only
    requires the sentencing panel to review those cases in which
    the death penalty was imposed. Schroeder also asserts propor-
    tionality review is further limited depending on whether jury
    determinations in the reviewed cases were waived because,
    40
    Jenkins, supra note 2; State v. Hessler, 
    274 Neb. 478
    , 
    741 N.W.2d 406
         (2007).
    41
    Faretta v. California, 
    422 U.S. 806
    , 
    95 S. Ct. 2525
    , 
    45 L. Ed. 2d 562
         (1975); Jenkins, supra note 2; Wilson, supra note 39; State v. Green,   
    238 Neb. 328
    , 
    470 N.W.2d 736
    (1991).
    42
    McKaskle v. Wiggins, 
    465 U.S. 168
    , 
    104 S. Ct. 944
    , 
    79 L. Ed. 2d 122
         (1984); Dunster, supra note 16; Wilson, supra note 39.
    43
    Dunster, supra note 16.
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    when they are waived, a sentencing panel is required to issue
    written findings of fact as to any proven aggravating circum-
    stances, but when there is no waiver, the jury does not issue
    such analysis. Schroeer argues that when a defendant waives
    counsel and refuses to meaningfully participate, the record on
    which the panel makes its proportionality determination is lim-
    ited to what it requests and the State presents, which has the
    potential to be limited and biased in favor of the imposition of
    a death sentence.
    [24,25] Because a death sentence is different from any
    other criminal penalty 44 and no system based on human judg-
    ment is infallible, we have taken, and should continue to
    take, the extra step to ensure fairness and accuracy with the
    imposition of the death penalty. 45 Taking this into account,
    the Legislature has enacted a statutory scheme to provide
    additional safeguards, 46 and in interpreting these statutes, we
    have followed the fundamental principle of statutory construc-
    tion that penal statutes are to be strictly construed in favor of
    the defendant. 47
    [26] Part of this statutory scheme, as explained, requires a
    court to order a presentence investigation report. 48 The sentenc-
    ing panel must consider this report in reaching its sentence.
    Thus, contrary to Schroeder’s argument, even if the State pre­
    sents evidence in favor of a specific sentence and the defendant
    declines to present contrary evidence, the court receives and
    must consider independent information from the report.
    [27,28] In a death penalty case, the sentencing panel is
    required to review this report and determine whether it contra-
    dicts the State’s evidence of aggravating factors and whether
    any mitigating circumstances exist, including specifically
    44
    State v. Hochstein and Anderson, 
    262 Neb. 311
    , 
    632 N.W.2d 273
    (2001).
    45
    Id. 46 Neb.
    Rev. Stat. §§ 29-2519 to 29-2546 (Cum. Supp. 2018).
    47
    Hochstein and Anderson, supra note 44.
    48
    §§ 29-2261(1) and 29-2521(2).
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    delineated statutory mitigators. 49 While the State must prove the
    aggravating circumstances beyond a reasonable doubt, 50 there
    is no burden of proof with regard to mitigating circumstances. 51
    Accordingly, the panel’s evaluation of the independently com-
    piled presentence investigation report and any evidence the
    defendant chooses to introduce is under the less restrictive
    mitigation standard and provides another safeguard to ensure
    fairness and accuracy in a death penalty determination.
    [29-32] Once the panel makes its determinations about the
    existence of aggravating and mitigating circumstances, the
    panel is then required to undertake a proportionality review.
    This review looks at whether the sentence of death is excessive
    or disproportionate to the penalty imposed in similar cases,
    considering both the crime and the defendant. 52 Proportionality
    review is not constitutionally mandated. 53 It exists in Nebraska
    by virtue of §§ 29-2521.01 to 29-2521.04, which direct this
    court to conduct a proportionality review in each appeal in
    which a death sentence is imposed. 54 A court’s proportionality
    review spans all previous cases in which a sentence of death is
    imposed and is not dependent on which cases are put forward
    by the parties. 55
    Schroeder takes issue with proportionality review requiring
    a panel to compare only those cases in which the death penalty
    was imposed. 56 Instead, Schroeder argues the statutory scheme
    explicitly requires review of all homicide cases regardless of
    the resulting sentence.
    49
    §§ 29-2521 to 29-2523.
    50
    Torres, supra note 3.
    51
    State v. Vela, 
    279 Neb. 94
    , 
    777 N.W.2d 266
    (2010); State v. Victor, 
    235 Neb. 770
    , 
    457 N.W.2d 431
    (1990).
    52
    § 29-2522(3).
    53
    State v. Gales, 
    269 Neb. 443
    , 
    694 N.W.2d 124
    (2005).
    54
    Id. 55 See
    id.
    56
    See 
    State v. Palmer, 
    224 Neb. 282
    , 
    399 N.W.2d 706
    (1986), overruled on
    other grounds, State v. Chambers, 
    233 Neb. 235
    , 
    444 N.W.2d 667
    (1989).
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    It is unclear how Schroeder is arguing this fits under his
    assignment alleging unconstitutionality in the interplay of
    his waiver of counsel and election not to present evidence
    or argument with Nebraska’s capital sentencing scheme. The
    introduction of further evidence or whether or not Schroeder
    was represented by counsel does not affect what previous
    cases the panel was required to consider. In any case, we
    decline Schroeder’s invitation to overrule our decision in State
    v. Palmer 57 which interpreted §§ 29-2521.01 to 29-2521.04 to
    only require review of previous cases in which the death pen-
    alty was imposed.
    Additionally, we are unconvinced by Schroeder’s claim that
    the proportionality review is unconstitutionally flawed due
    to having less analysis of the reviewed cases in which a jury
    determines the existence of the aggravating circumstance than
    of the reviewed cases in which a sentencing panel makes the
    determination. Again, it is unclear how Schroeder relates this
    alleged flaw to this assignment. If Schroeder is claiming that
    waiver of counsel and lack of argument would prohibit the
    panel from taking into account that previous aggravation deter-
    minations were decided by juries, this information would be
    apparent from the previous opinions and would be able to be
    considered by the panel independently of whether the defend­
    ant or an advocate explained such difference to the panel.
    [33,34] Moreover, even when a jury determines the exis-
    tence of an aggravating circumstance, a sentencing panel is
    required to put in writing its consideration of (1) whether the
    determined aggravating circumstance justifies the imposition
    of a sentence of death, (2) whether mitigating circumstances
    exist, and (3) whether a sentence of death would be excessive
    or disproportionate to penalties imposed in similar cases. 58 This
    writing must specifically refer to the aggravating and mitigat-
    ing circumstances weighed in the determination of the panel. 59
    57
    Id. See, also,
    State v. Gales, supra note 53.
    58
    § 29-2522.
    59
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    As such, the basis of Schroeder’s argument that cases where
    a jury determines the existence of aggravating circumstances
    provide insufficient information for comparison in a propor-
    tionality review is without merit.
    [35-38] Considering all of the above, Nebraska’s capital
    sentencing scheme provides additional statutory steps and con-
    siderations to ensure fairness and accuracy, and these safe-
    guards exist regardless of a defendant’s strategy at the pen-
    alty phase. Due to this statutory scheme, a defendant cannot
    “choose” the death penalty. The sentencing decision rests
    with the court alone. 60 In order to exercise this authority, the
    statutory scheme requires that a sentencing panel consider not
    only evidence and argument presented by the parties but also
    an independently compiled presentence investigation report to
    determine whether the alleged aggravating circumstance exists,
    determine whether any mitigating factors are present which
    would weigh against the imposition of the death penalty, and
    conduct a proportionality review weighing the aggravating and
    mitigating factors and comparing the facts to previous cases
    where the death penalty was imposed. 61 These considerations
    exist and are weighed regardless of the evidence presented by
    the parties or their arguments.
    [39,40] A defendant is entitled to present a defense and is
    guaranteed the right to choose the objectives for that defense. 62
    As previously stated, the self-represented defendant must be
    allowed to control the organization and content of his own
    defense. 63 However, Schroeder suggests that in a death pen-
    alty case, the substantial nature of the proceedings requires
    an advocate in opposition to a sentence of death irrespective
    of the defendant’s chosen objective. To this end, he suggests
    §§ 29-2519 to 29-2546 implicitly require the appointment of a
    60
    Dunster, supra note 16.
    61
    See Torres, supra note 3.
    62
    McCoy v. Louisiana, ___ U.S. ___, 
    138 S. Ct. 1500
    , 
    200 L. Ed. 2d 821
         (2018); Jenkins, supra note 2.
    63
    Dunster, supra note 16.
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    guardian ad litem to present evidence and argument as to why
    the death penalty should not be imposed.
    [41] This suggestion is similar to that addressed in Dunster. 64
    The defendant therein had waived trial counsel for the penalty
    stage and chose not to present any mitigating evidence. On
    appeal, he claimed the court should have appointed “amicus
    counsel” to advocate against the imposition of the death pen-
    alty by presenting evidence and “‘argu[ing] for life,’” which is
    identical to the role Schroeder now envisions for an appointed
    guardian ad litem. 65 As noted in Dunster, when a defendant
    waives counsel and the presentation of mitigating evidence,
    the appointment of an advocate to present evidence and argue
    against the imposition of a sentence overrides that defendant’s
    constitutional right to control the organization and content of
    his or her own defense during sentencing.
    [42,43] A criminal defendant has the right to waive counsel
    and present his or her own defense. 66 In a death penalty case,
    this includes the right of the defendant to elect not to present
    additional evidence or argument during the penalty proceed-
    ings. Even if a defendant makes such waiver and election, the
    Legislature has enacted safeguards to ensure fairness and accu-
    racy in the resulting sentence. As explained above, these safe-
    guards apply regardless of the defense strategy an individual
    defendant implements. Therefore, Schroeder’s assignment that
    Nebraska’s capital sentencing scheme is unconstitutional due
    to insufficient safeguards to prevent arbitrary results when a
    defendant waives counsel and elects not to present evidence or
    argument fails.
    Excessiveness and
    Proportionality Review
    [44,45] In reviewing a sentence of death, we conduct
    a de novo review of the record to determine whether the
    64
    Id. 65 Id.
    at 
    361, 631 N.W.2d at 906
    .
    66
    See Dunster, supra note 16.
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    aggravating and mitigating circumstances support the imposi-
    tion of the death penalty. 67 In so doing, we consider whether
    the aggravating circumstances justify imposition of a sentence
    of death and whether any mitigating circumstances found to
    exist approach or exceed the weight given to the aggravat-
    ing circumstances. 68
    We first note Schroeder does not contest the factual basis
    for the § 29-2523(1)(a) aggravation allegation that Schroeder
    was convicted of Albers’ murder. It is undisputed that in 2006,
    Schroeder murdered Albers, who was at the time Schroeder’s
    75-year-old previous employer. It is also undisputed that
    Albers was robbed and that Schroeder had made the decision
    to kill Albers days before the robbery. Schroeder threatened
    and beat Albers, tied him up, threw him in the back of a
    pickup, and dumped him in an abandoned well, leaving him
    for dead. Based upon our de novo review, we determine this
    murder conviction, which was proved beyond a reasonable
    doubt at the sentencing hearing, is sufficient as an aggravating
    circumstance under § 29-2523(1)(a) to justify the imposition
    of the death penalty. In coordination with our analysis con-
    cerning the panel’s mitigating circumstance findings, we also
    agree with the panel’s determination that the applicable statu-
    tory and nonstatutory circumstances apparent from the record
    do not approach or exceed the aggravating circumstance in
    this case.
    [46-48] In addition, we are required, upon appeal, to deter-
    mine the propriety of a death sentence by conducting a propor-
    tionality review, comparing the aggravating and mitigating cir-
    cumstances with those present in other cases in which a court
    imposed the death penalty. 69 The purpose of this review is to
    ensure that the sentences imposed in this case are no greater
    than those imposed in other cases with the same or similar
    67
    Torres, supra note 3.
    68
    Id. 69 Id.
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    circumstances. 70 Our proportionality review looks only to other
    cases in which the death penalty has been imposed and requires
    us to compare the aggravating and mitigating circumstances of
    the case on appeal with those present in those other cases. 71
    In this case, we have reviewed our relevant decisions on
    direct appeal from other cases in which the death penalty was
    imposed. 72
    Like the sentencing panel, we find Dunster particularly
    pertinent to our review. 73 The defendant therein was convicted
    of murdering his cellmate by strangling him with an electrical
    cord. 74 The defendant had previously been convicted of the
    earlier murder of a woman while attempting to collect a debt
    from her husband, and he had confessed to a different murder
    of another inmate while incarcerated for the first murder. 75
    At the penalty phase, the State alleged a single aggravating
    circumstance of § 29-2523(1)(a) and presented evidence of
    the two previous killings. 76 After the trial court sentenced the
    defendant to death, we affirmed. 77 Such factual basis is similar
    to that in the instant case. As did the defendant in Dunster,
    Schroeder murdered his cellmate by strangulation. Schroeder’s
    previous murder of Albers was also pursuant to a plan to take
    money from his victim.
    70
    See
    id. 71 Id.
    72
    See, e.g., Jenkins, supra note 2; Torres, supra note 3; State v. Ellis, 
    281 Neb. 571
    , 
    799 N.W.2d 267
    (2011); Hessler, supra note 40; Dunster, supra
    note 16; State v. Lotter, 
    255 Neb. 456
    , 
    586 N.W.2d 591
    (1998), modified
    on denial of rehearing 
    255 Neb. 889
    , 
    587 N.W.2d 673
    (1999); State v.
    Williams, 
    253 Neb. 111
    , 
    568 N.W.2d 246
    (1997); State v. Ryan, 
    233 Neb. 74
    , 
    444 N.W.2d 610
    (1989); State v. Joubert, 
    224 Neb. 411
    , 
    399 N.W.2d 237
    (1986); State v. Otey, 
    205 Neb. 90
    , 
    287 N.W.2d 36
    (1979).
    73
    Dunster, supra note 16.
    74
    Id. 75 Id.
    76
    Id. 77 Id.
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    Schroeder attempts to differentiate his case from Dunster
    by emphasizing that while only one aggravating circumstance
    was alleged in Dunster, the allegation therein concerned
    two previous murders. Additionally, Schroeder argues those
    underlying murders were committed with more serious facts,
    including that there was suspected sexual assault of one of
    the victims.
    First, it is not evident that the underlying murders in Dunster
    included any more or less serious facts surrounding their
    execution. Schroeder threatened, beat, and robbed Albers and
    threw him bound and alive into a well to die. The murders the
    defendant in Dunster committed involved binding, beating,
    killing, and possible sexual assault. In both cases, the defend­
    ants acted with violence toward the persons.
    [49,50] Additionally, while there were two underlying mur-
    ders in Dunster, this does not mean Dunster cannot be used
    in a proportionality review. A proportionality review does not
    require that a court “color match” cases precisely. 78 It would
    be virtually impossible to find two murder cases which are the
    same in all respects. 79 Instead, the question is simply whether
    the cases being compared are sufficiently similar, considering
    both the crime and the defendant, to provide the court with a
    useful frame of reference for evaluating the sentence in this
    case. 80 As the factual connections show, Dunster is sufficiently
    similar for purposes of evaluating proportionality.
    [51-53] Along the same lines, Schroeder attempts to distin-
    guish his case from others cited by the sentencing panel and
    reviewed on appeal by noting that the majority of those cases
    had multiple aggravating factors. However, we have established
    that one aggravating circumstance may be sufficient under our
    statutory system for the imposition of the death penalty. 81 In
    78
    Ellis, supra note 72.
    79
    Id. 80 Id.
    81
    Dunster, supra note 16.
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    our proportionality review, the evaluation of whether the death
    penalty should be imposed in a specific case is not a mere
    counting process of “X” number of aggravating circumstances
    and “Y” number of mitigating circumstances and, instead, asks
    whether the reviewed cases are sufficiently similar to provide
    a useful reference for that evaluation. 82 Thus, even though
    other cases may involve additional or different aggravating
    circumstances, they may still be sufficiently similar to provide
    such reference.
    Having reviewed our previous cases which have affirmed
    the imposition of a death penalty and compared the aggra-
    vating and mitigating circumstances present in those cases,
    we are persuaded that the sentence imposed in this case is
    not greater than those imposed in other cases with the same
    or similar circumstances. Accordingly, we affirm Schroeder’s
    death sentence.
    CONCLUSION
    In consideration of all of the above, Schroeder’s conviction
    and sentence for first degree murder are affirmed.
    Affirmed.
    Freudenberg, J., not participating.
    82
    See, Ellis, supra note 72; Dunster, supra note 16.