Commonwealth v. Cotto , 471 Mass. 97 ( 2015 )


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    SJC-11761
    COMMONWEALTH   vs.   ERICK COTTO, JR.
    Hampden.    December 4, 2014. - April     , 2015.
    Present:     Gants, C.J., Spina, Cordy, Botsford, Duffly, Lenk,
    & Hines, JJ.
    Controlled Substances. Constitutional Law, Plea, Conduct of
    government agents, Subpoena, Self-incrimination. Due
    Process of Law, Plea, Disclosure of evidence, Presumption.
    Practice, Criminal, Plea, Conduct of government agents,
    Disclosure of evidence, Presumptions and burden of proof,
    Subpoena. Evidence, Guilty plea, Certificate of drug
    analysis, Exculpatory, Disclosure of evidence, Presumptions
    and burden of proof, Testimonial privilege. Witness,
    Subpoena, Self-incrimination, Privilege. Privileged
    Communication.
    Indictments found and returned in the Superior Court
    Department on June 14, 2007.
    A motion to withdraw guilty pleas, filed on April 25, 2013,
    was heard by C. Jeffrey Kinder, J.
    The Supreme Judicial Court granted an application for
    direct appellate review.
    Rebecca A. Jacobstein, Committee for Public Counsel
    Services, for the defendant.
    Katherine A. Robertson, Assistant District Attorney, for
    the Commonwealth.
    2
    Luke Ryan, for Rafael Rodriguez, amicus curiae, submitted a
    brief.
    Glynis MacVeety, for Deon Charles, amicus curiae, submitted
    a brief.
    SPINA, J.   On June 14, 2007, a Hampden County grand jury
    indicted the defendant, Erick Cotto, Jr., on charges of
    trafficking in cocaine (twenty-eight to one hundred grams),
    G. L. c. 94C, § 32E (b) (2); unlawful possession of ammunition
    without a firearm identification card, G. L. c. 269, § 10 (h);
    and being an armed career criminal, G. L. c. 269, § 10G (b).
    Sonja Farak, then a chemist at the Department of Public Health's
    State Laboratory Institute in Amherst (Amherst drug lab), tested
    the substances in the defendant's case on June 8, 2007, and
    signed the certificates of drug analysis (drug certificates).1
    Pursuant to a plea agreement, the defendant pleaded guilty on
    April 13, 2009, to trafficking in cocaine (fourteen to twenty-
    eight grams), and unlawful possession of ammunition.2
    1
    Sonja Farak was a chemist for the Department of Public
    Health from July, 2003, until January 19, 2013. During the
    first year of her employment, she worked at the William A.
    Hinton State Laboratory Institute in the Jamaica Plain section
    of Boston. After that, Farak worked at the Department of Public
    Health's State Laboratory Institute in Amherst (Amherst drug
    lab).
    2
    With respect to the trafficking charge, the   defendant was
    sentenced to from five years to five years and one   day in State
    prison. With respect to the ammunition charge, he    was sentenced
    to one year in a house of correction, to be served   concurrently
    with the sentence on the trafficking charge.
    3
    On April 1, 2013, a State grand jury indicted Farak on four
    counts of tampering with evidence, G. L. c. 268, § 13E; four
    counts of theft of a controlled substance (cocaine) from a
    dispensary, G. L. c. 94C, § 37; and two counts of unlawful
    possession of a class B substance (cocaine), G. L. c. 94C, § 34.
    Approximately three weeks later, the defendant filed a motion to
    withdraw his guilty pleas pursuant to Mass. R. Crim. P. 30 (b),
    as appearing in 
    435 Mass. 1501
     (2001).   He claimed that Farak
    was a government agent by virtue of her role at the Amherst drug
    lab, that her misconduct was widespread and egregious, and that
    such misconduct antedated his guilty pleas.   As a consequence,
    the defendant asserted that because his guilty pleas were based,
    in part, on an assumption that the drug certificates were
    truthful and accurate, his decision to plead guilty was not
    knowing, voluntary, and intelligent.   The defendant further
    claimed that Farak's misconduct constituted newly discovered
    evidence that would have had a significant impact on his
    decision to plead guilty and cast serious doubt on the justice
    of his convictions.3   On October 30, 2013, a Superior Court judge
    3
    In an affidavit dated April 19, 2013, the defendant's
    trial counsel stated that, at the time she advised her client to
    plead guilty, she was not aware of Farak's misconduct. If she
    had been aware of such misconduct prior to the defendant's
    pleas, she would not have advised him to plead guilty. Instead,
    she would have advised the defendant to either negotiate for a
    better plea offer or go to trial.
    4
    denied the defendant's motion.   Farak pleaded guilty to all ten
    charges on January 6, 2014.
    The defendant appealed, and we granted his application for
    direct appellate review.   The defendant now contends that the
    judge abused his discretion by (1) failing to afford the
    defendant the benefit of the conclusive presumption articulated
    in Commonwealth v. Scott, 
    467 Mass. 336
    , 352-353 (2014), that
    egregious misconduct by Farak occurred in the defendant's case;
    (2) ignoring direct and circumstantial evidence of misconduct by
    Farak that antedated the entry of the defendant's guilty pleas;
    and (3) finding that the defendant would have pleaded guilty
    notwithstanding Farak's misconduct.   The defendant also claims
    that the judge erred by quashing a subpoena that had been issued
    to Farak's spouse, Nikki Lee, where she was a necessary witness
    for the defense.   For the reasons set forth below, we vacate the
    order denying the defendant's motion to withdraw his guilty
    pleas, and we conclude that, given the Commonwealth's failure to
    thoroughly investigate the matter of Farak's misconduct at the
    Amherst drug lab, the defendant is entitled to a measure of
    relief, as will be described in detail.4   We remand the case for
    further proceedings in accordance with this opinion.
    4
    We acknowledge the amicus briefs submitted by Rafael
    Rodriguez and Deon Charles, defendants in two other Amherst drug
    lab cases whose motions to withdraw their respective guilty
    pleas were denied. See note 5, infra. Their appeals have been
    5
    1.   Background on the Amherst drug lab.5    The Amherst drug
    lab began operation in 1987 with the primary function of
    analyzing suspected controlled substances for law enforcement
    agencies involved in the prosecution of criminal cases in
    western Massachusetts.6    As of January, 2013, there were four
    employees at the facility, and each one could access the
    evidence safe by means of an electronic card or a key.       On
    January 17, 2013, the evidence officer at the Amherst drug lab,
    Sharon Salem, was attempting to match drug certificates with the
    corresponding samples when she realized that she was missing the
    samples in two cases.     Records reflected that Farak had
    completed testing on those samples earlier in the month and had
    confirmed that the substances were cocaine.      On January 18,
    stayed by the Appeals Court pending our decision in the present
    case.
    5
    In the fall of 2013, the judge in the present case
    conducted an evidentiary hearing on postconviction motions filed
    by fifteen defendants who claimed that alleged criminal conduct
    by Farak rendered their guilty pleas to various drug charges
    unknowing, unintelligent, and involuntary, and that this newly
    discovered evidence cast doubt on the justice of their
    convictions. The evidence presented at the hearing was limited
    to (1) the timing and scope of Farak's alleged criminal conduct;
    (2) the timing and scope of conduct underlying negative findings
    in an October 10, 2012, quality assurance audit of the Amherst
    drug lab by the State police (see note 11, infra); and (3) the
    extent to which Farak's alleged criminal conduct and the audit
    findings might relate to the testing of drug evidence in the
    fifteen defendants' cases.
    6
    On July 1, 2012, the responsibility for oversight of the
    Amherst drug lab was transferred from the Department of Public
    Health to the State police.
    6
    Salem reported the missing evidence to her supervisor, James
    Hanchett, who searched Farak's work station and discovered,
    among other items, a manila envelope containing the packaging
    for the two missing samples, which had been cut open.    Testing
    of the substances in the packaging was negative for cocaine,
    contrary to Farak's earlier analysis.
    Hanchett immediately contacted the State police, who shut
    down the Amherst drug lab and began an investigation.    They
    discovered two additional case envelopes in a temporary storage
    locker used by Farak, a location where evidence was not allowed
    to be stored overnight.    Although each envelope was supposed to
    contain suspected cocaine, neither did, and a search for those
    substances was unsuccessful.    Investigators also interviewed
    Farak's colleagues who said that, beginning in September, 2012,
    they observed a change in Farak's behavior, including frequent
    unexplained absences from her work station and a decrease in
    productivity.
    On January 19, 2013, the State police forensic services
    conducted an inventory of all drug evidence at the Amherst drug
    lab.    Only the four above-described samples were missing.     A
    similar inventory conducted approximately four months earlier
    had not uncovered any missing samples.    Also on January 19, the
    State police searched Farak's vehicle pursuant to a warrant and
    seized, among other items, manila envelopes bearing case
    7
    numbers, paperwork relating to the Amherst drug lab, a plastic
    bag containing a white powdery substance and a brown tar-like
    substance, a plastic bag containing assorted pills, and
    photocopies of three newspaper articles about individuals who
    had been investigated, charged, or sentenced for the illegal
    possession or theft of controlled substances.7   Attached to one
    of the articles was a handwritten note stating, "Thank [G]od I'm
    not a law enforcement officer" (emphasis in original).
    Farak was arrested at her home that same day.   She was
    charged by criminal complaint in the District Court with
    unlawful possession of a class A substance (heroin), unlawful
    possession of a class B substance (cocaine), and two counts of
    tampering with evidence.   On January 25, 2013, the State police
    searched a tote bag that had been seized from Farak's work
    station pursuant to a warrant.   The bag contained a variety of
    substances that could be used to dilute or replace cocaine
    (soap, baking soda, soy candle flakes, and oven-baked clay),
    7
    One of the newspaper articles, dated March 29, 2011, had
    been printed from a computer on September 20, 2011, and was a
    story about the illegal possession of steroids by law
    enforcement officers. A second newspaper article, dated
    October 25, 2011, had been printed from a computer on
    October 28, 2011, and was a story about a Pittsfield pharmacist
    being sentenced to three years in prison for stealing OxyContin
    from her workplace. The article mentioned that the pharmacist
    had replaced the OxyContin with other medications. A third
    newspaper article, dated December 2, 2011, had been printed from
    a computer on December 6, 2011, and was a story about a former
    San Francisco police department drug laboratory technician who
    stole cocaine from her workplace.
    8
    other items commonly used in the drug trade (plastic laboratory
    dishes, waxed paper, and fragments of copper wire), and several
    evidence bags that had been cut open.   The evidence bags bore
    diverse dates from December 16, 2012, to January 6, 2013.
    On April 1, 2013, a State grand jury indicted Farak on four
    counts of tampering with evidence at the Amherst drug lab, four
    counts of stealing cocaine from that facility, and two counts of
    unlawful possession of cocaine.   While proceedings were ongoing
    in the Superior Court with respect to these charges, four
    additional cases surfaced in which it seemed, based on
    retesting, that Farak may have removed cocaine from samples that
    were submitted to the Amherst drug lab for analysis between June
    15 and October 10, 2012, and replaced at least some of the
    cocaine with a counterfeit substance.   It is not clear from the
    record why this particular evidence was selected for retesting.
    Nonetheless, it does appear that no charges were brought against
    Farak with respect to these four additional cases.   On January
    6, 2014, Farak pleaded guilty to all ten charges.8
    8
    With respect to the first count of tampering with evidence
    (Count I), Farak was sentenced to two and one-half years in a
    house of correction, with eighteen months to serve, and the
    balance suspended with probation for five years, with special
    conditions. Farak was given the same sentence on the second and
    third counts of tampering with evidence, as well as on three
    counts of theft of a controlled substance, each sentence to run
    concurrently with the sentence on Count I. With respect to each
    of the two counts of unlawful possession of a class B substance,
    Farak was sentenced to serve one year in a house of correction,
    each sentence to run concurrently with the sentence on Count I.
    9
    2.     Factual and procedural history.   In the spring of 2007,
    Springfield police Officer Thomas Nehmer discovered, through the
    use of a confidential informant, that the defendant was selling
    cocaine.    On May 4, 2007, based on information received from the
    informant regarding the defendant's involvement in an upcoming
    drug deal, the police established surveillance at the time and
    place of the transaction.   When the defendant arrived as
    predicted, he was secured by police and found to be in
    possession of two cellular telephones, ninety-one dollars, and
    what appeared to be approximately eight grams of cocaine.    He
    was placed under arrest and transported to the police station.
    Following a waiver of his Miranda rights, the defendant told
    officers that in his bedroom at his residence were packaging
    materials, scales, and approximately thirty grams of cocaine.
    Officer Nehmer applied for and was granted a search warrant.
    When officers searched the defendant's residence, they
    discovered fifty-eight rounds of .22 caliber ammunition, scales,
    cutting agents, and two bags containing substances that appeared
    to be cocaine and weighed approximately forty-four grams.    The
    substances were tested by Farak at the Amherst drug lab on
    With respect to the fourth count of tampering with evidence and
    the fourth count of theft of a controlled substance, Farak was
    sentenced to five years' probation, to run concurrently with her
    probation on the other charges.
    10
    June 8, 2007.   According to the drug certificates that she
    signed, each substance tested positive for cocaine.9
    On April 13, 2009, after engaging in a thorough colloquy
    with the judge and before Farak's misconduct had become known,
    the defendant pleaded guilty to trafficking in cocaine (fourteen
    to twenty-eight grams), and unlawful possession of ammunition.
    The bases for his subsequent motion to withdraw his guilty pleas
    were twofold.   First, the alleged criminal conduct by Farak at
    the Amherst drug lab rendered his guilty pleas unknowing,
    unintelligent, and involuntary.   Second, such misconduct
    constituted newly discovered evidence that cast real doubt on
    the justice of his convictions.   The judge considered each
    contention in turn.
    In deciding whether the defendant's pleas were knowing,
    voluntary, and intelligent, the judge relied on the analysis
    articulated in Ferrara v. United States, 
    456 F.3d 278
    , 290 (1st
    Cir. 2006).10   He stated that a defendant seeking to set aside a
    guilty plea as involuntary must show that (1) the government or
    its agents committed some egregiously impermissible conduct that
    9
    According to the Commonwealth, the drugs seized from the
    defendant have been destroyed.
    10
    At the time the judge ruled on the defendant's motion to
    withdraw his guilty pleas, he did not have the benefit of our
    decision in Commonwealth v. Scott, 
    467 Mass. 336
     (2014), which
    also relied on the analysis set forth in Ferrara v. United
    States, 
    456 F.3d 278
    , 290 (1st Cir. 2006).
    11
    antedated the entry of the plea, and (2) the misconduct was
    material to the defendant's choice to plead guilty.   See 
    id.
    With regard to the first part of the inquiry, the judge
    concluded that, given Farak's role at the Amherst drug lab, she
    must be deemed to be an agent of the Commonwealth.    Next, the
    judge considered whether Farak's alleged misconduct antedated
    the defendant's guilty pleas on April 13, 2009.    The judge said
    that, although there was "powerful evidence" that Farak had
    engaged in egregiously impermissible conduct by stealing cocaine
    and replacing it with other substances, he was not persuaded
    that she was doing so at the time of the defendant's guilty
    pleas.    Therefore, the defendant failed to establish that
    Farak's misconduct antedated his guilty pleas.    Further, in the
    judge's view, the negative findings made during an October,
    2012, quality assurance audit of the Amherst drug lab were
    disconcerting, but there was no evidence that these general
    deficiencies had any bearing on the testing performed in the
    defendant's case.11   As such, the findings of the audit did not
    11
    On October 10, 2012, the State police conducted a quality
    assurance audit of the Amherst drug lab. It was a routine
    matter in the sense that quality assurance audits are conducted
    at all State police laboratories every year, but this facility
    never had been audited. See note 6, supra. Among other
    purposes, the audit was designed to determine what steps the
    Amherst drug lab would have to take in order to meet
    accreditation standards required by the American Society of
    Crime Lab Directors/Laboratory Accreditation Board. The Amherst
    drug lab had not been accredited since it began operation in
    1987 and, in fact, all State police laboratories operated
    12
    amount to the kind of egregiously impermissible government
    conduct contemplated by the Ferrara case.
    The judge then considered the second part of the Ferrara
    inquiry, namely whether Farak's misconduct would have been
    material to the defendant's decision to plead guilty.     The judge
    stated that there was no evidence that the test results in this
    case were inaccurate, or that Farak was involved in any
    misconduct at the time of the defendant's guilty pleas.
    Moreover, he continued, there were good reasons for the
    defendant to accept the plea agreement.   Given the strength of
    the Commonwealth's case (including the defendant's own
    incriminating statements), the significant benefit the defendant
    received from the plea agreement, and the absence of any
    without accreditation prior to 2002. The negative findings in
    the October, 2012, audit of the Amherst drug lab included the
    following: chain of custody with respect to evidence kept in
    short-term overnight storage was not documented appropriately,
    and evidence retained in such storage was not sealed properly;
    evidence seals were initialed, but not dated, by the chemists;
    variances between weights of substances on arrival and weights
    at testing were not documented; and inventory discrepancies were
    not verified. In addition, so-called "reagents" were not
    regularly tested, and known drug standards were not verified on
    a daily basis. The audit team recommended steps to remediate
    each of these problems, and personnel at the Amherst drug lab
    took measures to address the negative findings. Cathleen
    Morrison, a member of the audit team and an author of the audit
    report, testified at the evidentiary hearing, see note 5, supra,
    that the audit did not raise any questions regarding the
    reliability of the testing performed at the Amherst drug lab.
    The judge concluded that, although the negative findings in the
    audit "reflect[ed] a lax atmosphere in which theft of controlled
    substances could go undetected for a period of time, the audit
    did not reveal any unreliable testing."
    13
    evidence that Farak's misconduct affected the drug testing in
    the defendant's case, the judge concluded that Farak's
    misconduct would not have been material to the defendant's
    decision to plead guilty, even if such misconduct had antedated
    the defendant's pleas.   The judge also found that the negative
    audit of the Amherst drug lab failed to satisfy the threshold of
    materiality required to invalidate the defendant's guilty pleas.
    Accordingly, based on the totality of the circumstances, the
    judge concluded that the defendant had failed to establish that
    his guilty pleas were not knowingly, intelligently, and
    voluntarily made.
    Finally, the judge considered whether Farak's misconduct at
    the Amherst drug lab constituted newly discovered exculpatory
    evidence that cast real doubt on the justice of the defendant's
    convictions.   The judge first determined that there was no
    evidence that the defendant or his attorney was aware of Farak's
    misconduct or the negative audit, or that either reasonably
    could have been discovered at the time of the defendant's pleas.
    Therefore, the judge continued, the evidence of Farak's
    misconduct, in particular, and the administrative problems at
    the Amherst drug lab, in general, qualified as "newly
    discovered."   However, for all of the reasons he already had
    articulated, the judge stated that this newly discovered
    evidence was "not sufficiently weighty, potent, or pertinent to
    14
    the fundamental issues of this case to be worthy of
    consideration at a new trial."
    3.    Standard of review.    A motion to withdraw a guilty plea
    is treated as a motion for a new trial pursuant to Mass. R.
    Crim. P. 30 (b).    Commonwealth v. Furr, 
    454 Mass. 101
    , 106
    (2009).   "Under Mass. R. Crim. P. 30 (b), a judge may grant a
    motion for a new trial any time it appears that justice may not
    have been done.    A motion for a new trial is thus committed to
    the sound discretion of the judge."     Scott, 467 Mass. at 344.
    We review the allowance or denial of a motion to withdraw a
    guilty plea to determine whether the judge abused that
    discretion or committed a significant error of law.     Id.    We
    accept the judge's findings of fact if they are supported by the
    evidence, because the judge who heard the witnesses testify is
    the "final arbiter [on] matters of credibility."     Id., quoting
    Commonwealth v. Schand, 
    420 Mass. 783
    , 787 (1995).
    4.    Discussion.    Due process requires that a plea of guilty
    be accepted only where "the contemporaneous record contains an
    affirmative showing that the defendant's plea was intelligently
    and voluntarily made."     Furr, 454 Mass. at 106, citing Boykin v.
    Alabama, 
    395 U.S. 238
     (1969), and Commonwealth v. Foster, 
    368 Mass. 100
    , 102 (1975).    "A guilty plea is intelligent if it is
    tendered with knowledge of the elements of the charges against
    the defendant and the procedural protections waived by entry of
    15
    a guilty plea."   Scott, 467 Mass. at 345.    See Commonwealth v.
    Duest, 
    30 Mass. App. Ct. 623
    , 630-631 (1991).     "A guilty plea is
    voluntary so long as it is tendered free from coercion, duress,
    or improper inducements."     Scott, supra.   Typically, a motion to
    withdraw a guilty plea will allege a facial defect in the plea
    procedures, but a guilty plea "also may be vacated as
    involuntary because of external circumstances or information
    that later comes to light."    Id., and cases cited.
    We begin by reviewing the framework for analyzing the
    defendant's motion to withdraw his guilty pleas.     In Ferrara,
    
    456 F.3d at 280, 284, 290-293
    , the United States Court of
    Appeals for the First Circuit analyzed whether blatant
    misconduct by the government, discovered more than ten years
    after entry of the defendant's guilty plea, could render such
    plea involuntary.   The prosecutor in Ferrara deliberately
    manipulated a key witness, failed to disclose exculpatory
    evidence, and affirmatively misrepresented the nature of the
    witness's planned testimony.    
    Id. at 291-293
    .   The court
    concluded that when a defendant seeks to vacate a guilty plea as
    a result of underlying government misconduct, rather than a
    defect in the plea procedures, the defendant must show both that
    "egregiously impermissible conduct . . . by government agents
    . . . antedated the entry of his plea," and that "the misconduct
    influenced his decision to plead guilty or, put another way,
    16
    that it was material to that choice."       
    Id. at 290
    .   Relying on
    Ferrara, this court articulated in Scott, 467 Mass. at 346-358,
    a two-prong framework for analyzing a defendant's motion to
    withdraw his guilty plea under Mass. R. Crim. P. 30 (b) in a
    case involving the misconduct of Annie Dookhan, a chemist at the
    William A. Hinton State Laboratory Institute's forensic drug
    laboratory (Hinton drug lab) from 2003 to 2012.      Under the first
    prong of the analysis, a defendant must show egregious
    misconduct by the government that preceded the entry of the
    defendant's guilty plea and that occurred in the defendant's
    case.   Id. at 347-354.   Under the second prong of the analysis,
    a defendant must demonstrate a reasonable probability that he or
    she would not have pleaded guilty had he or she known of the
    government misconduct.    Id. at 354-358.
    We recognized in Scott that, given the breadth and duration
    of Dookhan's malfeasance, it might be impossible for a defendant
    to show the required nexus between the government misconduct and
    the defendant's own case.   Scott, 467 Mass. at 351-352.
    Dookhan's "insidious" misconduct, "which belie[d]
    reconstruction, [was] a lapse of systemic magnitude in the
    criminal justice system."   Id. at 352.     Consequently, we
    established a special evidentiary rule whereby a defendant
    seeking to vacate a guilty plea under rule 30 (b) as a result of
    the revelation of Dookhan's misconduct, and proffering a drug
    17
    certificate from the defendant's case signed by Dookhan on the
    line labeled "Assistant Analyst," would be entitled to "a
    conclusive presumption that egregious government misconduct
    occurred in the defendant's case."    Id.   Application of this
    conclusive presumption in a particular case meant that a
    defendant's evidentiary burden to establish each element of the
    first prong of the Ferrara-Scott framework was satisfied.     Id.
    at 353-354.   We emphasized in Scott that this special
    evidentiary rule is unique in that it is "a remedy dictated by
    the particular circumstances surrounding Dookhan's misconduct as
    a chemist at the Hinton drug lab and is intended to apply only
    to this narrow class of cases in which a defendant seeks to
    withdraw his or her guilty plea after having learned of
    Dookhan's misconduct."   Id.   Further, we stated that "[s]hould
    the Ferrara analysis be applied in the case of a motion for a
    new trial under Mass. R. Crim. P. 30 (b) that does not arise
    from the investigation of Dookhan, the defendant will have the
    burden to establish each element of the first prong of Ferrara,
    and the adequacy of the defendant's showing will be committed to
    the sound discretion of the motion judge" (emphasis added).        Id.
    at 354.
    a.    Prong one of the Ferrara-Scott analysis:   egregious
    misconduct by the government in the defendant's case.     In the
    present appeal, the defendant contends that Farak's misconduct
    18
    at the Amherst drug lab was egregious, and that Farak was a
    government agent such that her misconduct is attributable to the
    Commonwealth.   Moreover, in the defendant's view, Farak's
    misconduct was systemic in magnitude.   As a consequence, the
    defendant argues, he was entitled to the conclusive presumption
    articulated in Scott, 467 Mass. at 352-353, and, therefore, he
    was not required to prove that such misconduct occurred in his
    own case.   The defendant asserts that even if this court does
    not apply the conclusive presumption, it still should determine
    that, because there was direct and circumstantial evidence
    suggesting that Farak's misconduct antedated the entry of his
    guilty pleas, misconduct must have occurred in his case.     Given
    all of these circumstances, the defendant contends that the
    discovery of Farak's egregious misconduct after he had tendered
    his guilty pleas rendered those pleas unknowing, unintelligent,
    and involuntary.   As such, the defendant continues, the judge
    abused his discretion in denying the defendant's motion to
    withdraw his guilty pleas.12   We agree with the defendant that
    12
    In Scott, the defendant argued that "relief [might] be
    available to him under Brady v. Maryland, 
    373 U.S. 83
    , 87
    (1963), as a result of the prosecution's failure to disclose the
    potentially exculpatory evidence of Dookhan's misconduct to the
    defendant prior to his guilty plea." Scott, 467 Mass. at 346
    n.5. In the present case, the defendant has not raised such an
    argument, presumably because evidence of misconduct by Farak had
    not yet come to light at the time the defendant pleaded guilty
    on April 13, 2009. As such, there was nothing for the
    Commonwealth to disclose.
    19
    Farak's misconduct was egregious and that it is attributable to
    the Commonwealth.   However, based on the evidence of her
    misconduct that has been uncovered thus far, we disagree with
    the defendant that he is entitled to the conclusive presumption
    articulated in Scott, or, alternatively, that he has shown that
    Farak's malfeasance antedated the entry of his guilty pleas.
    Nonetheless, given the absence of a thorough investigation into
    the matter by the Commonwealth, and the cloud that overshadows
    the integrity of drug analyses performed by Farak at the Amherst
    drug lab, we conclude that the defendant is entitled to a
    measure of relief, as will be described.    We turn to the
    Ferrara-Scott framework.
    i.   Egregious misconduct.    On January 6, 2014, Farak
    pleaded guilty to, among other offenses, four counts of
    tampering with evidence at the Amherst drug lab and four counts
    of stealing cocaine from that facility.    There is no dispute
    between the parties that this constituted "egregious misconduct"
    by Farak.   She was entrusted with analyzing purported drug
    samples, signing drug certificates that identified and set forth
    the precise weight of each sample, and testifying to the results
    of her analyses.    By tampering with evidence, Farak cast serious
    doubt on the integrity of this entire process.    Her misconduct
    could render a defendant's guilty plea involuntary by wholly
    undermining the evidentiary foundation of the Commonwealth's
    20
    case.   We conclude that Farak's misconduct constitutes the type
    of egregious misconduct that satisfies the first element of the
    first prong of the Ferrara-Scott analysis.     See Scott, 467 Mass.
    at 347-348.   See also Ferrara, 
    456 F.3d at 290-293
    .
    ii.     By the government.   The defendant contends that
    because Farak was a government agent, her misconduct is
    attributable to the Commonwealth.    In contrast, the Commonwealth
    argues that Farak's misconduct, while egregious, was an
    individual unlawful scheme and, as such, should not be
    attributable to the Commonwealth.    We agree with the defendant's
    position.
    In Scott, 467 Mass. at 348-350, we considered various
    circumstances where actions by a range of government agents
    might constitute misconduct "by the government" that could
    render a defendant's guilty plea involuntary.    See, e.g., United
    States v. Fisher, 
    711 F.3d 460
    , 467 (4th Cir. 2013) (law
    enforcement officer's conduct in lying in search warrant
    affidavit in defendant's case, regardless of prosecutor's lack
    of actual knowledge of officer's wrongdoing, constituted
    impermissible government conduct).    In the related context of a
    prosecutor's duty to disclose exculpatory evidence to the
    defense, we pointed out that, generally speaking, "the
    prosecutor's duty does not extend beyond information held by
    'agents of the prosecution team,'" Scott, supra at 349, quoting
    21
    Commonwealth v. Thomas, 
    451 Mass. 451
    , 454 (2008), but that
    "individuals other than prosecutors and police may be considered
    agents of the prosecution team."   Scott, supra.    See
    Commonwealth v. Martin, 
    427 Mass. 816
    , 824 (1998) (prosecutor's
    duty to disclose exculpatory evidence extends to information in
    possession of chemist at State police crime laboratory who "has
    participated in the investigation or evaluation of the case and
    has reported to the prosecutor's office concerning the case");
    Commonwealth v. Woodward, 
    427 Mass. 659
    , 679 (1998) (medical
    examiner considered to be agent of Commonwealth).    We concluded
    in Scott that Dookhan, in her role as a chemist at the Hinton
    drug lab, was an agent of the Commonwealth whose misconduct was
    attributable to the government for the limited purposes of the
    Ferrara analysis.   Scott, 467 Mass. at 349-350.    Significantly,
    it appeared from the record that Dookhan had engaged in
    egregious misconduct "to further what she perceived to be the
    mission of the Commonwealth" -- getting criminals off the
    streets -- and not to further her own "individual unlawful
    scheme."   Id. at 350, quoting Commonwealth v. Waters, 
    410 Mass. 224
    , 230 (1991).    Contrast Commonwealth v. Campiti, 
    41 Mass. App. Ct. 43
    , 65-66 (1996) (defendant not entitled to new trial
    where State police officer involved in investigation of
    defendant embezzled money from district attorney's office to
    22
    support gambling habit, but where such activity did not taint
    voluminous evidence against defendant).
    Farak, like Dookhan, was an agent of the prosecution team,
    given that, where she was the analyst for a purported drug
    sample recovered from a defendant, she "participated in the
    investigation or evaluation of the case" and "reported to the
    prosecutor's office concerning the case."     Scott, supra at 349,
    quoting Martin, 427 Mass. at 824.   In addition, Farak was
    "expected to testify as [an] expert witness[] regarding the
    testing of samples in various criminal prosecutions."     Scott,
    supra at 350.   Admittedly, it appears from the record that Farak
    was tampering with evidence at the Amherst drug lab in order to
    support her own cocaine habit.   Nonetheless, the effect of her
    misconduct was to raise serious questions about the integrity of
    her work on behalf of the Commonwealth.     With respect to at
    least eight known cases, it seems apparent that Farak's actions
    tainted the drug analysis process which, in turn, raises
    concerns about the reliability of her analyses in other cases
    where she was the assistant analyst.   Such malfeasance goes
    right to the heart of the Commonwealth's ability to convict a
    defendant in a drug case and, therefore, is directly related to
    "the Commonwealth's interest in law enforcement."     Waters, 
    410 Mass. at 230
    .   Farak's misconduct was not merely an "individual
    unlawful scheme," 
    id.,
     and, as such, is attributable to the
    23
    Commonwealth.   The defendant has satisfied the second element of
    the first prong of the Ferrara-Scott analysis.   See Scott, 467
    Mass. at 348-350.   See also Ferrara, 
    456 F.3d at 290-293
    .
    iii.   In the defendant's case.   Finally, the third element
    of the first prong of the Ferrara-Scott analysis requires the
    defendant to show that egregious misconduct by Farak antedated
    the entry of his guilty pleas and occurred in his own case.    See
    Scott, supra at 350-354.   See also Ferrara, 
    supra at 290
    .    The
    defendant asserts that he was entitled to the conclusive
    presumption articulated in Scott, supra at 352-353, and,
    therefore, he was not required to prove that Farak's misconduct
    occurred in his case.   Further, the defendant continues, even if
    this court does not apply the conclusive presumption, it still
    should determine that, because there was both direct and
    circumstantial evidence suggesting that Farak's misconduct
    antedated the entry of his guilty pleas, misconduct must have
    occurred in his case.   We conclude that the evidence on which
    the defendant relies is not sufficient, at this juncture, to
    establish either that Farak's misconduct constituted a systemic
    problem warranting application of the conclusive presumption, or
    that her misconduct antedated the entry of the defendant's
    guilty pleas.
    In Scott, we determined that "furnishing a drug certificate
    signed by Dookhan as a primary or secondary chemist in the
    24
    defendant's case [was] sufficient to establish the requisite
    nexus between the defendant's case and Dookhan's misconduct."
    Scott, 467 Mass. at 354.    Our bases for establishing a
    conclusive presumption that "egregious government misconduct
    occurred in the defendant's case" were our reasonable certainty
    that Dookhan's misconduct "touched a great number of cases," and
    that it was a "lapse of systemic magnitude in the criminal
    justice system" that "belie[d] reconstruction."    Id. at 352.   In
    the present case, no such reasonable certainty exists.
    Unlike the circumstances in Scott where the State police
    detective unit of the Attorney General's office conducted a
    broad formal investigation into Dookhan and her practices at the
    Hinton drug lab, see Scott, 467 Mass. at 339, the Commonwealth's
    investigation into the timing and scope of Farak's misconduct
    has been cursory at best.    Nonetheless, based on the record
    before us, only eight cases thus far have surfaced in which it
    appears that Farak tampered with evidence at the Amherst drug
    lab, beginning perhaps in the summer of 201213 and continuing
    13
    The motion judge was not persuaded that it was reasonable
    to infer from Farak's possession of the newspaper articles that
    were printed in the fall of 2011, see note 7, supra, that she
    was stealing controlled substances at that time. We conclude
    that the judge did not abuse his discretion in making this
    determination.
    25
    until January, 2013.14   It goes without saying that eight cases
    are eight cases too many.    However, the scope of Farak's
    misconduct does not appear to be, at this point in time,
    comparable to the enormity of Dookhan's misconduct at the Hinton
    drug lab.    Among other wrongdoing, Dookhan admitted to "dry
    labbing," contaminating drug samples (including converting
    negative samples into positive samples), removing drug samples
    from the lab's evidence locker in violation of protocol, failing
    to verify the proper functioning of lab equipment, and
    falsifying reports to hide her misconduct.    See Scott, supra at
    339-341.    In addition, Dookhan "acknowledged to investigators
    that she [might] not be able to identify those cases in which
    she tested the samples properly and those in which she did not,"
    id. at 339, rendering it virtually impossible to ascertain the
    full extent of Dookhan's misconduct during her tenure at the
    Hinton drug lab, which spanned approximately ten years.      There
    is no indication on the record before us that Farak's misconduct
    presents a comparable situation.    Therefore, the defendant is
    not entitled to the benefit of the conclusive presumption
    articulated in Scott, supra at 352-353, that egregious
    misconduct by Farak occurred in his case.
    14
    As far as we can tell, Farak has not provided any details
    concerning the timing and scope of her misconduct, apart from
    pleading guilty to the ten indictments.
    26
    That said, the systemic nature of Dookhan's misconduct only
    came to light following a thorough investigation of the Hinton
    drug lab by the State police detective unit of the Attorney
    General's office.    See Scott, 467 Mass. at 339-341.   As far as
    we are able to discern, no such investigation of the Amherst
    drug lab has occurred.    In another case decided today concerning
    Farak's misconduct at that facility, Commonwealth v. Ware,
    ante      ,      (2015), we stated that "the Commonwealth ha[s] a
    duty to conduct a thorough investigation to determine the nature
    and extent of [Farak's] misconduct, and its effect both on
    pending cases and on cases in which defendants already had been
    convicted of crimes involving controlled substances that Farak
    had analyzed."    The Commonwealth's obligation to conduct an
    investigation is premised on a prosecutor's "duty to learn of
    and disclose to a defendant any exculpatory evidence that is
    'held by agents of the prosecution team,'" who include chemists
    working in State drug laboratories.     Id., quoting Commonwealth
    v. Beal, 
    429 Mass. 530
    , 532 (1999).    It is incumbent on the
    Commonwealth to perform this duty in a timely fashion.    The
    burden of ascertaining whether Farak's misconduct at the Amherst
    drug lab has created a problem of systemic proportions is not
    one that should be shouldered by defendants in drug cases.      See
    generally Scott, supra at 353.     At the same time, given what we
    know, we have no basis for concluding in the present case that
    27
    Farak's misconduct is a "lapse of systemic magnitude in the
    criminal justice system."    Id. at 352.
    In a related vein, when considering the nexus between the
    government misconduct and the defendant's case, we agree with
    the motion judge that, although there is compelling evidence
    that Farak was stealing cocaine and replacing it with
    counterfeit substances, the defendant has not shown that Farak's
    misconduct antedated the entry of his guilty pleas and,
    therefore, must have occurred in his case.    Farak analyzed the
    drugs in the defendant's case on June 8, 2007.    The defendant
    pleaded guilty to trafficking in cocaine (fourteen to twenty-
    eight grams) and unlawful possession of ammunition on April 13,
    2009.   Farak was arrested on January 19, 2013, for misconduct
    that was alleged to have occurred the previous day.    The judge
    stated that powerful circumstantial evidence suggested that this
    was not the first time that Farak had tampered with drug samples
    at the Amherst drug lab.    The judge pointed out that the
    retesting of a small number of drug samples that originally had
    been analyzed by Farak indicated that she was tampering with
    evidence during the summer of 2012.    Moreover, during the fall
    of 2012, Farak's coworkers began to observe a change in her
    behavior, including frequent unexplained absences from her work
    station and a decrease in productivity.    From these facts and
    all of the physical evidence seized in connection with the
    28
    criminal investigation of Farak, the judge concluded that
    Farak's misconduct postdated the defendant's guilty pleas by
    almost three years.
    The defendant contends that the judge abused his discretion
    by not considering "strong circumstantial evidence of
    malfeasance" by Farak dating back to the start of her tenure as
    an analyst, suggesting a prolonged period of wrongdoing.      The
    defendant posits that Farak must have engaged in misconduct
    while she was working at the Hinton drug lab from the summer of
    2003 until the summer of 2004, see note 1, supra, because her
    high volume of drug testing rivaled that of Dookhan, who
    admitted to "dry labbing."   The defendant has offered no
    supporting evidence to substantiate this claim, and, in our
    view, it is wholly speculative.   With respect to Farak's work at
    the Amherst drug lab, her supervisor testified at the
    evidentiary hearing, see note 5, supra, that Farak's
    productivity was comparable to that of her colleague in the lab.
    The defendant also claims that there was evidence that Farak
    used cocaine in 2000.   Even if that were true, it does not
    support an inference that Farak must have been tampering with
    evidence in the Amherst drug lab prior to April 13, 2009.      We
    conclude that the judge did not abuse his discretion in
    determining that the defendant failed to show that egregious
    29
    misconduct by Farak antedated the entry of his guilty pleas and,
    therefore, must have occurred in his case.15
    Based on the Ferrara-Scott framework for reviewing a
    defendant's motion to withdraw his guilty pleas, the defendant
    here has not satisfied his burden of establishing each element
    of the first prong of the analysis.   That said, it is clear from
    the record that Farak engaged in egregious misconduct at the
    Amherst drug lab, and that any deficiencies in the evidence as
    15
    The defendant also directs our attention to other
    purported evidence of likely tampering that, in his view,
    demonstrates that Farak was engaged in misconduct at the Amherst
    drug lab long before the summer of 2012. In the so-called Finch
    and Espinosa cases, a Springfield police detective on March 17,
    2012, submitted suspected Oxycodone pills to the Amherst drug
    lab for testing, but, after analysis, Farak concluded that the
    pills did not contain any controlled substances. In
    Commonwealth vs. Berube, Hampden Super. Ct., No. 2011-00355
    (Oct. 30, 2013), a Springfield police officer testified that not
    all of the controlled substances presented at the trial were in
    the same condition as when the officer had seized them. Farak
    analyzed the substances in that case on May 12, 2011.
    Similarly, in Commonwealth vs. Carter, Hampden Super. Ct., No.
    2010-00115 (Nov. 15, 2013), the evidence presented at the trial
    (whitish pills) appeared to be different from the evidence that
    was seized by the police (blue pills). Farak analyzed the
    substances in that case on December 17, 2009. Finally,
    photocopies of three newspaper articles about individuals who
    had been investigated, charged, or sentenced for the illegal
    possession or theft of controlled substances had been printed
    from a computer in the fall of 2011 and were found in Farak's
    vehicle. See note 7, supra. Farak tested the substances in the
    defendant's case on June 8, 2007. Given that the defendant
    pleaded guilty on April 13, 2009, and that all of this purported
    evidence relates to activities that occurred thereafter, it does
    not support the defendant's contention that Farak's misconduct
    antedated the entry of his guilty pleas, which is the relevant
    inquiry under the Ferrara-Scott framework. See Scott, 467 Mass.
    at 350-354. See also Ferrara, 
    456 F.3d at 290
    .
    30
    to the scope and timing of her misconduct are attributable to
    the Commonwealth in light of its failure to conduct a thorough
    investigation of the matter.   Therefore, "it is incumbent upon
    us to exercise our superintendence power to fashion a workable
    approach" for giving defendants whose evidence samples were
    analyzed by Farak at the Amherst drug lab an opportunity to
    discover whether, in fact, their cases were affected by her
    misconduct.   Scott, 467 Mass. at 352.   Clearly, the scope of
    Farak's misconduct was wider than the ten charges to which she
    pleaded guilty, given that at least four additional cases have
    surfaced in which it appears that she tampered with evidence,
    but with respect to which no charges were filed.
    In the absence of a thorough investigation by the
    Commonwealth into Farak's misconduct, we conclude that the
    following procedures should be implemented.   In cases where a
    defendant seeks to vacate a guilty plea under Mass. R. Crim. P.
    30 (b) as a result of the revelation of Farak's misconduct at
    the Amherst drug lab, where the defendant proffers a drug
    certificate from the defendant's case signed by Farak on the
    line labeled "Assistant Analyst," and where the drug samples
    have not yet been destroyed, the defendant is entitled to retest
    those samples.   Drug samples that are part of a defendant's case
    are "tangible objects" subject to mandatory discovery under
    Mass. R. Crim. P. 14 (a) (1) (A) (vii), as amended, 
    442 Mass. 31
    1518 (2004).    See Commonwealth v. Williams, 
    456 Mass. 857
    , 870-
    871 (2010) ("The Commonwealth's responsibility to provide
    discovery to the defendant extends to material in its
    possession, custody, or control, and includes information in the
    possession of persons who have participated in the investigation
    or evaluation of the case and who report to the prosecutor's
    office concerning the case").    Cf. Commonwealth v. Mitchell, 
    444 Mass. 786
    , 795 (2005) (defendant has "unquestioned right, under
    the Sixth Amendment to the United States Constitution and art.
    12 of the Massachusetts Declaration of Rights, to obtain
    relevant evidence that bears on the question of his guilt or
    innocence or which otherwise will help his defense").    By such
    retesting, a defendant can ascertain definitively whether Farak
    tampered with the drug samples that were used to convict,
    thereby establishing the requisite "nexus between the government
    misconduct and the defendant's own case."16   Scott, 467 Mass. at
    351.
    More problematic are those cases, like the present one,
    where a defendant seeks to vacate a guilty plea under rule
    30 (b) as a result of the revelation of Farak's misconduct, but
    the defendant's drug samples have been destroyed.    See note 9,
    16
    General Laws c. 94C, § 47A, requires the Commonwealth to
    obtain a court order each and every time it wishes to destroy
    narcotics evidence. Trial judges should be very cautious in
    allowing motions to destroy such evidence where the narcotics
    have been analyzed at the Amherst drug lab.
    32
    
    supra.
       It is imperative that the Commonwealth thoroughly
    investigate the timing and scope of Farak's misconduct at the
    Amherst drug lab in order to remove the cloud that has been cast
    over the integrity of the work performed at that facility, which
    has serious implications for the entire criminal justice system.
    Within one month of the issuance of this opinion, the
    Commonwealth shall notify the judge below whether it intends to
    undertake such an investigation.   If so, the investigation shall
    begin promptly and shall be completed in an expeditious manner.
    As just stated, in our view, a thorough and timely
    investigation would be the appropriate course to follow in the
    circumstances.   In the absence of such an investigation,
    however, and where an individual defendant's drug samples have
    been destroyed, the judge, among other options, may entertain
    discovery motions to retest randomly selected drug samples that
    were tested by Farak and are still in existence in an effort to
    determine whether evidence of tampering can be identified and to
    establish the time frame of Farak's misconduct.   The results of
    the Commonwealth's investigation, or the evidence that can be
    gleaned from retesting, will dictate how the judge shall
    proceed, and we leave that matter to the judge's discretion.
    We reiterate that under the first prong of the Ferrara-
    Scott analysis, a defendant must show egregious misconduct by
    the government that preceded the entry of the defendant's guilty
    33
    pleas, and occurred in the defendant's case.    See Scott, 467
    Mass. at 347-354.    See also Ferrara, 
    456 F.3d at 290
    .   In the
    absence of evidence suggesting a problem of systemic magnitude
    at the Amherst drug lab, but nonetheless indicating a serious
    problem of undefined proportions, we afford the defendant here,
    and others in a similar position, the opportunity to show,
    through the retesting of drug samples, that Farak's misconduct
    preceded the entry of his guilty pleas and occurred in his own
    case.    Satisfaction of the first prong of the Ferrara-Scott
    analysis is not, however, the end of the judge's inquiry
    regarding whether to allow the defendant's motion to withdraw
    his guilty pleas under Mass. R. Crim. P. 30 (b).     We turn now to
    the second prong of the Ferrara-Scott analysis.
    b.    Prong two of the Ferrara-Scott analysis:    material
    influence on the defendant's decision to plead guilty.     The
    defendant contends that the judge erred in determining that,
    even if Farak's misconduct had antedated the defendant's guilty
    pleas, he still would have entered into the plea agreement.      In
    the defendant's view, the judge wholly minimized the scope of
    Farak's misconduct and, as a consequence, improperly assessed
    its impact on the defendant's decision whether to plead guilty
    or go to trial.     The Commonwealth acknowledges that the judge
    denied the defendant's motion to withdraw his guilty pleas in
    significant part because there was no evidence that the drug
    34
    analyses in the defendant's case were inaccurate, or that Farak
    was involved in misconduct at the time the defendant pleaded
    guilty.   Notwithstanding evidence of misconduct by Farak, the
    Commonwealth contends that there were good reasons for the
    defendant to accept the plea agreement, including the strength
    of the Commonwealth's case (including the defendant's own
    incriminating statements), and the significant concessions made
    by the Commonwealth regarding the charges and defendant's
    sentence.
    In Scott, 467 Mass. at 354, this court pointed out that
    satisfaction of the first prong of the Ferrara analysis did not
    "relieve the defendant of his burden under the second Ferrara
    prong to particularize Dookhan's misconduct to his decision to
    tender a guilty plea."   See Commonwealth v. Chatman, 
    466 Mass. 327
    , 333 (2013) ("The defendant has the burden of proving facts
    upon which he relies in support of his motion for a new trial");
    Commonwealth v. Lewin, 
    405 Mass. 566
    , 584-585 (1989) (charges
    against defendant need not be dismissed where police misconduct
    was egregious but not prejudicial to fair trial).   The same
    principle is applicable here with respect to Farak's misconduct.
    "[E]vidence of the circumstances surrounding [a] defendant's
    decision to tender a guilty plea should be well within the
    defendant's reach."   Scott, supra at 354 n.11.   Accordingly,
    under the second prong of the Ferrara-Scott framework, "the
    35
    defendant must demonstrate a reasonable probability that he
    would not have pleaded guilty had he known of [Farak's]
    misconduct."    Scott, supra at 354-355.    See Ferrara, 
    456 F.3d at 290, 294
    .    This court identified in Scott a number of factors
    that might be relevant to a defendant's showing under this
    second prong of analysis.    See Scott, supra at 355-356.    We
    emphasized in that case that "the full context of the
    defendant's decision to enter a plea agreement will dictate the
    assessment of his claim that knowledge of Dookhan's misconduct
    would have influenced the defendant's decision to plead guilty."
    Id. at 357.    See Ferrara, 
    supra at 294
    .   Here, the same analysis
    is applicable.
    We recognize that the motion judge considered whether the
    defendant would have pleaded guilty even if Farak's misconduct
    had antedated his guilty pleas.    However, the judge did so
    without the benefit of our opinion in Scott, and without our
    assessment of the potential implications of the Commonwealth's
    cursory investigation of Farak's misconduct at the Amherst drug
    lab.    In significant part, the judge determined that Farak's
    misconduct would not have materially influenced the defendant's
    decision to plead guilty because there was no evidence that the
    drug analyses in the defendant's case were inaccurate, or that
    Farak was tampering with evidence at the time the defendant
    tendered his guilty pleas.    Given the absence of a thorough
    36
    investigation by the Commonwealth into Farak's misconduct, we
    cannot ascertain whether the foundation for the judge's
    resolution of this issue is solid.     Therefore, following his
    resolution of the first prong of the Ferrara-Scott analysis, the
    judge should reconsider the second prong of that analysis "to
    determine whether, in the totality of the circumstances, the
    defendant can demonstrate a reasonable probability that had he
    known of [Farak's] misconduct, he would not have [pleaded
    guilty] and would have insisted on taking his chances at trial."
    Scott, 467 Mass. at 358.
    c.   Subpoena to establish scope and timing of Farak's
    misconduct.    In an effort to develop the facts necessary to
    establish the timing and scope of Farak's misconduct, the
    defendant subpoenaed Farak's spouse, Nikki Lee, to testify at
    the evidentiary hearing.     See note 5, supra.   The defendant
    wanted to show that Farak had a history of cocaine use dating
    back to 2000, and he sought to question Lee about Farak's drug
    use before and during her employment at the Amherst drug lab.
    Lee's testimony, in the defendant's view, would be highly
    probative of when Farak became motivated to tamper with
    evidence.     In response, Lee filed a notice of her intent to
    invoke her privilege against self-incrimination under the Fifth
    Amendment to the United States Constitution and art. 12 of the
    Massachusetts Declaration of Rights, as well as spousal
    37
    privilege under G. L. c. 233, § 20, Second.17   Construing Lee's
    notice of her intent to invoke certain privileges as a motion to
    quash the subpoena, the judge allowed the motion on the basis of
    spousal privilege.
    On appeal, the defendant contends that the judge erred in
    quashing the subpoena because the evidentiary hearing was not a
    criminal proceeding against Farak and, therefore, the spousal
    privilege was inapplicable.   The propriety of asserting a
    testimonial privilege is a matter of statutory interpretation,
    presenting a pure question of law that is subject to de novo
    review.   See Matter of a Grand Jury Subpoena, 
    447 Mass. 88
    , 90
    (2006).   See also Bridgewater State Univ. Found. v. Assessors of
    Bridgewater, 
    463 Mass. 154
    , 156 (2012).   Based on our review, we
    agree with the defendant that the spousal privilege was not
    applicable in the circumstances of this case.   However, we
    affirm the judge's decision on other grounds.   See Commonwealth
    17
    In her notice of intent to invoke certain privileges,
    Nikki Lee also asked that she be excused from testifying at the
    evidentiary hearing because, among other reasons, her sworn
    testimony before the State grand jury investigating Farak's
    misconduct at the Amherst drug lab already had been provided to
    the defendant. Lee testified before the grand jury that she had
    tried cocaine, and that she had observed Farak using cocaine in
    2000, although not since that time. We note that the spousal
    privilege set forth in G. L. c. 233, § 20, Second, cannot be
    invoked in proceedings before a grand jury. See Matter of a
    Grand Jury Subpoena, 
    447 Mass. 88
    , 99 (2006). A spouse who
    testifies before a grand jury will not be deemed to have waived
    the spousal privilege at a later proceeding because "if there is
    no privilege not to testify before a grand jury, then no
    privilege has been waived by giving such testimony." Id. at 98.
    38
    v. Va Meng Joe, 
    425 Mass. 99
    , 102 (1997) ("An appellate court is
    free to affirm a ruling on grounds different from those relied
    on by the motion judge if the correct or preferred basis for
    affirmance is supported by the record and the findings").
    General Laws c. 233, § 20, Second, provides (with certain
    exceptions not relevant here):    "[N]either husband nor wife
    shall be compelled to testify in the trial of an indictment,
    complaint or other criminal proceeding against the other."       See
    Mass. G. Evid. § 504(a) (2014).     "The purpose of the spousal
    privilege is to protect the relationship of marriage from the
    potential harm of one spouse giving adverse testimony against
    the other."     Commonwealth v. Szerlong, 
    457 Mass. 858
    , 869
    (2010), cert. denied, 
    131 S. Ct. 1494
     (2011).    See Matter of a
    Grand Jury Subpoena, 447 Mass. at 96.     Because "[t]estimonial
    privileges 'are exceptions to the general duty imposed on all
    people to testify,'" they "must be strictly construed."        Three
    Juveniles v. Commonwealth, 
    390 Mass. 357
    , 359 (1983), cert.
    denied sub nom. Keefe v. Massachusetts, 
    465 U.S. 1068
     (1984),
    quoting Commonwealth v. Corsetti, 
    387 Mass. 1
    , 5 (1982).       See
    Matter of a Grand Jury Subpoena, supra at 90.
    When considering the meaning of a testimonial privilege,
    "we look first and foremost to the language of the statute as a
    whole."   Id.   Generally speaking, the spousal privilege applies
    to testimony that would be given by one spouse in a criminal
    39
    trial against the other spouse.18    See id. at 90-93.   Here, Lee
    would not be testifying at a criminal trial against Farak.
    Rather, the defendant sought her testimony at an evidentiary
    hearing pertaining to postconviction motions filed by fifteen
    defendants who claimed that alleged criminal conduct by Farak
    rendered their guilty pleas to various drug charges unknowing,
    unintelligent, and involuntary.     See note 5, supra.   Lee's
    testimony at such a proceeding cannot be barred by invocation of
    the spousal privilege under G. L. c. 233, § 20, Second.
    Accordingly, the judge erred in quashing the defendant's
    subpoena on this basis.
    That said, based on our review of the record, the judge
    properly could have quashed the defendant's subpoena on the
    basis of Lee's invocation of her privilege against self-
    incrimination.19   "The proscription of the Fifth Amendment that
    18
    In Matter of a Grand Jury Subpoena, 447 Mass. at 99, this
    court did not decide "whether, or to what extent, the spousal
    privilege may be invoked in pretrial (or posttrial)
    proceedings." Given that the evidentiary hearing at issue in
    the present case was not a pretrial proceeding against Farak, we
    do not consider the scope of the spousal privilege beyond the
    plain language of the statute, which resolves the matter at
    hand.
    19
    Lee's testimony before the grand jury did not constitute
    a waiver of her privilege against self-incrimination with regard
    to the evidentiary hearing. "The waiver [of a testimonial
    privilege], once made, waives the privilege only with respect to
    the same proceeding; the witness may once again invoke the
    privilege in any subsequent proceeding." Commonwealth v. King,
    
    436 Mass. 252
    , 258 n.6 (2002). See generally Commonwealth v.
    40
    '[n]o person . . . shall be compelled in any criminal case to be
    a witness against himself' may be invoked whenever a witness
    reasonably believes that the testimony could be used in a
    criminal prosecution or could lead to other evidence that might
    be so used."   Pixley v. Commonwealth, 
    453 Mass. 827
    , 832 (2009),
    citing Kastigar v. United States, 
    406 U.S. 441
    , 444-445 (1972).
    See Commonwealth v. Baker, 
    348 Mass. 60
    , 62-63 (1964).   Because
    the privilege against self-incrimination is a "fundamental
    principle" of our judicial system, it "is to be construed
    liberally in favor of" the person claiming it.   Commonwealth v.
    Borans, 
    388 Mass. 453
    , 455 (1983).   "A witness may refuse to
    testify unless it is 'perfectly clear, from a careful
    consideration of all the circumstances in the case, that the
    witness is mistaken, and that the answer[s] cannot possibly have
    such tendency' to incriminate (emphasis in original)."
    Commonwealth v. Funches, 
    379 Mass. 283
    , 289 (1979), quoting
    Hoffman v. United States, 
    341 U.S. 479
    , 488 (1951).
    By subpoenaing Lee, the defendant sought to elicit
    testimony at the evidentiary hearing regarding Farak's cocaine
    use before and during her employment at the Amherst drug lab.
    During her testimony before the grand jury, Lee stated that she
    herself had tried cocaine, that she had observed Farak using
    Martin, 
    423 Mass. 496
    , 500-501 (1996) (discussing so-called
    "waiver by testimony" rule).
    41
    cocaine in 2000, and that she had marijuana in her house when
    police officers arrived to search the premises as part of their
    investigation of Farak.20   To the extent that Lee testified about
    her own drug possession in relation to that of Farak, it is not
    "perfectly clear" that such testimony could not possibly have
    the tendency to incriminate Lee and subject her to criminal
    prosecution.   Therefore, Lee's invocation of her privilege
    against self-incrimination would have been a proper basis for
    the judge to quash the defendant's subpoena.
    5.   Conclusion.   The order denying the defendant's motion
    to withdraw his guilty pleas pursuant to Mass. R. Crim. P.
    30 (b) is vacated, and we remand this case for further
    proceedings in accordance with this opinion.
    So ordered.
    20
    The enactment of G. L. c. 94C, § 32L, inserted by St.
    2008, c. 387, § 2, decriminalized only the possession of one
    ounce or less of marijuana. A defendant still may be criminally
    charged with possession of more than one ounce of marijuana.
    See G. L. c. 94C, § 32L, third par.; Commonwealth v. Jackson,
    
    464 Mass. 758
    , 762 (2013). Similarly, a defendant may be
    criminally charged with possession with intent to distribute
    marijuana, in violation of G. L. c. 94C, § 32C (a), even where
    the amount of marijuana possessed is one ounce or less. See
    Commonwealth v. Keefner, 
    461 Mass. 507
    , 508 (2012).