Commonwealth v. Chukwuezi , 475 Mass. 597 ( 2016 )


Menu:
  • NOTICE: All slip opinions and orders are subject to formal
    revision and are superseded by the advance sheets and bound
    volumes of the Official Reports. If you find a typographical
    error or other formal error, please notify the Reporter of
    Decisions, Supreme Judicial Court, John Adams Courthouse, 1
    Pemberton Square, Suite 2500, Boston, MA, 02108-1750; (617) 557-
    1030; SJCReporter@sjc.state.ma.us
    SJC-11579
    COMMONWEALTH    vs.   XZENIYEJU CHUKWUEZI.
    Suffolk.      February 12, 2016. - September 29, 2016.
    Present:     Gants, C.J., Spina, Botsford, Duffly, & Lenk, JJ.1
    Homicide. Firearms. Evidence, Computer simulation, Prior
    consistent statement, Alibi. Alibi. Constitutional Law,
    Sentence. Practice, Criminal, Instructions to jury,
    Argument by prosecutor, Sentence, Capital case.
    Indictments found and returned in the Superior Court
    Department on July 1, 2009.
    The cases were tried before Linda E. Giles, J.
    Stephen Paul Maidman for the defendant.
    Zachary Hillman, Assistant District Attorney, for the
    Commonwealth.
    LENK, J.       The defendant was convicted by a Superior Court
    jury of murder in the first degree on a theory of deliberate
    premeditation, and of unlawful possession of a firearm, in
    1
    Justices Spina and Duffly participated in the deliberation
    on this case prior to their retirements.
    2
    connection with the 2009 shooting death of Soheil Turner, a
    fifteen year old boy.   The defendant was eighteen years old at
    the time of the shooting.   On appeal, the defendant argues that
    the trial judge abused her discretion in excluding from evidence
    a computer-generated simulation that was intended to assist the
    jury in determining the shooter's height.      He also asserts error
    in several other respects, described in greater detail below,
    and seeks relief under G. L. c. 278, § 33E.     Having reviewed the
    entire record, we affirm the convictions and discern no reason
    to exercise our authority to grant extraordinary relief.
    1.   Background and procedural posture.    We recite the facts
    the jury could have found, reserving certain details for later
    discussion.   At approximately 7:20 A.M. on May 7, 2009, Turner
    was shot in the back of the head and in the right shoulder while
    waiting for a school bus in the Roxbury section of Boston.      He
    died later that day as a result of the shooting.     Police
    recovered two shell casings from the scene of the shooting that
    appeared to have been fired from a semiautomatic firearm.
    Several video surveillance cameras recorded the shooting
    and the surrounding circumstances.2   Shortly after 7 A.M. on the
    morning of the shooting, the shooter, an African-American male
    2
    Police obtained video recordings from three surveillance
    cameras in the vicinity of the shooting. None of the recordings
    was of sufficient quality to allow for identification of the
    shooter.
    3
    carrying a yellow umbrella, walked north on Adams Street from
    the direction of Forest Street, and stopped at the northeast
    corner of Dudley Street and Adams Street.    The shooter was
    wearing a black hooded sweatshirt with the hood up, and a loose
    fitting T-shirt and pants.   A few minutes later, a young woman,
    later identified as Amari Figueroa, arrived at the southeast
    corner of the intersection, talking on her cellular telephone.
    She and the shooter waved to each other.    Shortly thereafter,
    Turner arrived in the area and went into a convenience store on
    Dudley Street near the southwest corner of the intersection.
    After Turner returned outside, the shooter walked diagonally
    across the intersection towards him, and stood with him in front
    of the store.   The two had a short conversation.   The shooter
    then drew a gun that he had been concealing and shot Turner
    twice.   The shooter ran around the corner onto Adams Street,
    tucking the gun into his waist area as he did so, then ran up
    the east side of Adams Street and out of view.
    Figueroa eventually told police that the person she had
    waved to on the morning of the shooting was the defendant.      She
    had known the defendant for several years, socialized with him
    occasionally, and lived two houses away from him on Forest
    Street, a short walk from the intersection where the shooting
    took place.   After hearing the gunshots, Figueroa saw the
    defendant "speed walking" down Adams Street in the direction of
    4
    Forest Street.3    She then telephoned 911.    At some point in the
    weeks after the shooting, Figueroa met with the defendant and
    asked him why he shot Turner.    The defendant told her that a
    fifteen year old recently had shot and injured one of his
    friends.    The defendant explained that "[i]f he didn't kill
    [Turner] then he was going to be next."       The defendant also
    urged her not to say anything to police.
    Other witnesses corroborated Figueroa's testimony about the
    shooting.   Raymona Hartepps walked out of the convenience store
    shortly before the shooting, and overheard part of the shooter's
    brief conversation with Turner.    She recalled hearing Turner ask
    the defendant where he was from and what his name was.4      As soon
    as Hartepps had walked past the store, she heard two gunshots,
    and saw the shooter run around the corner onto Adams Street in
    the direction of Forest Street, tucking a black object into his
    right pocket.     Isaiah Grant also saw the shooter run down Adams
    Street onto Forest Street.     Grant further observed the shooter
    run up a set of steps and around to the right side of a duplex
    house on Forest Street.    The defendant, who was in high school
    3
    Forest Street is at the southern end of Adams Street, and
    perpendicular to it.
    4
    The shooter identified himself as either "Jonathan from
    Wayne Wood" or "Robert from Norwood."
    5
    at the time, lived with his family on the right side of that
    house.
    On July 1, 2009, a grand jury returned two indictments,
    charging the defendant with murder in the first degree, G. L.
    c. 265, § 1, and unlawful possession of a firearm, G. L. c. 269,
    § 10 (a).   The defendant's theory of the case was one of
    mistaken identity.     He sought to impeach Figueroa's credibility
    on cross-examination, and called alibi witnesses.     The
    defendant's mother and younger brother both testified that the
    defendant was at home getting ready for school at the time of
    the shooting.     The defendant also testified in his own defense,
    stating that he did not shoot Turner.    In addition, the
    defendant sought unsuccessfully to introduce a computer-
    generated simulation in evidence.
    On October 19, 2010, the jury found the defendant guilty of
    murder in the first degree on a theory of deliberate
    premeditation.5    They also found him guilty of unlawful
    possession of a firearm.     The defendant was sentenced to life in
    prison without the possibility of parole for the conviction of
    murder in the first degree, and to a term of from four to five
    5
    The jury were instructed with respect to murder in the
    first degree both on the theory of deliberate premeditation and
    on the theory of extreme atrocity or cruelty. They also were
    instructed on murder in the second degree.
    6
    years of incarceration for the conviction of unlawful possession
    of a firearm, to run concurrently.   This appeal followed.
    2.   Discussion.   The defendant argues that the judge erred
    with respect to several evidentiary rulings:    excluding the
    computer-generated simulation from evidence; admitting testimony
    that the Commonwealth offered as a prior consistent statement by
    Figueroa; and allowing the Commonwealth to impeach an alibi
    witness for not volunteering his knowledge about the defendant's
    whereabouts to police, without providing appropriate
    instructions on alibi to the jury.   The defendant further argues
    that the Commonwealth improperly invoked sympathy for the
    victim's family during its closing argument.    Moreover, the
    defendant contends that he should not have been sentenced to
    life in prison without the possibility of parole because he was
    only eighteen at the time of the shooting.     The defendant also
    seeks relief under G. L. c. 278, § 33E.6
    6
    In addition, the defendant asserts error in the judge's
    decision to permit Figueroa, over objection, to enter the court
    room through a side door in the presence of the jury, rather
    than via the main door used by other witnesses. The defendant
    asserts that that decision violated his constitutional rights to
    due process and a fair trial because it intimated to the jury
    that he was "a bad and dangerous person whose guilt [could] be
    virtually assumed." See Commonwealth v. Brown, 
    364 Mass. 471
    ,
    475 (1973). That argument is without merit, because there is no
    evidence in the record that the jury would have understood a
    witness's method of entry into the court room to be related to
    the defendant's dangerousness, thereby creating an unacceptable
    risk of prejudice against him. See 
    id. at 476
     (burden is on
    7
    a.   Computer-generated simulation.   Whether the shooter was
    the same height as the defendant was a matter of dispute at
    trial.7   To aid the jury in making that determination, the
    defendant commissioned a computer-generated simulation of the
    crime scene, based on two photographs from the surveillance
    camera closest to the shooting,8 in which the shooter was
    standing relatively upright on a level surface.9
    defendant to show judge's decision in imposing security measure
    was "arbitrary or unreasonable").
    7
    Immediately after the shooting, Figueroa told police that
    the shooter was six feet, one inch tall, while other witnesses
    stated that he was five feet, nine inches tall. The defendant's
    height around the time of the shooting was not measured, but
    police estimated that he was between five feet, eleven inches
    and six feet tall. Photographs taken at the time of the
    defendant's arrest similarly indicate that he was approximately
    six feet tall.
    8
    The video recording comprised a series of time-lapsed
    photographs.
    9
    An engineer identified fixed points in the background of
    the photographs, and visited the crime scene in person to
    measure their locations relative to each other and to the
    camera. A graphic designer then used those measurements and
    computer software to create a three-dimensional virtual model of
    the crime scene.
    Although the judge did not make an explicit finding that
    the camera continued to be positioned in the same place and at
    the same angle at the time the measurements were taken as at the
    time of the shooting, we infer this fact from testimony at the
    voir dire hearing that the camera was "locked down" and "mounted
    to a wall," from photographs of the camera's location that were
    admitted in evidence, and from the Commonwealth's decision to
    point out the location of the camera during a view of the crime
    scene.
    8
    Using principles of photogrammetry,10 the simulation
    superimposed human-shaped figures of increasing height over the
    shooter as he appeared in the photographs.   The figures were to
    scale with the photographs, and were shown standing rigidly
    upright, wearing hooded sweatshirts with the hoods up.     They
    increased in height in one inch increments from five feet, nine
    inches to six feet, as measured from the soles of their feet to
    the tops of their hoods.   In effect, the simulation attempted to
    facilitate a comparison between actual height of the figures and
    the shooter's apparent height in the photographs.   The
    Commonwealth filed a motion in limine to exclude it from
    evidence on the ground that it was misleading.
    i.   Voir dire.   The judge conducted a voir dire hearing at
    which she questioned the graphic designer who produced the
    simulation, an engineer, and a forensic photographer who worked
    for the Federal Bureau of Investigation (FBI).   The graphic
    designer described in detail how he had produced the simulation.
    At the judge's request, he used the simulation to estimate that
    the shooter was between five feet, nine inches and five feet,
    10
    "Photogrammetry is the process of obtaining information,
    usually measurements, from images" (citation omitted). Edmond,
    Cole, Cunliffe, & Roberts, Admissibility Compared: The
    Reception of Incriminating Expert Evidence (i.e., Forensic
    Science) in Four Adversarial Jurisdictions, 3 U. Denv. Crim. L.
    Rev. 31, 50 n.156 (2013).
    9
    ten inches tall -- several inches shorter than the defendant, by
    most accounts.11
    The engineer testified that he was familiar with two
    techniques for assessing a suspect's height from a video
    recording.    The first technique was the one the graphic designer
    had used.    The second technique, which the judge referred to as
    a "height analysis," involved directly measuring the suspect's
    height from the video recording, and could take the suspect's
    posture into account.    This second technique, however, required
    using high-quality video footage from multiple camera angles;
    such footage was not available.    The forensic photographer who
    worked for the FBI described a third technique that similarly
    could account for a suspect's posture.12   In the forensic
    photographer's opinion, the defendant's simulation was
    misleading because it compared rigid figures with a person of
    normal posture.
    In light of this testimony and her own viewing of the
    simulation, the judge concluded that the simulation was
    "hopelessly misleading."    She noted that the jury generally
    11
    See footnote 7, supra.
    12
    The third technique involved placing a person whose
    height was known next to a ruler in roughly the same place as
    the suspect was standing at the time of the crime. By using the
    same camera that recorded the crime to recreate the scene, the
    technique allowed forensic investigators to take a suspect's
    posture into account in estimating his or her height.
    10
    should be allowed to consider simulation evidence "in a close
    case," and suggested that a "height analysis" in accordance with
    one of the other techniques described might have been
    admissible.   Nonetheless, she expressed concern that the
    simulation would confuse the jury into thinking that the
    shooter, who was not standing as rigidly upright as the
    computer-generated figures, was shorter than he actually was.
    She declined to allow its admission in evidence, over the
    defendant's objection.
    ii.   Review for abuse of discretion.     The defendant argues
    that the judge's evidentiary ruling deprived him of a meaningful
    opportunity to present a complete defense, a right guaranteed by
    the Sixth Amendment to the United States Constitution and
    art. 12 of the Massachusetts Declaration of Rights.     See Pixley
    v. Commonwealth, 
    453 Mass. 827
    , 834 (2009).    That right,
    however, is not unfettered; it is subject to the limitations set
    forth under standard rules of evidence.   See Montana v.
    Egelhoff, 
    518 U.S. 37
    , 42 (1996), and cases cited.     In
    determining whether to admit a computer-generated simulation
    like the one at issue here, a trial judge must determine whether
    the simulation is relevant evidence; whether the simulation's
    conditions correspond to those of the original incident, see
    Commonwealth v. Corliss, 
    470 Mass. 443
    , 456 (2015); and whether
    the evidence will confuse or mislead the jury.     See Commonwealth
    11
    v. Rosa, 
    422 Mass. 18
    , 25 (1996); Lally v. Volkswagen
    Aktiengesellschaft, 
    45 Mass. App. Ct. 317
    , 332 (1998).
    Although "[w]e have consistently held that lower court
    findings based on documentary evidence available to an appellate
    court are not entitled to deference," Commonwealth v. Novo, 
    442 Mass. 262
    , 266 (2004), S.C., 
    449 Mass. 84
     (2007), the judge's
    decision in this case was based both on her viewing of the
    simulation itself and on witnesses' explanations of the
    simulation during the voir dire hearing.   We therefore review
    the judge's decision to exclude the simulation for abuse of
    discretion.   See Commonwealth v. McGee, 
    469 Mass. 1
    , 9 (2014).13
    The defendant argues that the judge did not understand that
    the figures were created precisely to scale based on principles
    of photogrammetry, and could be presented with any desired
    height or posture.   In his view, the Commonwealth would have had
    the opportunity to emphasize on cross-examination and during its
    closing argument that the figures were standing rigidly upright
    13
    But see Commonwealth v. Scott, 
    470 Mass. 320
    , 327 (2014)
    (reviewing judge's decision to exclude third-party culprit
    evidence "independently" and under "a standard higher than that
    of abuse of discretion" because of "[the] constitutional
    dimension" of exclusion of such evidence [citations omitted]).
    Because the defendant sought to use the simulation to call into
    question whether he was the same height as the shooter, and not
    to identify specifically another person as the culprit, the
    higher standard does not apply in this case. See Commonwealth
    v. Silva-Santiago, 
    453 Mass. 782
    , 800-801 (2009) (defining
    third-party culprit evidence).
    12
    while the shooter was not, so there was no danger that the jury
    would be misled or confused.    The defendant further argues that
    the simulation should have been admitted because it was highly
    relevant to the identity of the shooter, a "central issue in the
    case."    See Commonwealth v. Jaime, 
    433 Mass. 575
    , 579 (2001).
    Accordingly, he contends that the judge abused her discretion in
    excluding the simulation.
    We do not agree.    In Commonwealth v. Corliss, supra at 456,
    in considering a simulation produced by the graphic designer who
    was involved in this case, we determined that it was an
    appropriate exercise of judicial discretion to exclude that
    simulation from evidence.    We deferred to the trial judge's
    finding that the defendant had not proved satisfactorily that
    the simulation's conditions matched those of the incident being
    simulated.14   Id.   Similarly here, we cannot say the judge made
    "a clear error of judgment in weighing the factors relevant to
    the decision, . . . such that the decision [fell] outside the
    range of reasonable alternatives" (quotations and citations
    14
    There   was evidence in that case suggesting that the
    surveillance   camera that had recorded the incident had been
    moved during   a renovation after the incident, and that the level
    of the floor   also had been changed. See Commonwealth v.
    Corliss, 
    470 Mass. 443
    , 455 (2015).
    13
    omitted).     See L.L. v. Commonwealth, 
    470 Mass. 169
    , 185 n.27
    (2014), and cases cited.15
    The judge's determination was not, as the defendant
    contends, based on a misunderstanding of the principles of
    photogrammetry.    Rather, the judge concluded reasonably that the
    simulation could not be explained with sufficient clarity to
    avoid confusing the jury, and did not take into account
    important factors that would have affected the shooter's
    apparent height.     By the judge's own account, it took her
    "almost an hour . . . to figure [out] what [the graphic
    designer] [was] saying."     Furthermore, it is evident that the
    "height analysis by comparison" that the simulation facilitated
    was inexact at best.     The photographs used in the simulation
    showed the shooter wearing loose-fitting clothing and a hood
    that obscured his posture and the location of the top of his
    head.     In one of the photographs, the shooter appeared to be
    mid-stride.    In the other, the shooter may have been hunched or
    leaning forward under his umbrella.     In both, the shooter was
    addressing a victim who was only five feet, four inches tall,
    and thus was likely to be tilting his head downward.     In light
    15
    Cf. Commonwealth v. Caruso, 
    85 Mass. App. Ct. 24
    , 32-33
    (2014) (judge declined to admit simulation created by graphic
    designer as newly discovered evidence, and questioned
    simulation's ability accurately to establish suspect's height).
    14
    of these concerns, the judge did not abuse her discretion in
    excluding the simulation.
    Moreover, even if the exclusion had constituted error, it
    would not have been prejudicial.     See Commonwealth v. Corliss,
    supra at 456-457.   While the defendant's height around the time
    of the shooting was not measured, most estimates placed him
    between five feet, eleven inches and six feet tall.       The jury
    also may have been able to assess for themselves the defendant's
    height at the time of trial.16    Eyewitnesses placed the shooter's
    height within a narrow range, from five feet, nine inches tall
    to six feet, one inch tall.     In addition, one of the
    surveillance videos showed Hartepps, who was five feet, nine
    inches tall, walk past the shooter, allowing the jury to compare
    their apparent heights.     In his closing argument, defense
    counsel discussed at length the possible difference between the
    defendant's height and the shooter's.    Given that the
    Commonwealth would have explored the limitations of a "height
    analysis by comparison" on cross-examination, the simulation was
    unlikely to have supplemented the other evidence of the
    shooter's height in any meaningful way.     Cf. Commonwealth v.
    Perito, 
    417 Mass. 674
    , 684 (1994) (judge did not abuse
    16
    The record does not indicate whether the defendant, then
    a teenager, grew in height between May 7, 2009, and his trial in
    October, 2010.
    15
    discretion in concluding that failure to produce low-quality
    video recording of suspect's height and build did not prejudice
    defendant where same information was available from eyewitness).
    b.   Prior consistent statement.   Although she had had
    several earlier opportunities to do so, Figueroa did not tell
    police that the defendant was the shooter until they interviewed
    her on May 19, 2009.17   At trial, Figueroa explained that she
    initially declined to identify the defendant because she was
    concerned for her safety.   During cross-examination, however,
    the defendant elicited testimony that police had told Figueroa
    during an interview on May 8, 2009, that they thought she knew
    more about the shooting than she had disclosed; that police told
    Figueroa during that interview that they would require her to
    testify before the grand jury, where lying would constitute
    perjury; and that by May 8, 2009, Figueroa believed that people
    in the community were aware that she had seen the shooting.      The
    Commonwealth then introduced, over objection, testimony from
    Figueroa's mother that Figueroa had confided in her on the night
    of May 7, 2009, that "[s]omeone had got shot and she knew who
    17
    When interviewed at the scene immediately after the
    shooting on May 7, 2009, and at the police station later that
    day, Figueroa told police that she did not recognize the
    shooter. During an interview on the evening of May 8, 2009,
    however, Figueroa learned that police believed she had waved to
    the shooter shortly before the shooting. When police asked her
    at that interview whether she knew who the shooter was, she
    responded that she wanted to "pass the question."
    16
    did it," and that the shooter lived "[t]wo houses down" from
    them.     The defendant argues that Figueroa's mother's testimony
    should not have been admitted.
    "A witness's prior statement that is consistent with that
    witness's trial testimony is usually inadmissible" (citation
    omitted).    Commonwealth v. Novo, 
    449 Mass. 84
    , 93 (2007).   If,
    however, a judge
    "makes a preliminary finding that there is a claim that the
    witness's in-court testimony is the result of recent
    contrivance or a bias, and the prior consistent statement
    was made before the witness had a motive to fabricate or
    the occurrence of the event indicating a bias, the evidence
    may be admitted for the limited purpose of rebutting the
    claim of recent contrivance or bias."
    Mass. G. Evid. § 613(b)(2) (2015).    See Mass. G. Evid. § 613
    note, at 215, citing Commonwealth v. Novo, 449 Mass. at 93.
    Here, the judge found that the defendant had claimed that
    Figueroa's identification of him as the shooter was the result
    of recent contrivance or bias, because the defendant had
    suggested on cross-examination that Figueroa felt pressure from
    both police and the community falsely to identify a specific
    individual as the shooter.18    The defendant does not contest that
    18
    The jury were not instructed regarding the proper use of
    the prior consistent statement. Because the defendant did not
    request such an instruction, however, there was no substantial
    likelihood of a miscarriage of justice. See Commonwealth v.
    Rivera, 
    430 Mass. 91
    , 100 (1999) ("While the defendant was
    entitled, on request, to a limiting instruction, there is no
    17
    finding.     Nonetheless, he argues that Figueroa's motive to
    fabricate already existed before she told her mother, on the
    night of May 7, 2009, that the shooter was their neighbor,
    because she would have felt pressure from the community to
    identify someone immediately after the shooting earlier that
    day.
    Police did not mention the possibility of criminal
    prosecution for perjury, however, until May 8, 2009, the day
    after Figueroa confided in her mother.     Thus, the mother's
    testimony properly was admitted as a prior consistent statement
    to counter the defendant's suggestion of police pressure.        See
    Commonwealth v. Andrews, 
    403 Mass. 441
    , 455 (1988); Commonwealth
    v. Mayfield, 
    398 Mass. 615
    , 629-630 (1986).      Given this
    conclusion, we need not consider when Figueroa's other supposed
    motive to fabricate, pressure from the community, first arose.
    c.   Alibi witness.   The defendant called his younger
    brother, Cjaillon Andrade, to testify as an alibi witness that
    he had seen the defendant at home getting ready for school at
    the time of the shooting.     Over objection, the Commonwealth
    impeached Andrade's testimony on cross-examination on the ground
    that Andrade had not reported this alibi to police.      The
    defendant argues that the judge should not have allowed this
    substantial likelihood of a miscarriage of justice because the
    judge did not give such an instruction sua sponte").
    18
    impeachment.    In addition, the defendant argues that the jury
    instructions regarding alibi witness testimony were incorrect.
    Because "[a] person ordinarily has no legal obligation to
    provide exculpatory information to the police," Commonwealth v.
    Hart, 
    455 Mass. 230
    , 238 (2009), the Commonwealth may impeach a
    witness for failing to provide such information only if it
    establishes a sufficient foundation.   We previously have
    required the Commonwealth to establish "[1] that the witness
    knew of the pending charges in sufficient detail to realize that
    he possessed exculpatory information, [2] that the witness had
    reason to make the information available, [and] [3] that he was
    familiar with the means of reporting it to the proper
    authorities."   Commonwealth v. DaSilva, 
    471 Mass. 71
    , 82 (2015),
    quoting Commonwealth v. Hart, supra.    The defendant concedes
    that the Commonwealth established each of these facts, but
    argues that the judge additionally should have considered that
    police were aware that Andrade might have relevant information,
    yet never contacted him.19   In the defendant's view, this
    additional consideration would have led the judge to conclude
    that the impeachment of Andrade was unfairly prejudicial.
    19
    Police knew from speaking with the defendant's mother
    that Andrade had been at home with her on the morning of the
    shooting.
    19
    In Commonwealth v. Hart, supra, we noted that there are
    some circumstances "in which it would not be natural for a
    witness to provide the police before trial with exculpatory
    information," including when the witness "thinks that [his or]
    her information will not affect the decision to prosecute."    It
    is possible that Andrade assumed as much; he was still a
    teenager at the time the defendant was accused, and testified
    that he believed police "probably" had spoken with his mother
    when they executed a search warrant, providing them with the
    same alibi that was the subject of his testimony.   Nonetheless,
    the defendant had an opportunity to rehabilitate the
    Commonwealth's efforts at impeachment by eliciting this
    information from Andrade on redirect, and did so effectively.
    No more was required to protect against the possibility of
    prejudice.   See id. at 242 ("If the impeachment evidence is
    admitted, the defendant is free to elicit on redirect
    examination the witness's reason for prior silence").
    The defendant's arguments regarding jury instructions
    pertaining to alibi witnesses similarly are without basis.     He
    argues that the judge should have sustained his objection to the
    judge's instruction that, in considering the credibility of a
    given witness, the jury could consider "whether or not he or she
    has any interest in the outcome of the case."   Although the
    contested instruction might have been problematic if it had
    20
    targeted specifically the credibility of only the defendant's
    alibi witnesses, it was included within a long list of standard
    factors that the jury could consider in assessing any witness's
    credibility.   Because "[t]he charge was a general comment,
    stated an obvious point, and did so only once," it was not
    error.    See Commonwealth v. Roderick, 
    411 Mass. 817
    , 821 (1992).
    It also was not error for the judge to deny the defendant's
    request for an instruction that the Commonwealth had the burden
    of disproving the defendant's alibi.    "[J]udges are not required
    to deliver their instructions in any particular form of words,
    so long as all necessary instructions are given in adequate
    words."   Commonwealth v. Sinnott, 
    399 Mass. 863
    , 878 (1987).
    Here, the judge instructed the jury "that the Commonwealth has
    the burden of proving beyond a reasonable doubt that the
    Defendant committed the offense as charged," which included
    "proving that the Defendant was present at the scene and not
    somewhere else at the time."    She added, "[I]f you have a
    reasonable doubt about whether the defendant was present at the
    time and place of the offenses, or about any other element of
    the crimes, then you must find him not guilty."   These
    instructions conformed with the model instruction on alibi then
    in effect, see Instruction 9.120 of the Criminal Model Jury
    Instructions for Use in the District Court (2009), and
    21
    adequately described the burden the defendant sought to
    emphasize in his requested instruction.
    The defendant also argues, for the first time on appeal,
    that the jury should have been instructed that a person has no
    obligation to provide exculpatory information to police.       See
    Commonwealth v. Hart, supra at 238.   Recognizing that
    "[o]rdinarily judges are not required, sua sponte, to instruct
    juries as to the purposes for which evidence is offered at
    trial," Commonwealth v. Roberts, 
    378 Mass. 116
    , 126 (1979),
    S.C., 
    423 Mass. 17
     (1996), we discern no error in the absence of
    such an instruction.
    d.   Closing argument.   The defendant contends that the
    Commonwealth improperly invoked the jury's sympathy during
    closing argument.   Over objection, the Commonwealth described
    the victim's family as being "summoned to the hospital that
    morning after he was shot, forced to bear witness to the
    [carnage] that this man [inflicted] on his body."    The judge
    declined to give a requested curative instruction.    In the
    defendant's view, the Commonwealth's closing placed too much
    emphasis on the suffering of the victim's family, and deprived
    him of his Federal and State constitutional rights to due
    process and a fair trial.
    A prosecutor "should not play on the sympathy or emotions
    of the jury," but is entitled to "tell the jury something of the
    22
    person whose life [has] been lost in order to humanize the
    proceedings" (citations omitted).    Commonwealth v. Rodriguez,
    
    437 Mass. 554
    , 566 (2002).    Although the Commonwealth's
    reference to the "carnage" witnessed by the victim's family
    likely invoked some sympathy, it was presented as part of a
    broader, humanizing description of the victim's life.20     In
    context, the statement was not the "focal point" of the
    Commonwealth's argument, and was not excessive.   See id. at 567.
    In any event, the jury were instructed to "confine [their]
    deliberations to the evidence and nothing but the evidence," to
    "determine the facts based solely on a fair consideration of the
    evidence," and "not to be swayed by prejudice or sympathy."
    These instructions helped to ensure that any sympathy the jury
    felt for the victim's family did not influence their decision.
    20
    The prosecutor stated in full,
    "Soheil Turner was a son, a grandson, a nephew and a
    friend to many people. Because of the actions of this
    Defendant he is none of those things anymore.
    "Forever fifteen years old, the lasting image of his
    short life will be standing innocently, defenseless and
    unaware. A school kid waiting at his bus stop and eating
    his honey bun. Unaware that his executioner was waiting
    across the street and watching. Unaware that in moments
    his life was going to end on the morning of May 7th of 2009
    as he waited for his school bus.
    "His family summoned to the hospital that morning
    after he was shot, forced to bear witness to the [carnage]
    that this man [inflicted] on his body."
    23
    Cf. Commonwealth v. Camacho, 
    472 Mass. 587
    , 608-609 (2015)
    (context of summation, evidence at trial, and jury instructions
    prevented improper closing from creating substantial likelihood
    of miscarriage of justice).
    e.   Sentence of life without the possibility of parole.
    The defendant received the statutorily required sentence of life
    in prison without the possibility of parole for his conviction
    of murder in the first degree.   See G. L. c. 265, § 2, as
    amended by St. 2014, c. 189, § 5 (providing parole eligibility
    for person convicted of murder in first degree only if person
    was younger than eighteen at time of offense).   The defendant
    argues that this sentence is unconstitutionally disproportionate
    to his crime because he was only eighteen years old at the time
    of the shooting.21   The age of eighteen, however, "is the point
    where society draws the line for many purposes between childhood
    and adulthood."   Roper v. Simmons, 
    543 U.S. 551
    , 574 (2005).
    21
    The defendant also argues that his sentence violates his
    rights to equal protection under both the United States
    Constitution and the Massachusetts Declaration of Rights,
    because of his age at the time of the shooting. That argument
    is without basis, as there is a rational basis for making
    determinations of parole eligibility based on age, and age is
    not a suspect classification requiring heightened scrutiny. See
    Commonwealth v. Weston W., 
    455 Mass. 24
    , 30 (2009). See also
    Commonwealth v. Freeman, 
    472 Mass. 503
    , 508 (2015) ("We have
    repeatedly said that those who challenge the constitutionality
    of a statute that does not burden a suspect group or a
    fundamental interest carry a heavy burden in seeking to overcome
    the statute's presumption of constitutionality" [quotations and
    citations omitted]).
    24
    That such line-drawing may be subject "to the objections always
    raised against categorical rules," 
    id.,
     does not itself make the
    defendant's sentence unconstitutional.
    f.   Relief pursuant to G. L. c. 278, § 33E.   We have
    examined the record carefully pursuant to our duty under G. L.
    c. 278, § 33E,22 and discern no basis on which to grant the
    defendant extraordinary relief.
    Judgments affirmed.
    22
    We note that, during cross-examination by the defendant,
    one of the detectives who executed a search warrant to search
    the defendant's house testified that a rifle was seized from the
    house. That testimony was not relevant to the charges before
    the jury, and had the potential to lead them to believe that the
    defendant had a propensity for violence or was affiliated with a
    gang. Nonetheless, the defendant elicited from the detective
    that there was no indication that the rifle "had anything to do
    with" him, and the judge properly instructed the jury that the
    charge of unlawful possession of a firearm referred only to a
    semiautomatic handgun, not a rifle. Thus, it did not create a
    substantial likelihood of a miscarriage of justice.