# State v. Harvey

> Supreme Court of New Jersey · July 30, 1997 · 151 N.J. 117

URL: https://www.frixlaw.com/law-library/cases/9643196

## Case

- **Full name:** State of New Jersey, Plaintiff-Respondent, v. Nathaniel Harvey, Defendant-Appellant
- **Court:** Supreme Court of New Jersey
- **Decided:** July 30, 1997
- **Citations:** 151 N.J. 117; 699 A.2d 596; 1997 N.J. LEXIS 261
- **Precedential status:** Published
- **Opinion:** Opinion of the court by Pollock
- **Judges:** Pollock, Handler
- **Cited by:** 248 later opinions in the Frix Law Library

## Citator (automated)

- No negative treatment found by the automated citator. That is not the same as a confirmation that the case is good law; read the citing cases.
- Full citator and citing cases: https://www.frixlaw.com/law-library/cases/9643196

## How later opinions describe it (automated extraction)

- finding that polymarker test (used for DNA analysis) was generally accepted in scientific community because independent tests validated its reliability, highly-regarded laboratories used test, scholarly and scientific publications approved test and other jurisdictions admitted…
- stating that an appellate court "reviewing a decision on the admission of scientific evidence . . . should scrutinize the record and independently review the relevant authorities, including judicial opinions and scientific literature"
- concluding that trial court’s curative instruction was sufficient to mitigate prejudice to defendant caused by reference to unindicted suspect’s polygraph results where instruction to disregard evidence was immediate
- concluding that trial court's curative instruction was sufficient because it was immediate and it specifically instructed jurors to disregard reference to unindicted suspect's polygraph results
- recognizing that an appellate court addressing a Daubert issue may “remand the matter to the trial court to take additional testimony about the general acceptance of the scientific evidence”

## Opinion text

The opinion of the Court was delivered by
POLLOCK, J.
Defendant, Nathaniel Harvey, appeals directly from a judgment of conviction and sentence of death for the purposeful-or-knowing murder of Irene Schnaps. A jury originally convicted defendant of Schnaps’s murder and sentenced him to death in October 1986. This Court reversed that conviction because of errors in the admission of defendant’s confession and in the failure of the trial court to give a “Gerald charge.” State v. Harvey, 121 N.J. 407 , 581 A.2d 483 (1990) (Harvey I), cert. denied, 499 U.S. 931 , 111 S.Ct. 1336 , 113 L.Ed.2d 268 (1991). The phrase “Gerald charge” refers to a charge that distinguishes murder when the defendant intended to kill from murder when the defendant intended only to cause serious bodily injury that resulted in death. State v. Gerald, 113 N.J. 40 , 549 A.2d 792 (1988). Neither error occurred in the second trial.
In the absence of defendant’s confession, the State relied substantially on DNA evidence to establish that defendant was Sehnaps’s killer. Again, a jury convicted defendant and imposed the death penalty. On this appeal, defendant raises numerous points, including challenges to the admission of the DNA evidence and to the jury charge. After careful review of all of defendant’s arguments, we affirm his conviction and death sentence.
- I -
A. Discovery of the Body and the Crime Scene
Schnaps, age thirty-seven, lived alone in a ground-floor apartment at the Hunter’s Glen complex in Plainsboro, New Jersey. *138 After she failed to appear at work on June 17, 1985, a concerned eoworker went to her apartment and entered through an unlocked doorway. On discovering Schnaps’s lifeless body, he immediately called for assistance.
Investigating police detected no signs of forced entry. The bedroom, however, was a scene of obvious struggle. Blood stains were on the carpet and throughout the room. Sehnaps’s naked body lay face-up on the floor. She had sustained severe head and facial wounds. Despite the extensive head wounds, no bloodstains were present on Sehnaps’s chest and stomach.
The matting of several small hairs to the victim’s body and the absence of blood on her torso suggested that someone had attempted to wipe the body clean. The carpeting around the body was wet from water. Schnaps’s back was covered with blood.
A white pillowcase bore a bloody sneaker-print with a chevron pattern and the letters “PON.” Although the bedding appeared clean, blood stained the mattress, the underlying box spring, a cardboard box that protruded from under the bed, and a towel.
The bedroom also included an empty Seiko-LaSalle watch box, an empty Olympus camera box, and an empty jewelry box. In the bathroom, the investigators found Schnaps’s poeketbook. The pocketbook was open and did not contain any money.
B. The Autopsy
On June 18, 1985, Dr. Marvin Shuster, the Middlesex County medical examiner, conducted an autopsy. He determined that Schnaps had sustained approximately fifteen blows to the head. The largest wound, six inches long and one inch wide, extended from the front of her forehead to the top of her head. In general, the skull wounds were either curving or linear. The curving wounds were likely caused by hammer blows, and the linear wounds could have been caused by an item akin to a tire iron, a two-by-four, or a dull hatchet or axe. Some of the blows fractured Schnaps’s skull and caused direct injury to the brain. Blows had *139 been delivered from both the right and left sides, some from the front, but most from behind.
Triangular pressure marks appeared on both sides of the neck. Some of the victim’s teeth were knocked out, and her jaw was broken. The right sides of the neck, jaw, cheek, and forehead were bruised, and she was cut behind one ear.
Unable to attribute death to any particular wound, Dr. Shuster concluded that the combination of the blows had killed Schnaps. Sehnaps had bled profusely and died within a matter of minutes.
C. The Apprehension and Interrogation of Nathaniel Harvey
1. October 28, 1985
Throughout the summer and autumn of 1985, West Windsor police looked for the perpetrator of a series of unsolved burglaries and sexual assaults. Based on eyewitness descriptions, they believed that the perpetrator was a stocky black male, under five-feet three-and-a-half inches tall, who usually travelled on foot or by bicycle. The police also believed that the perpetrator of those other crimes might be responsible for Schnaps’s murder. Defendant fit the physical description.
On October 28, 1985, police investigating three burglaries arrested defendant after he was sighted standing with his bicycle at the edge of a soybean field in West Windsor. One of the burglary victims identified defendant at a subsequent “show-up.”
During questioning by West Windsor police on October 28, defendant confessed to committing a number of burglaries in West Windsor, as well as a sexual assault. Defendant also agreed to accompany the police on a car tour to point out the locations of his crimes.
2. October 29, 1985
At 10:00 a.m. on the following morning, defendant accompanied two detectives on a car tour of West Windsor. At 1:15 p.m., defendant consented to a search of his car and his Jamesburg apartment for evidence related to an unrelated sexual assault. *140 Although defendant gave as his address his father’s apartment in Jamesburg, he lived with his estranged wife in West Windsor. Apparently, defendant feared that his wife would lose her welfare benefits if he revealed that he lived with her. After defendant signed the consent form, police transferred him to the Mercer County Detention Center.
While searching defendant’s car, the officers discovered two watches, including a Seiko-LaSalle like the one missing from Schnaps’s apartment. They notified the Plainsboro Police Department. After obtaining a search warrant, a Plainsboro officer seized the watch. The search of Harvey’s Jamesburg apartment did not yield any evidence.
3. October SO, 1985
Following defendant’s arraignment for the murder of Schnaps, investigating officers resumed questioning him. At one point, defendant said that “he would tell [them] about the murder but first wanted to speak to his father.” After defendant spoke with his father, police failed to administer new Miranda warnings. Shortly thereafter, defendant confessed to murdering Schnaps.
D. The First Trial
On November 19, 1985, a Middlesex County grand jury returned a three-count indictment charging defendant with the purposeful-or-knowing murder of Schnaps, contrary to N.J.S.A. 2C:11-3 (count one), second-degree robbery, contrary to N.J.S.A. 2C:15-1 (count two), and second-degree burglary, contrary to N.J.S.A. 2C:18-2 (count three). Two days later, on November 21, 1985, the Middlesex County Prosecutor filed a Notice of Aggravating Factors pursuant to Rule 3:13-4(a) and N.J.S.A. 2C:11-3c(2), making defendant’s case a capital prosecution. The State alleged the following aggravating factors:
1. The murder was outrageously or wantonly vile, horrible or inhuman in that it involved an aggravated battery to the victim
[N.J.S.A. 2C:11 — 3c(4)(c).]
*141 2. The murder was committed for the purpose of escaping detection, apprehension, trial, imprisonment or confinement for robbery and burglary committed by the defendant
[N.J.S.A. 2C:11 — 3c(4)(f).]
3. The murder was committed while the defendant was engaged in the commission of or an attempt to commit, or flight after committing robbery and burglary
[N.J.S.A. 2C:11-3c(4)(g).]
The prosecution relied heavily on defendant’s confession. Harvey I, supra, 121 N.J. at 415-17 , 581 A.2d 483 . The jury found defendant guilty of purposeful-or-knowing murder, first-degree robbery, second-degree burglary, and felony murder, for which he had not been indicted. At a penalty-phase hearing, the same jury found the presence of all three alleged aggravating factors and returned a sentence of death.
E. Harvey I
On direct appeal, this Court reversed defendant’s conviction and remanded for a new trial. The Court held that the trial court’s jury instructions on murder did not comport with Gerald, supra, 113 N.J. 40 , 549 A.2d 792 , which required that a jury must be instructed separately on the crimes of intentional murder and serious-bodily-injury murder (SBI minder). At the time of Harvey’s trial, a conviction for SBI murder did not render a defendant death-eligible. In his confession, Harvey claimed that the victim struck him and that he then struck her only once. Relying in part on statements in his confession, the Court concluded that the evidence provided a rational basis for a jury to have concluded that defendant intended only to injure Schnaps. Harvey I, supra, 121 N.J. at 413 , 581 A.2d 483 .
The Court further held that Harvey’s confession had been procured in violation of State v. Hartley, 103 N.J. 252 , 511 A.2d 80 (1986). Hartley provides that after invoking the right to silence, a defendant must receive new Miranda warnings before interrogation can resume. The Court ruled that, by asking to speak with his father, Harvey had invoked his right to silence. Harvey I, supra, 121 N.J. at 418-20 , 581 A.2d 483 . Consequently, the police *142 should have advised him again of his constitutional rights before resuming interrogation. The failure of the police to abide by that bright-line test rendered defendant’s confession inadmissible. Id. at 422, 581 A.2d 483 .
F. The Interim Between Trials
Faced with the prospect of retrying Harvey without his confession, the prosecution hired Cellmark Diagnostics Laboratory (Cell-mark) to conduct DNA tests on the blood recovered from the crime scene. Cellmark, the first commercial laboratory accredited by the American Society of Crime Laboratory Directors, conducts DNA tests exclusively. It analyzed a bloodstained section of Schnaps’s box spring, a bloodstained piece of cardboard, and a sample of both Schnaps’s and defendant’s blood.
G. The Retrial
Defendant’s retrial, from the pretrial motions to the return of the death sentence, lasted from November 25, 1992, to December 16, 1994. The trial court denied a motion for a new trial on January 30,1995.
1. Pretrial Motions
Following a hearing, the trial court denied defendant’s motion to suppress evidence seized from defendant’s car, ruling that defendant had consented to the search. The defendant also moved to exclude the State’s DNA evidence. After a three-day New Jersey Rule of Evidence 104 (Rule 104) hearing, the trial court denied defendant’s motion and held that the State’s DNA evidence was admissible.
2. Guilt Phase
After a lengthy jury-selection process, the guilt phase began on November 29,1994.
a. State’s Case
The State adduced evidence about the crime scene, including fifty-two photographs and various items of physical evidence. *143 Investigating officers testified to the discovery of the bloody sneaker print, the empty Seiko-LaSalle watch box, the empty jewelry box, and the empty Olympus camera box, all of which were admitted into evidence.
Philip Beesley, a forensic scientist employed by the New Jersey State Police, testified that blood work done on control samples from both the defendant and Schnaps revealed that Schnaps’s blood was type “one plus, one minus” for the genetic marker PGM, and type “1” for the enzyme CA II. Defendant was type “one plus, one plus” for PGM and type “2-1” for CA II. Beesley further revealed that bloodstains found on the box spring and on the piece of cardboard tested as “one plus, one plus” for PGM and type “2-1” for CA II. He concluded that those stains were consistent with Harvey’s blood, therefore, not Schnaps’s. Beesley also testified that CA II of phenotype 2-1 is found only in African Americans.
Dr. Marvin Shuster testified about the nature of the wounds suffered by Schnaps and the cause of her death. See supra part I.B. Theodore Mozer, a forensic scientist employed by the New Jersey State Police, testified that one of the hairs recovered from Schnaps’s back did not belong to her. Mozer testified that this hair had “Negroid” characteristics that were consistent with a control hair taken from Harvey.
Mozer also examined two pairs of sneakers seized from Harvey’s ex-wife’s West Windsor apartment and the size 6 1/2 “Pony” sneakers that Harvey was wearing when he was arrested. Aided by six enlarged photographs of the bloody footprint left at the crime scene, Mozer explained that Harvey’s “Pony” sneakers were consistent with the sneaker impression. Although Harvey’s sneakers “could” have left the bloody mark, Mozer could not conclude definitively that they had done so.
In support of the admission of the DNA evidence, the State presented two witnesses from Cellmark, Julie Cooper, a senior molecular biologist, and Dr. Charlotte Word, a microbiologist and supervisor of forensic casework. They testified generally that *144 DNA tests conducted on the blood samples recovered at the crime scene were genetically comparable to defendant’s DNA. Defendant’s genotypes for the genetic markers examined were common to only one-in-1,400 African Americans.
b. Defendant’s Case
Defendant did not testify.
His case consisted of only two witnesses. A witness from Seiko testified that it had made thousands of watches like the one seized from the trunk of defendant’s car. Dr. Robert Shaler, Director of Forensic Biology for the Office of the Chief Medical Examiner for the City of New York, testified that he believed that the DNA tests were “scientifically indefensible.” In the course of his testimony, he pointed out the imbalances in the dots on the strips. He found imbalances at the GYPA, HBGG, and GC loci. Dr. Shaler testified that at the GYPA locus an individual’s genes could cause a difference in dot intensity. He further disputed the one-in-1,400 calculation and asserted that he believed that the genetic makeup of the blood recovered from the crime scene could be found in approximately one in fifty to one in 200 African Americans.
c. The Verdict
In its jury instructions, the court included a Gerald charge. Consistent with State v. Purnell, 126 N.J. 518, 530-34 , 601 A.2d 175 (1992), the court also charged on the unindicted count of felony murder. After deliberating for three and one-half hours, the jury returned its verdict finding defendant guilty of purposeful-or-knowing murder, felony murder, first-degree robbery, and second-degree burglary.
3. Penalty Phase
a. State’s Case
The State relied exclusively on the evidence adduced at the guilt phase to support proof of three aggravating factors: the murder involved aggravated assault of the victim, N.J.S.A. 2C:11-3c(4)(c); the murder was committed to escape detection, N.J.S.A. 2C:11- *145 3e(4)(f); and the murder was committed during the course of a robbery and burglary, N.J.S.A. 2C:11-3c(4)(g).
b. Defendant’s Case
Pursuant to N.J.S.A. 2C:11-3c(5)(c) and (h), defendant alleged ten mitigating factors: the age of the defendant at the time of the murder; the defendant was traumatized at a young age when he witnessed the death of his older sister; defendant was uprooted from his home and sent to live with his grandparents who abused him; defendant suffered feelings of abandonment when his parents moved north and failed to send for him; he was exposed to domestic violence in the home of his grandparents; he was exposed to domestic violence in the home of his parents; he is a caring and loving father; his continuing relationship with his children including financial contributions; his relationship with his mentally disabled brother and his mentally disabled daughter; and all factors which relate to the defendant’s childhood and family background.
Professor Richard Moran, a criminologist specializing in the correlation between age and crime, testified that if defendant were sentenced to prison rather than death, he could not be eligible for parole prior to age 64, by which time he would be in the age group least likely to commit violent crime. Therefore, the chances of defendant committing another violent crime would be minute.
A forensic social worker testified about defendant’s social history. Defendant was raised in poverty. His often-absent father was a sharecropper and a migrant worker. As a two-year old, defendant had been injured in an automobile accident, but did not receive medical treatment. When defendant was four, he and his five-year old sister were left in an unheated home. While trying to light a stove, defendant’s sister spilled some kerosene on her nightgown. When defendant lit a match, she burned to death.
Defendant’s parents later moved to New Jersey, leaving defendant in the care of his grandparents for seven years. During his childhood, defendant was abused by both his grandfather and father.
*146 Various family members testified that defendant was a loving and earing father, who also comforted his developmentally-disabled brother. Defendant’s family asked the jury not to sentence defendant to death.
c. The Verdict
After deliberating for two and one-half hours, the jury returned a unanimous verdict that defendant had committed the murder for the purpose of avoiding apprehension, N.J.S.A. 2C:11-3c(4)(f), and in the course of a robbery and burglary, N.J.S.A. 2C:11-3c(4)(g). It did not find aggravating factor N.J.S.A. 2C:11-3c(4)(c), that the murder involved aggravated assault to the victim. The jury further found that the aggravating factors outweighed all of the mitigating factors and that each aggravating factor alone outweighed all of the mitigating factors. The trial court sentenced defendant to death.
Later, the trial court sentenced defendant as a persistent offender on the non-capital counts of first-degree robbery and second-degree burglary. Accordingly, defendant received a sentence of life with a twenty-five year parole bar on the first degree robbery conviction to run consecutively to defendant’s death sentence for capital murder. On the burglary conviction, defendant was sentenced to a concurrent term of five years in prison with a two-and-one-half year parole bar. Those sentences were made consecutive to prison terms previously imposed on defendant for unrelated crimes. Thus, defendant’s aggregate sentence, irrespective of the death penalty, is life plus sixty-five years with a fifty-seven-and-one-half year parole disqualifier.
- II -
We first consider defendant’s contention that the trial court committed reversible error when it failed to instruct the jury in accordance with this Court’s later decision in State v. Mejia, 141 N.J. 475 , 662 A.2d 308 (1995).
*147 - A-
Evaluation of defendant’s Mejia argument begins with Gerald, supra, 113 N.J. 40 , 549 A.2d 792 . In Gerald , this Court held as a matter of state constitutional law that only those murderers who intended to kill were eligible for the death penalty. Those who intended to inflict only serious bodily injury were not death-eligible under N.J.S.A. 2C:11—3(a)(1) or (2), even if their actions resulted in their victim’s death. Id. at 69-70 , 549 A.2d 792 . Subsequent constitutional and statutory amendments have abrogated the Gerald rule by subjecting to the death penalty murderers who intended to cause only serious bodily injury. N.J. Const. art. I, ¶ 12 (1992); L. 1993, c. 111 (signed May 5, 1993). At the time of Sehnaps’s murder, however, only those who murdered with the intent to kill were death-eligible. Thus, the Gerald rule applies to the present case.
Under Gerald , the jury’s determination whether defendant killed with the intent to kill or merely with the intent to inflict serious bodily injury, became the linchpin of capital-punishment eligibility. If the evidence produced at trial provided even a rational basis for a jury to convict a defendant of SBI murder rather than intentional murder, the trial court was compelled to “instruct the jury to specify which, if [either], of those findings forms the basis for conviction.” State v. Coyle, 119 N.J. 194, 209 , 574 A.2d 951 (1990). Under Gerald , the jury’s key role became to determine whether defendant’s intent was to kill or to inflict SBI. State v. Moore, 122 N.J. 420, 484 , 585 A.2d 864 (1991).
In Mejia, supra, 141 N.J. at 481 , 662 A.2d 308 , this Court clarified Gerald by stating that a jury need not be unanimous on whether the defendant intended to kill or to injure seriously. The intent-to-kill requirement is not an element of murder, but a “triggering device” for the death-penalty phase of the trial. Id. at 486, 662 A.2d 308 . Thus, unanimity is not required in making the Gerald determination. Id. at 487, 662 A.2d 308 (noting “unanimity requirement extends only to verdicts adverse to the defendant”). *148 A jury can return a valid guilty verdict for purposeful-or-knowing murder even if it cannot agree that defendant killed intentionally. Such a verdict, however, will not support the imposition of the death penalty. Id. at 486 , 662 A.2d 308 . In Mejia , the record provided “a rational basis for a jury to find that defendant intended only to cause serious bodily injury.” Id. at 481 , 662 A.2d 308 . The trial court’s failure to instruct the jury about the possibility of returning a non-unanimous verdict on the defendant’s intent thus constituted plain error.
In State v. Harris, 141 N.J. 525, 549 , 662 A.2d 333 (1995), however, we held that a failure to give a non-unanimous Mejia charge could be considered harmless when the evidence of intent to kill was overwhelming and no rational basis existed for concluding that defendant had intended to inflict only serious bodily injury.
Although defendant’s case was tried seven months before the issuance of Mejia and Harris , defense counsel requested a charge on a non-unanimous verdict. Before us, defendant argues that the absence of a non-unanimous verdict charge coerced the jury into returning a verdict of capital murder. The initial inquiry, then, is whether the evidence provided a rational basis to find that defendant intended to inflict only serious bodily, and not to kill.
- B -
Failure to charge in accordance with Gerald/Mejia requires the reversal of a death sentence if the record below contains evidence that is “minimally adequate to provide a rational basis for the jury to hold a reasonable doubt that the defendant intended to cause death.” Mejia, supra, 141 N.J. at 489, 662 A.2d 308 ; see also State v. Pennington, 119 N.J. 547, 561 , 575 A.2d 816 (1990) (characterizing rational-basis standard as a “low threshold”); State v. Pitts, 116 N.J. 580, 615 , 562 A.2d 1320 (1989) (same). Accordingly, a rational basis may exist even though a jury likely would reject the defendant’s serious-bodily-injury theo *149 ry. Mejia, supra, 141 N.J. at 489, 662 A.2d 308 ; see State v. Dixon, 125 N.J. 223, 254 , 593 A.2d 266 (1991) (“The error was not harmless because there was evidence in this case that could have sustained an SBI ... verdict. We do not suggest that such a verdict was likely, but merely that if the jury returned that verdict, the court could not reject it.”). Satisfaction of the “minimally adequate/rational basis” standard, however, requires more than a mere “scintilla of the evidence.” Mejia, supra, 141 N.J. at 489, 662 A.2d 308 ; State v. Crisantos, 102 N.J. 265, 278 , 508 A.2d 167 (1986).
We have found harmless error in eases where defendants’ actions have been “so wantonly brutal that the jury could have concluded only that the defendant intended to cause death.” Mejia, supra, 141 N.J. at 488, 662 A.2d 308 ; see, e.g., Harris, supra, 141 N.J. at 550, 662 A.2d 333 (victim was handcuffed and lying on ground when defendant shot him in back of head); State v. Bey, 129 N.J. 557, 579 , 610 A.2d 814 (1992) (Bey III) (defendant stomped on victim with sufficient force to crush her chest), cert. denied, 513 U.S. 1164 , 115 S.Ct. 1131 , 130 L.Ed.2d 1093 (1995); State v. Biegenwald, 126 N.J. 1, 18 , 594 A.2d 172 (1991) (Biegenwald IV) (defendant fired four gunshots into victim’s head); State v. McDougald, 120 N.J. 523, 558-60 , 577 A.2d 419 (1990) (defendant slashed victims’ throats, bludgeoned one with baseball bat, and expressed intent to kill both before and after killings); State v. Hightower, 120 N.J. 378, 412-14 , 577 A.2d 99 (1990) (Hightower I) (defendant shot victim at close range in chest, neck, and head, and then dragged victim into freezer); State v. Rose, 120 N.J. 61, 63-64 , 576 A.2d 235 (1990) (Rose II) (defendant fired twelve-gauge shotgun point-blank into victim’s stomach); State v. DiFrisco, 118 N.J. 253 , 571 A.2d 914 (1990) (DiFrisco I) (defendant shot victim four times in head and admitted intention to kill), cert. denied, — U.S. -, 116 S.Ct. 949 , 133 L.Ed.2d 873 (1996); Pitts, supra, 116 N.J. at 614-20 , 562 A.2d 1320 (defendant threatened to kill victims two days before murders, inflicted twenty-five to thirty stab wounds with combat knife, cut one victim’s throat twice, and paused to take victim’s pulse to verify death); State v. *150 Hunt, 115 N.J. 330, 374-77 , 558 A.2d 1259 (1989) (defendant stated intent to kill immediately prior to stabbing victim twenty-four times).
- C -
Schnaps was brutally murdered. Her killer struck her fifteen times in the head with a blunt instrument. He struck her with sufficient force and frequency to fracture her skull in several places, knock out her teeth, and break her jaw. He further applied sufficient pressure to her neck to cause severe bruising. Reviewing that medical evidence in Harvey I, supra, we wrote that “such repeated blows can support a jury finding of intentional murder.” 121 N.J. at 413 , 581 A.2d 483 .
Relying substantially on the assertions in defendant’s confession, however, we concluded that the evidence as a whole required reversal. We reached that conclusion because “the record provided a rational basis for the jury to find that [defendant] intended to cause only serious bodily injury.” Id. at 414 , 581 A.2d 483 (internal quotations omitted). Contrary to the dissent’s assertions, all of the “pertinent facts” contained in Harvey’s confession were not before the jury in the retrial. Post at 299, 699 A.2d at 686. Not before the jury was defendant’s confession that he had struck the victim only once in response to being punched in the nose. Harvey I, supra, 121 N.J. at 412 , 581 A.2d 483 . That confession provided a rational basis for a juror in the first trial to have concluded that Harvey intended only to injure his victim and not kill her. The absence of Harvey’s confession is a critical distinction between the record in Harvey I and that in the present case.
- D -
In determining whether a rational basis existed for a Gerald charge, we are confined to the evidence in the record. See Bey III, supra, 129 N.J. at 581 , 610 A.2d 814 (“[W]e examine scrupulously the evidence that was adduced at trial to see whether *151 the jury had a rational basis for finding that the defendant could have intended only serious bodily injury.”); Dixon, supra, 125 N.J. at 253 , 593 A.2d 266 (noting appellate role is to ask if jury answered question on death-eligibility). We may not consider the evidence in the first trial. In brief, defendant’s confession, which was admitted in the first trial but excluded from the second, is not part of the record.
Absent the confession, the evidence does not provide a rational basis for the supposition that defendant struck his victim to ward off her attack. The dissent attempts to distinguish Sehnaps’s murder from related cases where we have found harmless trial courts’ failure to provide a non-unanimity instruction. According to the dissent, repeated bludgeoning to the head by a hammer-like instrument, such as the one used by defendant, “is not like a gun fired at close range into a person; the victim’s death is not so assured.” Post at 302, 699 A.2d at 687 (citing Hightower I, supra, 120 N.J. at 412-14, 577 A.2d 99 (finding that defendant shot victim with a .32-caliber handgun from close range in the chest, neck, and head)). Incomprehensibly, the dissent also concludes that, unlike other cases, “there is no evidence that defendant took further steps to assure Ms. Schnaps’s death.” Post at 302, 699 A.2d at 687 (citing Hightower I, supra, 120 N.J. at 413, 577 A.2d 99 (finding that defendant dragged victim into freezer); Pitts, supra, 116 N.J. at 618 , 562 A.2d 1320 (noting that defendant took victim’s pulse)). We disagree. The inescapable inference created by the objective facts, especially the severity and number of Schnaps’s wounds, is that defendant intended to kill her.
- E -
Nor is defendant’s argument strengthened by the trial court’s delivery of a Gerald charge. Given this Court’s reversal of the conviction in the first trial, the inclusion of a Gerald charge in the second trial is understandable, if unnecessary. In reversing the conviction in the first trial, which included defendant’s confession, we did not predetermine the need for such a charge in a retrial in *152 which the confession was excluded. Likewise, the inclusion of charges on the lesser-included offenses of aggravated and reckless manslaughter do not compel the need for a Gerald/Mejia charge. Those charges reflect the trial court’s caution when instructing the jury.
- F -
We are unpersuaded also by defendant’s contention that he was entitled to a Mejia charge. Defendant bases that contention on the State’s acknowledgment that when defendant entered the victim’s apartment, he intended to commit only burglary, not murder. Similarly unpersuasive is defendant’s attempt to derive support from the State’s argument, made pursuant to N.J.S.A. 2C:11-3c(4)(c), that defendant, when committing aggravated assault on the victim, inflicted some blows not to kill, but to cause pain. Even if defendant did not intend to kill Schnaps when he first entered her apartment, the evidence reveals that he changed his mind once he began to assault her. Whether this occurred in a “brief moment,” as the dissent argues, or not is irrelevant. Post at 301, 699 A.2d at 686.
Furthermore, a Gerald/Mejia charge is not required simply because the prosecution relies on N.J.S.A. 2C:11-3c(4)(c). Overwhelming evidence establishes that even if defendant struck the first few blows merely to cause pain, he struck the others to kill. The trial court did not err in failing to tell the jury that it could return a non-unanimous verdict on whether defendant intended to kill. Defendant’s attack was “so wantonly brutal that the jury could have concluded only that the defendant intended to cause death.” Mejia, supra, 141 N.J. at 488, 662 A.2d 308 .
- III -
Defendant contends that the trial court’s instruction on murder improperly precluded the jury from considering the non-capital offense of felony murder. Specifically, defendant alleges that the instruction and the verdict sheet prevented the jury from *153 considering felony murder until after it first had found him guilty of purposeful-or-knowing murder. Defense counsel did not object to the charge or the verdict sheet. Hence, the issue arises as a matter of plain error under Rule 2:10-2. The issue is whether the error “is clearly capable of producing an unjust result.” We recognize that the charge was flawed, but conclude that the error was not capable of producing such a result.
- A-
Defendant was indicted “for purposely or knowingly causing Schnappes [sic] death or serious bodily injury resulting in death.” The indictment also included counts for second-degree robbery and second-degree burglary. In addition, the State relied on aggravating factor N.J.S.A. 2C:11-3c(4)(g) (the murder was committed during the course of a robbery and a burglary). Although defendant was neither indicted for, nor charged with felony murder, N.J.S.A. 2C:11-3a(3), the court, in accordance with Purnell, supra, 126 N.J. at 530-34, 601 A.2d 175 , instructed the jury on felony murder. A conviction for felony murder, however, does not render a defendant eligible for the death penalty. N.J.S.A. 2C:11-3c; Dixon, supra, 125 N.J. at 255 , 593 A.2d 266 . In Purnell , this Court held that the death penalty could not be imposed for a murder that was committed in the course of a felony if the jury was not permitted to consider the non-capital verdict of felony murder. Although the trial court here gave a felony-murder charge, the verdict sheet makes clear that the jury could not have considered a verdict on felony murder without first finding defendant guilty of purposeful-or-knowing murder.
- B -
The court instructed the jurors that page one of the verdict sheet provided them with four choices when considering the murder charge. They could find defendant not guilty, guilty of murder, guilty of aggravated manslaughter, or guilty of reckless *154 manslaughter. Page one did not present felony murder as an option.
The court instructed the jurors that if they found defendant not guilty of murder, they were to ignore pages two and three of the verdict sheet, and proceed directly to page four, where they were to consider the robbery count. Only if the jury found defendant guilty of murder were they to proceed to pages two and three. Page two directed the jury to determine whether defendant had committed the Wiling by his own conduct and purposely or knowingly. If the jury answered affirmatively, the verdict sheet directed them to page three. That page directed the jury to the Gerald issue, whether defendant had acted with the intent to Wll or to inflict serious bodily injury. It also directed the jury to consider whether defendant was guilty of felony murder. Thus, unless the jurors first found defendant guilty of purposeful-or-knowing murder, they would not have reached the felony-murder alternative. In effect, the verdict sheet distracted the jury from convicting the defendant of felony murder, but not purposeful-or-knowing murder.
In a capital case, “the jury must be given every opportunity to convict of the charge not carrying the death penalty.” Mejia, supra, 141 N.J. at 484, 662 A.2d 308 (quoting John M. Cannel, New Jersey Criminal Code, Annotated, Comment 13 to N.J.S.A. 2C:1-8(e)). Here, the combination of the jury charge and the verdict sheet led the jury away from rendering a non-capital verdict of felony murder. That was error.
On the facts of this case, however, the flaws in the charge and verdict sheet do not constitute plain error. Defendant has not advanced any plausible version in which the jury could have convicted him of felony murder without also convicting him of purposeful-or-knowing murder. Nor can we ascertain any such version from the record. In sum, the error was not clearly capable of producing an unjust result.
*155 - IV-
Following a Rule 104 hearing, the trial court permitted the prosecution to admit into evidence the results of a DNA test kit known as the “PM” or “polymarker” test. The kit, which is manufactured by Roche Laboratories and marketed by the Per-kin-Elmer Corporation, is sold under the trade name “AmpliType PM.” This polymarker evidence was an important link in tying defendant to the crime. We accept the admission into evidence of results of polymarker testing, which is used primarily on small samples of genetic material, such as blood stains.
On this record, we conclude that the scientific community generally accepts polymarker testing, including dot-intensity analysis. Generally speaking, dot-intensity analysis is a means of identifying a single sample from two sources, such as a blood stain that contains the blood of two people. Such samples may be present at the scene of a violent crime.
The State’s experts identified the genetic markers for the victim and the perpetrator. Through polymarker testing they determined that the box-spring sample, which contained the victim’s blood, also contained blood with the same genetic markers as defendant’s blood. The experts concluded that defendant’s genotype for the genetic markers was shared by only one-in-1,400 African Americans. We hold that the trial court did not err in admitting the testimony of the State’s experts about the results of the DNA tests. The weight of that evidence was for the jury.
DNA testing is an evolving science. The general acceptance or rejection of a test may change over time. Even a test that is accepted generally, moreover, may attract critics. One generally accepted DNA test involves restriction fragment length polymorphism (RFLP) analysis. Because the blood sample in this case was so small, the State’s experts could not use RFLP analysis. Instead, they used tests based on a Polymerase Chain Reaction (PCR): the HLA DQ ALPHA (DQ Alpha) and polymarker (PM) tests.
*156 We begin with a basic explanation of DNA. The explanation necessarily uses technical terms and describes scientific methods. Our purpose is to discuss the basic concepts to the extent necessary for comprehension of the trial court’s decision to admit the DNA evidence.
In the course of our discussion, we shall review objections raised by defendant and the dissent to the admission of the DNA evidence. Generally, the defense repeats arguments rejected by the trial court. The dissent, however, raises several objections not raised by the defense either at trial or on this appeal. Both the defense and the dissent share the objective of precluding the admission of DNA evidence proving that defendant murdered Irene Schnaps. Our scrutiny of the record leads to the conclusion that the trial court did not err in admitting the DNA evidence. The weight of the evidence was a matter for the jury.
- A-
1. Deoxyribonucleic Acid (DNA)
Deoxyribonucleic acid (DNA) is a molecule of genetic materials shaped like a double-helix or spiral ladder. In every person, each cell with a nucleus contains a copy of that person’s DNA. Thus, DNA serves as a blueprint for the human body.
The sides of the DNA helix or ladder are composed of two chains comprised of sugars and phosphates. Rungs or steps connect the two sides of the ladder. The rungs consist of pairs of molecules called “bases” or “nucleotides,” which consist of four types: adenine (A), cytosine (C), guanine (G), and thymine (T). Nucleotides from separate DNA strands bond in a specific order to form the rungs that connect the sides of the DNA ladder. C bonds only with G, and A bonds only with T. Thus, for example, if the nucleotides on one strand are CGAT, the corresponding nucleotides on the attached strand will be GCTA.
The order of the base pairs along the DNA molecule comprises an individual’s genetic code. Human DNA contains approximately *157 three to four billion base pairs, known as the “genome.” These base pairs govern the production of bodily proteins.
A gene is a sequence of nucleotides on a DNA strand responsible for producing a particular protein. The sequence of the nucleotides can vary. The possible sequences or variations are called “alleles.” Thus, an allele is simply a version of a gene.
A gene’s position on a chromosome is its locus. In different individuals, genes may be “polymorphic,” meaning that they may take different forms or contain different sequences of base pairs. The polymorphic genes, which vary from one person to another, provide the basis for DNA identification. Most DNA has no known function, but even non-functional DNA remains important in forensic analysis.
During mitosis, or cell division, each chromosome is copied. The paired nucleotides separate, dividing the chromosome’s DNA molecule into two separate strands. Free-floating nucleotides attach to the exposed nucleotides of the separated strands in accordance with the G-C, A-T rule. Thus, each strand reconstitutes identical DNA molecules. When the cell divides, these two identical chromosomes enter newly-created “daughter” cells. Each new cell has the identical genetic composition as the original cell.
All cells contain the same chromosomal composition. No two individuals, except identical twins, have the same nucleotide sequences throughout their DNA. DNA testing conducted on cells from various parts of the same body, whether blood, skin, semen, saliva, or hair will yield the same results. As in this case, DNA analysis can help identify donors of genetic material, such as blood.
2. Restriction Fragment Length Polymorphism, (RFLP)
At present, the most widely accepted DNA test is the RFLP analysis. See, e.g., Fishback v. People, 851 P.2d 884, 892 (Colo.1993) (holding that “no serious dispute exists as to whether the *158 techniques involved in RFLP analysis are generally accepted”); State v. Moore, 268 Mont. 20 , 885 P.2d 457, 468 (1994) (concluding that “the theory underlying DNA and RFLP technology is generally not open to serious attack and [] such evidence is widely admitted in various state and federal courts and jurisdictions”); State v. Streich, 163 Vt. 331 , 658 A.2d 38, 48 (1995) (noting that “we cannot find any recent decision under any standard of admissibility which refuses to admit the DNA match result based on” the RFLP technology). Recently, in State v. Marcus, the Appellate Division recognized that the scientific community generally accepts RFLP analysis. 294 N.J.Super. 267 , 683 A.2d 221 (1996). As Judge Skillman stated, “DNA testing by the RFLP method is generally accepted and is sufficiently reliable to warrant its admission in criminal cases.” Id. at 285 , 683 A.2d 221 . RFLP was not the DNA analysis employed in this ease. A brief description of RFLP, however, may be useful as background information.
RFLP focuses on non-functional regions of DNA known as variable-number tandem repeats (VNTRs). In these regions, which typically range from 500 to 10,000 pairs of nucleotides, a core sequence of approximately fifteen to thirty-five base pairs is repeated many times consecutively along the chromosome. The number of repeats varies among individuals. At a given locus or site on a chromosome, sequences with different numbers of repeated units are known as VNTR alleles. Because different VNTR alleles contain different numbers of repeats, these alleles can be identified by their lengths. National Research Council, The Evaluation of Forensic DNA Evidence 14-15 (1996) (NRG Report).
In RFLP analysis, the recovered DNA sample and the sample from the suspect are treated with a restriction enzyme, which seeks out a specific nucleotide pattern on the DNA helixes. It then fragments the molecules at those sites. Because of VNTRs, the locations of these sites, and the lengths of the resulting fragments, differ among individuals. Through a process called “gel electrophoresis” the DNA fragments are sorted by size and *159 split into single strands. These strands bond to a nylon membrane, where a specially treated and radioactively-tagged single strand of DNA, called a “genetic probe,” is applied. The genetic probe bonds with a targeted VNTR sequence.
The nylon membrane is then placed in contact with a, piece of X-ray film. The radioactivity of the probes exposes the film, producing a pattern of bands, like the bar-code on a box in a supermarket, where the probes have attached to VNTRs. This bar-code image is called an “autoradiograph” or “autorad.”
Fragments from different donors contain different numbers of repeat units, with a corresponding variation in the lengths of the fragments. Typically, radioactive probes need days or even weeks to expose the film. Id. at 18. Generally speaking, RFLP testing is time-consuming and may require months for a complete analysis. Ibid.
Comparison of the location of the bands reveals whether the targeted VNTR in the subject’s DNA matches the DNA from the recovered genetic material. That analysis can lead with a high degree of certainty to a correlation between the DNA samples.
The next step involves analysis of population statistics, which reveals the likelihood of a random match between the samples. Using single-locus probes, the probability of finding a random match between unrelated individuals on all bands of a DNA fingerprint is less than one in ten million. Using one multi-locus probe, the probability is about one in thirty-three billion. Thomas M. Fleming, Annotation, “Admissibility of DNA Identification Evidence,” 84 A.L.R.4th 313 , 324 (1991).
One problem with RFLP testing is that it requires a large quantity of high-quality genetic material. For example, it requires at least a quarter-sized blood stain or a dime-sized semen stain. Unless those samples are recovered when relatively fresh, they will degrade into fragments too small for RFLP analysis. Id. at 320 . Cellmark attempted RFLP testing in this case. The samples, however, were too degraded to permit RFLP analysis. *160 Thus, Cellmark turned to a newer technology, which involved Polymerase Chain Reaction (PCR).
3. PCR
When, as here, the quantity or quality of genetic material recovered from a crime scene is insufficient to allow RFLP analysis, forensic scientists have used the PCR process to amplify the DNA to produce an amount suitable for testing. The PCR process can copy a segment of DNA millions of times. NRC Report, supra, at 22-23. With the resulting genetic product, scientists can conduct “allele-specific probe” analysis. Fleming, supra, 84 A.L.R.4th at 322-23.
The PCR process copies DNA fragments similar to the way DNA replicates itself during mitosis. Through heating the DNA sample in a thermal cycler, the process separates the helix into separate strands. Primers composed of short DNA segments are added to define the target sequence of DNA. Then, a basic solution containing the enzyme DNA polymerase and the four basic nucleotides are added to the primed DNA sample. The added nucleotides pair with the exposed nucleotides on the separated target-strands in accordance with the G-C, A-T pairing rule. From the original DNA segment, two identical segments result. The thermal cycler runs through its cycle approximately thirty-two times, amplifying the original sample by a factor of two billion. Currently, PCR technology effectively amplifies only small regions of DNA. Accordingly, PCR cannot be used to amplify longer VNTRs for RFLP testing. NRC Report, supra, at 69-70.
PCR-based testing methods have several advantages over RFLP analysis. They are relatively simple processes and can yield results within a short period of time, often within twenty-four hours. Of particular importance to the present case, the PCR process also makes possible DNA tests on small amounts of genetic material.
A disadvantage of PCR-based tests, however, is that the identified genes have fewer alleles than VNTRs. Hence, scientists must *161 examine more loci to produce the same amount of information about the likelihood that two individuals share a profile. Id. at 71. Also, some of the loci examined by PCR-based tests are functional genes. Unlike non-functional VNTR markers, functional genes are more susceptible to natural selection, a susceptibility that might undermine their usefulness in matching DNA samples. Ibid. Contamination also is of concern in PCR testing. The technology is so efficient that even small contaminants can be replicated along with the targeted DNA. Ibid. Cellmark used two types of PCR-based tests in defendant’s case: the HLA DQ Alpha (DQ Alpha) and polymarker (PM) tests.
a. HLA DQ Alpha Test
The DQ Alpha test reveals an individual’s form of alleles for the human-leukocyte-antigen DQ Alpha gene. The purpose of the DQ Alpha test is to idéntify the genotype or the two alleles that comprise the DQ Alpha gene present in the DNA sample. That result is then compared with the DQ Alpha genotype of the suspect. If the genotypes match, then the suspect cannot be excluded as a possible donor. Genetics population databases then produce the frequency with which the suspect’s genotype appears in the population. Although eight alleles have been identified at the DQ Alpha locus, only six are commonly used in forensic work. Ibid. Each of those six alleles can be distinguished by specific enzyme probes. Ibid. The six alleles for DQ Alpha are denominated as 1.1, 1.2, 1.3, 2, 3, and 4. For the DQ Alpha gene, there are twenty-one possible pair combinations or genotypes.
To interpret the results, the test uses a test strip with six chemical dots. Each dot consists of a specific enzyme probe that selectively binds to one of the six DQ Alpha alleles. Because the probes, rather than the DNA, are fixed on the membrane, this is called a “reverse” blot. Ibid. This test strip is then immersed in a solution containing the PCR product. The alleles for DQ Alpha present in the PCR product then attach to their corresponding enzyme probe on the test strip. Where the alleles bond, the dots *162 turn blue. Two of the six dots will turn blue to indicate which two alleles constitute an individual’s genotype. If an individual is homozygous, meaning that the two DQ Alpha alleles are identical, only one dot will turn blue.
The DQ Alpha test performed on defendant’s blood revealed that his genotype for DQ Alpha is 4,4 or homozygous. Approximately 17% of the entire population (about one-in-six people) and 11.9% of the African American population (about one-in-eight) share that genotype.
DQ Alpha tests performed on a blood stain from the box-spring fabric indicated the presence of the DQ Alpha alleles 2 and 4. Schnaps’s genotype for DQ Alpha was 2,4.
If the blood stain on the box spring were from a single donor, defendant could have been excluded because he does not possess the 2 allele. Schnaps, whose genotype matched the alleles, however, could not be excluded. If, however, the blood on the box spring is from a mixed sample, i.e., from more than one donor, then defendant cannot be excluded. The reason is that the 4 allele, which defendant possessed, was present in the blood stain. Based on other evidence, the prosecution established that the box-spring stain was a mixed sample.
Courts in New Jersey and in other jurisdictions have admitted results of PCR technology and the DQ Alpha test as scientifically reliable. See State v. Dishon, 297 N.J.Super. 254, 277 , 687 A.2d 1074 (App.Div.), certif. denied, 149 N.J. 144 , 693 A.2d 112 (1997) (finding that testimonial hearing was unnecessary to establish the general acceptance of DQ Alpha DNA testing); State v. Williams, 252 N.J.Super. 369, 381 , 599 A.2d 960 (Law Div.1991) (holding that “overwhelming and persuasive evidence” pointed to general acceptance of PCR process and DQ Alpha test); State v. Haddock, 257 Kan. 964 , 897 P.2d 152 (1995) (admitting results of DQ Alpha test as scientifically reliable); People v. Palumbo, 162 Misc.2d 650 , 618 N.Y.S.2d 197 (Sup.Ct.1994) (same); State v. Gentry, 125 Wash.2d 570 , 888 P.2d 1105 , cert. denied, — U.S. -, 116 S.Ct. 131 , 133 L.Ed.2d 79 (1995) (same).
*163 Defendant does not contest the admissibility of the PCR/DQ Alpha test results. He objects, however, to the admissibility of the results of the polymarker test, the validity of which the dissent concedes. Post at 236, 699 A.2d at 654. Because of defendant’s objection, we briefly discuss the polymarker test.
b. The Polymarker (PM) Test
The PM test works like the DQ Alpha test, but instead of testing for the composition of one gene, it tests for six genes. The six genes tested in the PM test are: LDLR flow density lipoprotein receptor), GYPA (glycophorin A), HBGG (hemoglobin gamma-globulin), D7S8, and GC (Group Component). Each of those genes consists of combinations of either two or three different alleles. A blue-dot test, similar to that used in the DQ Alpha test, determines the genotype for each gene. As explained by Ms. Cooper, one of the State’s experts, the PCR test begins by amplifying the amount of DNA. Then, the DNA is passed over a polymere test strip. When the DNA finds its type on that locus, the dot changes color. Each combination of alleles is associated with a population frequency that is expressed as a percentage.
After ascertaining a sample’s genotypes and population frequencies for each of the five individual genes, a mathematical formula known as the “product rule” reveals the likelihood that another individual in the relevant population would share the test subject’s genotype for all five targeted genes. The product rule, which gives the profile frequency in a population as a product of coefficients and allele frequencies, rests on the assumption that a population can be treated as a single, randomly mating unit. NRC Report, supra, at 5. Under the product rule, the population frequencies for each of the six genotypes are multiplied by one another.
Defendant’s genotype for LDLR is present in 56% of the African-American population, his GYPA in 50%, his HBGG in 27%, his D7S8 in 45%, his GC in 17%, and his DQ Alpha in 11.9%. Applying the product rule, the prosecution’s expert testified that *164 one-in-170 Afincan Americans would share defendant’s genotype for the LDLR, GYPA, HBGG, D7S8, and GC loci. The product rule equation would be: .56 x .5 x .27 x .45 x .17 = .0058, or, expressed as a ratio, about one-in-170 African Americans. By including defendant’s DQ Alpha genotype frequency in the product rule equation along with the polymarker loci, only one-in-1400 African Americans would share defendant’s composite genotype for all six genes. The product rule equation would be: .56 x .5 x .27 x .45 x .17 x .119 = .00069. Expressed as a ratio, the result is about one-in-1400 African Americans.
4. The Dot-Intensity or Association-of-Alleles Technique
In addition to his general objection to the polymarker test, defendant contends that the polymarker test cannot accurately analyze a mixed-blood sample. At trial, the experts described this method of analysis of interpreting the polymarker test on a mixed-blood sample as involving “the association of alleles.” Scientific articles describe it as “dot-intensity” analysis, a description that we adopt generally in this opinion.
At the pretrial hearing, Dr. Word, one of the State’s experts, testified that the polymarker test is designed so that if a single blood source contributes a pair of heterozygous alleles (i.e., A, B or B, C but not A, A), the two alleles will turn blue in equal intensities. If, however, two or more blood donors contribute the same allele, that dot would be more intense or a darker blue than if an individual donor contributed only one such allele. The same result would follow if one blood donor contributed two of the same allele so as to result in a pair of homozygous alleles (i.e., A, A or B, B but not A, B). In sum, the determination whether a sample is from more than one source of blood depends on the intensity of the color of the dots.
Cellmark performed PM tests on three samples: (1) on a bloody towel, assumed to contain blood from the victim only; (2) on a sample of defendant’s blood; and (3) from a portion of the box-spring cover that contained a mixture of blood. The polymarker *165 test on the blood removed from the box spring revealed the presence of both possible alleles (A and B) for LDLR, GYPA, and D7S8, and all three possible alleles (A, B, and C) for HBGG and GC. An individual can possess, at most, two different alleles. Consequently, the presence of three different alleles at the HBGG and GC loci demonstrated that the DNA sample from the box spring was a mixture of blood from more than one individual.
Dr. Word testified that the PM test conducted on the mixed-blood sample from the box spring revealed two distinct sources. Two sets of alleles caused the color imbalances in the dots from the box-spring sample. On the test strip, some of the blue dots appeared darker, but others were lighter. None of the dots, however, was lighter than the control dot. Those dot-intensity imbalances resulted from the presence of some alleles in pairs and other singly.
Using dot-intensity analysis, Dr. Word explained that a theoretical subtraction of the victim’s blood from the PM results of the box-spring sample revealed the genotype of the second subject. She explained that if all three alleles for GC were present (A, B, and C) and the A allele-dot was darker on the test strip, the sample contained two A alleles, one B allele, and one C allele. The genotypes of the contributing donors, then, had to be either AB and AC, or AA and BC. No other combinations consisted of two A alleles, and only one each of B and C.
Based on dot-intensity analysis of the blood stain from the box spring, the State’s experts concluded that the blood could have been a mixture of defendant’s blood with that of Schnaps’s. Cellmark made only two assumptions in its analysis: (1) that Schnaps was a donor to the blood on the box-spring sample; and (2) that the blood was a mixture of two people.
The PM test for GC on the box spring revealed the presence of the A, B, and C alleles. The A dot was darker than the other two. That difference indicated that the composition of the GC in the sample consisted of two A alleles, plus the B and C alleles. If the sample had two donors, the possible combinations were AA and *166 BC, or AB and AC. Schnaps was AC type for GC. The remaining donor therefore had to be AB. Defendant’s genotype was AB.
The D7S8 test on the box-spring sample revealed the A and B alleles, with the A dot being darker. The only possible combination, then, was AA and AB. Schnaps was AA type for D7S8. The remaining donor had to be AB. Defendant’s genotype was AB.
The HBGG test revealed the A, B, and C alleles at equal intensities. Because no dot was darker, Dr. Word testified that the possible combinations could be only AA and BC, AB and CC, or AC and BB. Schnaps was BB type for HBGG. Cellmark concluded that the remaining donor, then, had to be AC. Defendant’s genotype was AC.
The GYPA test revealed A and B alleles with the A dot being darker. Schnaps was AA type for GYPA. The other donor had to be AB. Defendant was AB.
The LDLR test revealed A and B alleles with the B dot being darker. Schnaps was AB type for LDLR. The other donor had to be BB. Defendant’s genotype for LDLR was BB.
Based on those test results, the State’s experts concluded that neither Harvey nor Schnaps could be excluded as donors to the box-spring blood sample. As with the RFLP test, infra part rV.A.2., the second step involves analysis of population statistics. Our discussion of the statistics in the present ease is at infra part VI.
- B -
1. Standard of Review
The first question concerns the standard of appellate review of a trial court’s decision on the admissibility of DNA evidence. Generally, appellate courts review a trial court’s determination of the admissibility of evidence for an abuse of discretion. State v. Conklin, 54 N.J. 540, 545 , 258 A.2d 1 (1969). The question remains, however, whether the abuse-of-discretion stan *167 dard should apply to decisions concerning the admission of novel scientific evidence. We begin by recognizing that the best time to make the record on admission of such evidence is in a Rule 104 hearing.
The party offering the evidence bears the burden of proof. Windmere, Inc. v. International Ins. Co., 105 N.J. 373, 378 , 522 A.2d 405 (1987). Trial lawyers must make myriad choices in deciding how best to present or refute novel scientific evidence. Those choices construct the universe of discourse within which the trial court decides whether the scientific community considers the evidence acceptable generally. The choices also influence the presentation of the evidence to the jury and the record on appeal.
Unlike many other evidentiary issues, whether the scientific community generally accepts a methodology or test can transcend a particular dispute. People v. Miller, 173 Ill.2d 167 , 219 Ill.Dec. 43, 61 , 670 N.E.2d 721, 739 (1996) (McMorrow, J., concurring), cert. denied, — U.S. -, 117 S.Ct. 1338 , 137 L.Ed.2d 497 (1997). In determining the general acceptance of novel scientific evidence in one case, the court generally will establish the acceptance of that evidence in other cases. Jones v. United States, 548 A.2d 35, 40 (D.C.1988). Notwithstanding the trial court’s better position to shape the record and make factual determinations, appellate courts retain an important residual role for questions concerning the admission of scientific evidence. Like trial courts, appellate courts can digest expert testimony as well as review scientific literature, judicial decisions, and other authorities. To the extent that general acceptance focuses on issues other than a witness’s credibility or qualifications, deference to the trial court is less appropriate. Miller, supra, 219 Ill.Dec. at 60-62 , 670 N.E.2d at 738-40 (McMorrow, J., concurring).
When reviewing a decision on the admission of scientific evidence, an appellate court should scrutinize the record and independently review the relevant authorities, including judicial opinions and scientific literature. In the rapidly changing world of modem science, continuing research may affect the scientific *168 community’s acceptance of a novel technology. By reviewing post-trial publications, an appellate court can account for the rapid pace of new technology. The continuing review also recognizes that general acceptance may change between the time of trial and the time of appellate review. State v. Bible, 175 Ariz. 549 , 858 P.2d 1152 , 1189 n. 33 (1993), cert. denied, 511 U.S. 1046 , 114 S.Ct. 1578 , 128 L.Ed.2d 221 (1994); see also Hadden v. State, 690 So.2d 573, 579 (Fla.1997) (finding that an appellate court “should consider the issue of general acceptance at the time of appeal rather than at the time of trial”). But see Lindsey v. People, 892 P.2d 281 , 290-91 n. 25 (Colo.1995) (reasoning that Frye v. United States, 293 F. 1013 (D.C.Cir.1923), “requires nothing more than general acceptance at the time the evidence is admitted”). Moreover, by examining such additional information, an appellate court can prevent any injustice rendered by the admission or exclusion of the evidence at the trial level. Bible, supra, 858 P.2d at 1189 n. 33 (stating that if “the result obtained is the product of invalid scientific theory, there is no good reason to accept it simply because we were fooled at the inception of the inquiry”).
On this appeal, we do not decide whether a different standard of appellate review should apply to a trial court’s decision to admit or exclude expert testimony in civil cases, where the focus is not on whether the scientific evidence is generally accepted, but rather whether it derives from a reliable methodology supported by some expert consensus. Landrigan v. Celotex Corp., 127 N.J. 404, 417 , 605 A.2d 1079 (1992); Rubanick v. Witco Chem. Corp., 125 N.J. 421, 449 , 593 A.2d 733 (1991). In Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579 , 113 S.Ct. 2786 , 125 L.Ed.2d 469 (1993), the United States Supreme Court adopted essentially the same standard for federal courts in both civil and criminal cases. The question of the appropriate standard of appellate review for federal courts is currently before the United States Supreme Court. Joiner v. General Elec. Co., 78 F.3d 524 (11th Cir.1996), cert. granted, — U.S. -, 117 S.Ct. 1243 , 137 L.Ed.2d 325 (1997). We restrict our analysis to the standard of review of evidence that the trial court has found to be generally accepted.
*169 2. Standard for Admission of Expert Testimony
New Jersey Rule of Evidence 702, which is virtually identical to former Evid. R. 56(2), governs the admission of expert testimony. The rule provides:
If scientific, technical, or other specialized knowledge will assist the trier of fact to understand the evidence or to determine a fact in issue, a witness qualified as an expert by knowledge, skill, experience, training, or education may testify thereto in the form of an opinion or otherwise.
In effect, this rule imposes three basic requirements on the admission of expert testimony:
(1) the intended testimony must concern a subject matter that is beyond the ken of the average juror;
(2) the subject of the testimony must be at a state of the art such that an expert’s testimony could be sufficiently reliable; and
(3) the witness must have sufficient expertise to explain the intended testimony.
[State v. Kelly, 97 N.J. 178, 208 , 478 A.2d 364 (1984); N.J.R.E. 702, 1991 Supreme Court Committee Comment.]
Defendant does not contest that DNA testing is beyond the ken of the average juror. Likewise, the defense does not dispute the qualifications of Ms. Cooper or Dr. Word as experts in the field of DNA testing. The sole issue is whether the scientific community sufficiently accepted the DNA tests to justify admission of the testimony of the State’s experts.
In criminal cases we continue to apply the general acceptance or Frye test for determining the scientific reliability of expert testimony. In Frye, supra, the court wrote:
[W]hile courts will go a long way in admitting expert testimony deduced from a well-recognized scientific principle or discovery, the thing from which the deduction is made must be sufficiently established to have gained general acceptance in the particular field in which it belongs.
[ 293 F. at 1013-14 (emphasis added).]
In 1993, the United States Supreme Court abandoned Frye's general-acceptance standard as the exclusive test for admitting scientific testimony in favor of the more relaxed standards of Federal Rule of Evidence 702. Daubert, supra, 509 U.S. 579 , 113 S.Ct. 2786 , 125 L.Ed.2d 469 . Even before the United States Supreme Court decided Daubert , this Court had relaxed the test *170 for admissibility of scientific evidence in toxic-tort cases. Landrigan, supra, 127 N.J. at 404 , 605 A.2d 1079 ; Rubanick, supra, 125 N.J. at 421, 593 A.2d 733 . We have been cautious in expanding the more relaxed standard to other contexts. State v. Fertig, 143 N.J. 115, 126 , 668 A.2d 1076 (1996); State v. Spann, 130 N.J. 484, 509-10 , 617 A.2d 247 (1993); State v. J.Q., 130 N.J. 554, 572-73 , 617 A.2d 1196 (1993). Thus, the test in criminal cases remains whether the scientific community generally accepts the evidence. Spann, supra, 130 N.J. at 509, 617 A.2d 247 ; Windmere, supra, 105 N.J. at 386 , 522 A.2d 405 .
A proponent of a newly-devised scientific technology can prove its general acceptance in three ways:
(1) by expert testimony as to the general acceptance, among those in the profession, of the premises on which the proffered expert witness based his or her analysis;
(2) by authoritative scientific and legal writings indicating that the scientific community accepts the premises underlying the proffered testimony; and
(3) by judicial opinions that indicate the expert’s premises have gained general acceptance.
[ Kelly, supra, 97 N.J. at 210 , 478 A.2d 364 (citing State v. Cavallo, 88 N.J. 508, 521 , 443 A.2d 1020 (1982)).]
The burden to “clearly establish” each of these methods is on the proponent. Williams, supra, 252 N.J.Super. at 376 , 599 A.2d 960 .
Courts have applied this test in various contexts to evaluate the reliability of scientific evidence. See, e.g., Kelly, supra, 97 N.J. at 209 , 478 A.2d 364 (admitting expert testimony relating to battered woman’s syndrome); State v. Zola, 112 N.J. 384, 412-13 , 548 A.2d 1022 (1988) (admitting expert testimony that modified-chemical test detected presence of saliva on victim), cert. denied, 489 U.S. 1022 , 109 S.Ct. 1146 , 103 L.Ed.2d 205 (1989); Windmere, supra, 105 N.J. at 373 , 522 A.2d 405 (concluding that voice-print evidence does not derive from reasonably reliable scientific method); Romano v. Kimmelman, 96 N.J. 66, 82 , 474 A.2d 1 (1984) (holding breathalyzer scientifically reliable); State v. Hurd, 86 N.J. 525 , 432 A.2d 86 (1981) (admitting hypnotically refreshed testimony when subjected to strict safeguards ensuring reliability of hypnotic *171 procedure); State v. King, 215 N.J.Super. 504, 518-20 , 522 A.2d 455 (App.Div.1987) (finding isoenzyme test, which detects presence in blood of six distinct enzyme systems, held scientifically reliable); Williams, supra, 252 N.J.Super. at 378-83 , 599 A.2d 960 (holding PCR/DQ Alpha test and Gm/Km blood tests sufficiently reliable to be admitted at trial).
3. General Acceptance
Proof of general acceptance within a scientific community can be elusive. Windmere, supra, 105 N.J. at 379 , 522 A.2d 405 . Satisfying the test involves more than simply counting how many scientists accept the reliability of the proffered technology. Williams, supra, 252 N.J.Super. at 375 , 599 A.2d 960 . Proving general acceptance “entails the strict application of the scientific method, which requires an extraordinarily high level of proof based on prolonged, controlled, consistent, and validated experience.” Rubanick, supra, 125 N.J. at 436, 593 A.2d 733 . Essentially, a novel scientific technique achieves general acceptance only when it passes from the experimental to the demonstrable stage. Windmere, supra, 105 N.J. at 378 n. 2, 522 A.2d 405 .
General acceptance, however, does not require complete agreement over the accuracy of the test or the exclusion of the possibility of error. See Richard J. Biunno, Current N.J. Rules of Evidence, Comment 4 to N.J.R.E. 702; State v. Johnson, 42 N.J. 146, 171 , 199 A.2d 809 (1964). Neither is it necessary to demonstrate that the techniques, methodology, and procedures are infallible. Nor is it necessary that acceptance within the scientific community be unanimous. State v. Tate, 102 N.J. 64, 83 , 505 A.2d 941 (1986). Every scientific theory has its detractors. Windmere, supra, 105 N.J. at 379 , 522 A.2d 405 . Here, the State’s burden is to prove that the polymarker test and the interpretation of its results are non-experimental, demonstrable techniques that the relevant scientific community widely, but perhaps not unanimously, accepts as reliable.
*172 4. Polymarker Test
A proponent of scientific evidence can prove general acceptance through expert testimony, publications, or judicial opinions.
a. Expert Testimony
At the pretrial hearing, Dr. Word testified that the scientific community generally accepts the polymarker test as scientifically reliable. The dissent agrees. Post at 236, 699 A.2d at 654. Dr. Word explained that the polymarker test is technologically and procedurally similar to the well-established PCR/DQ Alpha test. Cellmark, moreover, conducted validation studies on the PM test. The studies, which were conducted in accordance with protocols established by the Technical Working Group on DNA Analysis Methods (TWGDAM), revealed that the PM test reliably produced accurate results. Approximately thirty to forty laboratories in the United States use the PM test either for casework or validation studies. Six of the better-known laboratories independently had tested the polymarker and likewise concluded that it was reliable. Those laboratories included: the Federal Bureau of Investigations (FBI), the Department of Justice, the Georgia Bureau of Investigations, the California Laboratory in Berkeley, the Center for Blood Research in Boston, the Regional Crime Laboratory at Indian River Community College, and Roche Biomedical Laboratories. Of all the laboratories using the PM kit, none had ever reported receiving an incorrect result from a properly performed test.
Defendant challenged the general acceptance of the polymarker test, asserting that some laboratories still subject it to validation studies. Defendant’s expert at the Rule 104 hearing, Dr. Robert Shaler, testified that polymarker testing was not yet appropriate for use in casework and that Cellmark’s validation procedures were flawed.
The trial court concluded:
Based upon the expert testimony of Dr. Charlotte Word, and the scientific literature admitted into evidence, PCR/PM has been sufficiently validated to be *173 used in casework; has been accepted by the relevant scientific community; and produces uniform and reasonably reliable results.
Our review of the record leads us to conclude that the scientific community has generally accepted the polymarker test. Dr. Word established that independent tests have validated the polymarker’s reliability and that highly-regarded laboratories have employed the test in casework. Only defendant doubts the reliability of the PM test.
b. Publications
Scholarly and scientific publications, moreover, approve the polymarker test. In support of the polymarker test, the State submitted one published article, George Herrin, Nicola Fildes & Rebecea Reynolds, “Evaluation of the AmpliType PM DNA Test System on Forensic Case Samples,” 39 J. Forensic Sci. 1247 (1994) (Herrin article), and two articles that since have been published: Nicola Fildes & Rebecca Reynolds, “Consistency and Reproducibility of AmpliType PM Results Between Seven Laboratories: Field Trial Results,” 40 J. Forensic Sci. 279 (1995) (Roche field study); Bruce Budowle, et al., “Validation and Population Studies of the Loci LDLR, GYPA, HBGG, and D7S8, and Gc (PM Loci), and HLA-DQx Using A Multiplex Amplification And Typing Procedure,” 40 J. Forensic Sci. 45 (1995) (FBI Report). All three of those documents concluded that the PM test was reliable for casework. Further, the State submitted a list of forty-four presentations, posters, lectures, seminars, and workshops in which forensic scientists discussed issues regarding polymarker-related research, testing, and results. Dr. Word had attended fifteen to twenty such lectures and had lectured on the reliability of the polymarker test at many of the meetings.
Defendant argues that the scholarly works were too few to support a conclusion of general acceptance. Further, defendant maintains that lectures do not provide effective forums for peer review. In addition, defendant alleges that Cellmark violated the national standards for DNA testing by failing to publish both the *174 results of its validation studies and the types of primers and probes that it uses.
The articles and lectures, however, support general acceptance of the polymarker test. Admittedly, prior cases have involved greater bodies of accumulated scholarship. See, e.g., Kelly, supra, 97 N.J. at 211 , 478 A.2d 364 (noting that there were “at least five books and almost seventy scientific articles and papers about the battered-woman’s syndrome”); Williams, supra, 252 N.J.Super. at 382 , 599 A.2d 960 (noting that six testifying experts had authored, cumulatively, close to 600 articles, many on PCR technology). We recognize, additionally, the correlation between the number of published articles and the general acceptance of a subject. Yet, we never have required a specific number of articles to satisfy the test of general acceptance. Rather, our focus always has been whether existing literature reveals a consensus of acceptance regarding a technology. In Windmere, supra, 105 N.J. at 383-84 , 522 A.2d 405 , for example, although ample literature existed on the subject of voiceprint analysis, the existing “journals [were] in disarray.” By contrast, all of the written works on the polymarker test agree that the test is reliable. Defendant produced no documents, published or pre-publication, suggesting anything to the contrary.
Further, “[u]nder appropriate circumstances, speeches, addresses, and other similar sources may be used to demonstrate the acceptance of a premise by the scientific community.” Kelly, supra, 97 N.J. at 211 n. 17, 478 A.2d 364 ; see also State v. Anderson, 118 N.M. 284 , 881 P.2d 29, 42-43 (1994) (rejecting claim that presentations, as opposed to formal publications, were inadequate as peer review). From the forty-four lectures and presentations, it appears clear that the forensic-science community has kept abreast of developments and has had adequate opportunity for peer review of PM testing.
Since the conclusion of defendant’s trial, moreover, the National Research Council, the members of which are drawn from the councils of the National Academy of Sciences, the National Acade *175 my of Engineering, and the Institute of Medicine, published The Evaluation of Forensic DNA Evidence (referred to supra as NBC Report), an update to their 1992 report, DNA Technology in Forensic Science. The report concludes that PCR-systems, including the polymarker, are “ready to be used.” NRC Report, supra, at 119. The report further confirms that the polymarker has been “validated with tests for robustness with respect to environmental insults,” and that “substantial information on population frequencies” exists for the polymarker loci. Id. at 72. We conclude that existing literature, combined with research shared at lectures and symposia, supports a finding that the polymarker test is generally accepted as reliable by the forensic science community.
c. Judicial Opinions
At the time of the Rule 104 hearing, both the State and the defense were unaware of any judicial opinion discussing polymarker evidence. See Wilkerson v. Pearson, 210 N.J.Super. 333, 336 , 509 A.2d 818 (Ch.Div.1985) (holding that absence of judicial opinions demonstrating acceptance by other courts of particular type of scientific technique should not, by itself, foreclose finding of general scientific acceptance and reliability). Before the Rule 104 hearing, however, a New York court had admitted polymarker evidence. People v. Morales, N.Y.L.J., Oct. 26, 1994, at 34 (N.Y.Cty.Ct.1994), aff'd, 227 A.D.2d 648 , 643 N.Y.S.2d 217 , appeal denied, 677 N.E.2d 301 (1996). In Morales, experts from the Center for Blood Research Laboratories, Yale University School of Medicine’s Department of Genetics, and the Office of the Chief Medical Examiner for New York testified in support of admission of the evidence. Curiously, the witness from the New York Medical Examiner supporting the admission of the polymarker evidence was Dr. Shaler, the same expert who testified against admission of polymarker evidence in the present case. The New York court concluded that “the People have met their burden in establishing that the PCR tests at issue here are sufficiently established to gain general acceptance in the scientific community and satisfy the standard of reliability.” Ibid.
*176 Since defendant’s trial in the present case, at least six other courts have held that polymarker testing is scientifically reliable. United States v. Beasley, 102 F.3d 1440, 1448 (8th Cir.1996), cert. denied, — US. -, 117 S.Ct. 1856 , 137 L.Ed.2d 1058 (1997) (holding that DQ Alpha and polymarker testing are sufficiently reliable under Daubert and have achieved general acceptance within relevant scientific community); United States v. Shea, 957 F.Supp. 331, 338 (D.N.H.1997) (finding PCR testing, including polymarker testing, reliable under F.R.E. 702); United States v. Lowe, 954 F.Supp. 401, 418 (D.Mass.1996) (finding that polymarker and another PCR-based test, D1S80, are sufficiently reliable under Daubert); Brodine v. State, 936 P.2d 545, 550-51 (Alaska.Ct.App.1997) (finding polymarker testing generally accepted in scientific community); People v. Pope, 284 Ill.App.3d 695 , 220 Ill.Dec. 309, 314 , 672 N.E.2d 1321, 1326 (1996) (finding that DQ Alpha and polymarker typing are generally accepted in scientific community under Frye); Keen v. Commonwealth, 24 Va.Ct.App. 795, 485 S.E.2d 659, 664 (1997) (rejecting defendant’s challenges to the polymarker test). In Pope, supra, the Illinois Court of Appeals found polymarker testing generally accepted in the scientific community even when the Frye hearing in that ease involved the testimony of only one witness, the State’s expert. Pope, supra, 220 Ill.Dec. at 314 , 672 N.E.2d at 1326 . Admission of the polymarker test in other jurisdictions supports our conclusion that the trial court correctly admitted the evidence in the present case.
We thus conclude that the trial court did not err in admitting expert testimony on the results of the polymarker test. We are satisfied that the polymarker technology is scientifically reliable and that Cellmark conducted the tests in accordance with established procedures.
5. Dotr-Intensity Analysis
Defendant asserts that even if the results of the polymarker test are admissible, dot-intensity analysis, the State’s method of interpreting the mixed-blood sample, is scientifically unreliable. The *177 dissent likewise rejects dot-intensity analysis. Indeed, the dissent goes so far as to assert that if dot-intensity analysis is rehable, “the results obtained would be inconsistent with defendant being the murderer.” Post at 261, 699 A.2d at 667.
At the Rule 104 hearing, dot-intensity analysis was presented as an integral part of polymarker testing. The Rule 104 hearing involved consideration of oral testimony and written evidence on the polymarker test and dot-intensity analysis. Both the defense and the State considered dot-intensity analysis as an application of the polymarker test, not as an issue apart from polymarker testing. In holding that the results of polymarker testing were admissible, the trial court implicitly approved dot-intensity analysis, which was the only use of the polymarker test on which the State relied.
Based on the record, as well as on posttrial publications and judicial opinions, we conclude that the trial court correctly allowed the State’s experts to testify about dot-intensity analysis. In so concluding, we recognize that a court must examine each step of a scientific process or technique. Kelly, supra, 97 N.J. at 210 , 478 A.2d 364 . Thus, we independently examine dot-intensity analysis to determine whether it has obtained sufficient acceptance to justify admission of its results into evidence.
a. Expert Testimony
At the pretrial hearing, the defense offered the testimony of Dr. Shaler and a written report by Dr. Blake, of Forensic Science Associates, both of whom disagreed with Dr. Word on the propriety of dot-intensity analysis. Dr. Shaler disputed Cellmark’s theory that the dot-intensity imbalances on the polymarker test strip represented the presence of allele pairs. He testified that such color imbalances occurred even on the DNA test strips of the single-donor control samples of defendant’s and Schnaps’s blood. For example, Dr. Shaler claimed to have detected intensity imbalances on defendant’s GYPA and HBGG loci and on the victim’s GC locus. According to the defense, those variances in the dot *178 intensities in Harvey’s and Schnaps’s control strips destroyed the integrity of the dot-intensity analysis of the mixed-blood sample taken from the box spring. The dissent agrees, asserting that “[t]o the degree that there are naturally occurring variances in dot intensities that cannot be predicted prior to the analysis, dot-intensity analysis disintegrates as a reliable and useful test.” Post at 169, 699 A.2d at 620-21. According to Dr. Shaler, the PM test of the box spring supported a calculation only of “all the second donor types which would be possible” to fill out the necessary alleles.
Defendant also asserts that color imbalances in the polymarker test strips may have been caused not by allele pairs, but by human errors such as contamination or manufacturing defects. Dr. Shaler, at the pretrial hearing and at trial, faulted Cellmark for not repeating the polymarker test procedure despite the possibility of error or contamination. He further stated that contamination, a manufacturing defect, or improper laboratory procedures caused the dot imbalances.
Our previous holding that the polymarker test is scientifically reliable, supra part IV.B.4.d., leads us to the conclusion that the foregoing challenges to dot-intensity analysis regarding Cellmark’s performance of the polymarker test, concern not the admissibility, but the weight of the evidence. See Marcus, supra, 294 N.J.Super. at 291 , 683 A.2d 221 (holding that interpretation of extra bands on autorads developed from bloodstains, “like an expert’s ability to perceive an abnormality on an x-ray, is a matter within the province of the jury”); Fishback, supra, 851 P.2d at 893 (reasoning that defendant’s challenge to techniques of RFLP analysis, including interpretation of autorads, concerns weight and not admissibility of DNA typing evidence under Frye); State v. Schweitzer, 533 N.W.2d 156, 160 (S.D.1995) (reasoning that DNA-expert’s conclusions regarding results of DNA test were issue of weight for jury to consider); State v. Kalakosky, 121 Wash.2d 525, 852 P.2d 1064, 1072 (1993) (holding that defendant’s assertions that specific laboratory procedures utilized to analyze DNA sam *179 pie were flawed, goes to weight of evidence, not admissibility). As such, the ultimate determination of these issues was properly left to the jury.
The State’s experts, Dr. Word and Ms. Cooper, differed from the defense expert, Dr. Shaler, in the interpretation of the dot intensities on the control strips. Defense counsel vigorously questioned the State’s experts whether the differences in the dots of the victim’s and defendant’s blood samples undermined the dot-intensity analysis of the sample from the box spring. On cross-examination, Ms. Cooper disputed Dr. Shaler’s claim that dot-intensity imbalances existed at the HBGG and GC loci on the defendant’s and Schnaps’s test strips. Ms. Cooper stated that “[t]he only place where I really see any type of a slight difference would be at the GYPA locus for Mr. Harvey.” Moreover, neither Ms. Cooper nor Dr. Word found any evidence that Cellmark had made a mistake in the conduct of the polymarker test. According to Ms. Cooper, the intensity imbalance on defendant’s GYPA locus was probably due to a variant allele present in some African Americans. Ms. Cooper explained that the difference in dot intensities at the GYPA locus was not due to errors in testing or to a manufacturing defect. Indeed, nothing in the record supports the defense’s conjecture that contamination or manufacturing defects caused any differences in dot intensities.
The dissent goes beyond the defendant’s arguments. For example, the dissent repeatedly concludes that the polymarker test kit used by the State was “designed solely to determine the presence or absence of certain alleles,” so that it at most can “potentially show that a mixture exists in certain circumstances.” Post at 244, 259, 699 A.2d at 658, 666.
The State, however, presented expert testimony at the Rule 104 hearing demonstrating that differences in intensities of the test-strip dots could reveal the blood donors to a mixed-blood sample. Dr. Word testified that the Perkins-Elmer Amplitype PM test strip was designed so that a sample from a single individual would produce similar dot intensities within each locus for which the *180 individual is heterozygous. If two or more blood donors contributed the same allele, or one blood donor contributed two of the same allele so as to result in a pair of homozygous alleles, that dot would be more intense than if one of that allele was contributed by an individual donor. Dr. Word further testified that Cellmark’s validation studies included a mixture-dilution study. That study provided Cellmark with information on the dilutions that were capable of detection and showed that the mixtures could be interpreted in many cases.
Contrary to the dissent’s characterization, see post at 255, 699 A.2d at 664, the testimony of the State’s expert supports the general acceptance of dot-intensity analysis. We conclude that the trial court reached the right decision in not preventing the jury from hearing the State’s DNA testimony.
The dissent nonetheless argues that certain omissions in the expert testimony of both parties reveal that dot-intensity analysis is unreliable. It maintains that the State’s inability to use dot-intensity analysis for the DQ Alpha test proves that the analysis does not work. It further states that the “DQ Alpha marker was retested using the PM testing strips.” Post at 265 n. 14, 699 A.2d at 668 n. 14. The record, however, contains no evidence of two sets of DQ Alpha test results. Likewise, the record contains no discussion of the application of dot-intensity analysis to the results of the DQ Alpha test. At trial, the defense did not challenge the absence of any such analysis. Hence, the record does not reveal whether dot-intensity analysis can be performed on a DQ Alpha test or whether the test for the DQ Alpha allele differs from the polymarker test. The Roche field study states that “[O]n DQA1 DNA probe strips, the probes are not as well balanced and the signal intensities cannot be used as easily to associate alleles from different sources” and that “it was easier to determine the major genotype on the PM DNA probe strips than the DQA1 DNA probe strips because the relative intensities of the dots could be compared.” Fields, supra, 40 J. Forensic Sci. at 284; see also Edward Blake, et al., “Polymerase Chain Reaction (PCR) Amplifi *181 cation and Human Leukocyte Antigen (HLA)-DQa Oligonucleotide Typing on Biological Evidence Samples: Casework Experience,” 37 J. Forensic Sci. 700, 706 (May 1992) (reasoning that for DQ Alpha test results, a “mixture cannot necessarily be detected, however, if two contributors to a mixture contribute no more than two alleles in total and contribute approximately equivalent amounts of DNA”); NRC Report, supra, at 130 (“Mixed samples can also lead to more complicated calculations with DQA, where some alleles are inferred by subtraction.”).
Finally, the dissent claims that the polymarker results from the HBGG marker of the box-spring sample prove that dot-intensity analysis does not work. Post at 263-265, 699 A.2d at 667-668. The HBGG marker results for the box spring were “A,B,C,” with all three alleles balanced in intensity. Schnaps’s type at the HBGG marker was “B,B.” According to dot-intensity analysis, the B allele should be more intense. Neither at trial nor on appeal, however, has defendant challenged the polymarker results or the dot-intensity analysis of the box-spring sample at the HBGG marker. Consequently, the State never has had an opportunity to meet the challenge. Perhaps defense counsel elected not to challenge the findings that the HBGG locus for strategic reasons. On the record before us, the unchallenged results of the dot-intensity analysis at the HBGG marker do not justify a reversal of defendant’s conviction. In an application for post-conviction relief, defense counsel may make such use of the polymarker results at the HBGG marker as is appropriate.
b. Publications
At the Rule 104 hearing, the State introduced three’ articles: the Roche field study, the FBI Report, and the Herrin article. See supra Part IV.B.4.b. All three articles discuss dot-intensity analysis. Not one states that dot-intensity analysis is unreliable. The articles go no further than to express caution when interpreting the results through dot-intensity analysis.
*182 The Roche field study was designed to determine the genotypes of either the major contributor or minor contributor, or both, to a mixed-blood sample. For example, in a mixed sample, where the intensity of the dots corresponding to the minor component was greater than or equal to the control dots, the study could not identify the major or minor component. Consequently, the study placed such a result in the uninterpretable category.
Apparently, the Roche field study was not a study of dot-intensity analysis for mixtures where the relative amounts of DNA for each donor were equal. The study, however, concluded that analyzing the balance of dots on a PM strip could be a “valuable asset of the system for the analysis of mixtures” and directed individual laboratories to develop policies for the interpretation of mixed-blood samples “based on experience and case history information.” Id. at 284-85. Here, Cellmark developed such interpretive methods.
The dissent contends that the FBI Report “flatly contradicts the assumptions of dot-intensity analysis.” Post at 280, 699 A.2d at 676. We read the FBI Report differently. The FBI Report stated that “[a]s a general rule, samples with two contributors of known PM types displayed PM types as predicted.” FBI Report, supra, at 49 (emphasis added). Each contributed to the profile and when the samples with two contributors of known PM types shared alleles in common the dot intensities were increased compared to alleles that were not shared. Ibid. Because the FBI, in its study, already knew the PM types of each donor, dot-intensity analysis was not necessary. Thus, contrary to the dissent’s assertion, the FBI Report did not refuse to draw any conclusions from dot-intensity imbalances. Post at 257, 699 A.2d at 665. Rather, the FBI Report acknowledged that mixtures of donors sharing the same alleles resulted in an increased dot intensity.
The dissent argues further that the Herrin article “did not conclude that dot-intensity analysis was sufficiently reliable to warrant its use in an actual criminal case.” Post at 258, 699 A.2d at 665. In fact, the Herrin article supports dot-intensity analysis, *183 especially where the victim’s known allele profile at the relevant locus is homozygous:
Comparison of the dot intensity within loci allowed deduction of types at some loci even when separation of DNA from sperm and non-sperm cells was not complete. This feature may prove to be very useful in routine casework____In this case the non-sperm fraction HBGG locus produced 3 dots with the A allele being approximately twice as intense as the B and C alleles (indicating that at least 2 A alleles were present). By comparison with the known sample from the victim in this case (HBGG AA), it is possible to assign the A alleles to the victim, and know that the B and C alleles originated with another individual(s).
[Herrin et al, supra, 39 J. Forensic Sci. at 1249-50 (emphasis added).]
Recent publications enhance the acceptance of dot-intensity analysis. The NRC Report states:
Mixed samples are sometimes found in crime situations — for instance, blood from two or more persons at the scene of a crime____ In many cases, one of the contributors — for example, the victim — is known, and the genetic profile of the unknown is readily inferred. In some cases, it might be possible to distinguish the genetic profiles of the contributors to a mixture from differences in intensities of bands in an BFLP pattern or dots in a dot-blot typing; in either case, the analysis is similar to the unmixed case.
[NRC Report, supra, at 129 (emphasis added).]
Moreover, Dr. Word recently has published an article validating the use of the PM kit for use on mixed-blood samples. Charlotte J. Word et al., “Summary of Validation Studies from Twenty-Six Forensic Laboratories in the United States and Canada on the Use of the AmpliType PM PCR Amplification and Typing Kit,” 42 J. Forensic Sci. 39 (1997).
Our review of the relevant literature leaves the impression that dot-intensity analysis is an esoteric topic of interest to a limited scientific community. Within that limited community, however, the analysis has been sufficiently accepted to permit the jury to hear about it. We recognize that, as occurred in the trial below, dot-intensity analysis provides an opening for cross-examination and contradictory expert testimony. That opening, however, should not deprive the jury from hearing testimony about the analysis. We also recognize that other eases considering the general acceptance of scientific innovations have involved a greater number of scientific articles. See supra Part IV.B.4.b. No *184 published article, however, rejects dot-intensity analysis. As previously discussed, the trend supports acceptance of the test.
c. Judicial Opinions
Although no court has discussed dot-intensity analysis at length, the United States District Court for the District of New Hampshire recently accepted as reliable under Daubert the premise underlying this interpretive method. In Shea, supra, the defendant argued that the polymarker test should be excluded because PCR cannot reliably detect mixtures of more than one person’s DNA. 957 F.Supp. at 339 . The district court rejected that argument, finding persuasive the government expert’s testimony that “an examiner -will be able to identify a mixture from observable differences in the relative strengths of the signals indicated on the PCR test strips, except in extremely unusual circumstances.” Id. at 340 .
d. New Jersey Rule of Evidence 403
Finally, the dissent argues that even if the DNA evidence derives from a generally accepted methodology, the evidence’s prejudicial effect outweighs its probative value. Post at 270, 699 A.2d at 671. In particular, the dissent challenges the assumption that only two people provided blood to the box-spring sample and that the victim’s and suspect’s blood were present in equal amounts. The argument is more theoretical than real. Nothing in the record suggests the presence of more than two persons at the crime scene.
In general, whether evidence should be excluded under New Jersey Rule of Evidence 403 because its prejudicial effect outweighs its probative value is an issue remitted to the discretion of the trial court. State v. Wilson, 135 N.J. 4, 20 , 637 A.2d 1237 (1994). Only when the trial court commits a clear error of judgment does an appellate court disturb the trial court’s decision. State v. DiFrisco, 137 N.J. 434, 496 , 645 A.2d 734 (1994) (DiFrisco II), cert. denied, — U.S. -, 116 S.Ct. 949 , 133 L.Ed.2d 873 *185 (1996); State v. Koedatich, 112 N.J. 225, 313 , 548 A.2d 939 (1988) (Koedatich I), cert. denied, 488 U.S. 1017 , 109 S.Ct. 813 , 102 L.Ed.2d 803 (1989).
We find no error in the admission of the DNA evidence. The probative effect of the evidence is that the DNA test results showed that defendant could not be excluded as a contributor to the box-spring blood sample. Without specifying how the prejudicial effect of the evidence outweighs its probative value, the dissent suggests possible avenues of inquiry that defense counsel might have pursued. Suffice it to say that defense counsel made a different choice, one that involved the cross-examination of the State’s experts concerning the dot-intensity analysis of the blood. We perceive no reason to disturb the trial court’s ruling admitting the DNA evidence.
- V-
We next evaluate defendant’s argument that the trial court violated his constitutional right to present a defense by restricting examination of expert witnesses to potential flaws in the administration of the polymarker test.
- A-
After holding that the polymarker kit was admissible, the trial court precluded further challenges to admissibility at trial. The court’s ruling, however, did not prevent defendant from introducing evidence relevant to the weight or credibility of the expert testimony.
In accordance with that ruling, the trial court prohibited defendant from attempting before the jury (1) to cross-examine the State’s experts on Cellmark’s validation studies and (2) to elicit testimony from Dr. Shaler that the FBI did not use the polymarker test on mixed-blood samples. Defendant claims that the trial court committed reversible error when it barred him from cross- *186 examining on these issues. To evaluate the defense’s argument, it is necessary to review the scope of the expert-witness testimony.
- B -
The State’s first DNA expert, Ms. Cooper, explained the results of the DQ Alpha and Polymarker tests conducted on crime scene samples and blood samples taken from defendant. Ms. Cooper also explained that before employing the PM test in its lab, Cellmark conducted a validation study.
The defense cross-examined Ms. Cooper on the dot-intensity imbalances in defendant’s PM test. Defense counsel sought to elicit that Cellmark had not conducted the PM test under the proper conditions and had failed to follow prescribed procedures. Ms. Cooper conceded that dot imbalances could result from improper hybridization or wash temperatures, improper salt-solution concentrations, or improperly-timed stringent washes. She disputed that discernible dot imbalances appeared on defendant’s HBGG and GC loci and explained that variations could occur at the GYPA locus. Because the positive control conducted with the test appeared normal, she did not investigate possible causes for the imbalances. Defense counsel also questioned Ms. Cooper on the possibility that by lifting the lid of the thermal cycler during the amplification process, she could have affected the accuracy of the tests.
Dr. Word testified that she reviewed all of Ms. Cooper’s work, and that she agreed with all of Ms. Cooper’s results. At one point during direct examination, the prosecutor inquired about a list of presentations on the PM test. Concerned that the prosecutor was trying to bolster the reliability of the PM test, the trial court precluded the inquiry.
On cross-examination, defendant pressed Dr. Word on the dot imbalances and on the possibility that Cellmark had not followed correct testing procedures. Dr. Word acknowledged that Cell-mark did not know how many people contributed to the mixed-blood sample recovered from the box spring.
*187 On redirect, Dr. Word testified that Cellmark had performed validation studies with the PM test. When the prosecutor tried to inquire into the nature and conclusions of Cellmark’s validation study, defense counsel objected successfully.
According to the defense expert, Dr. Shaler, Cellmark’s PM test results were flawed and Cellmark’s method of interpreting the test was “scientifically indefensible.” Dr. Shaler emphasized the presence of dot imbalances to the jury and faulted Cellmark’s technicians for not doing the tests twice. He also raised the possibility that Cellmark’s test strips were defective.
Dr. Shaler further testified that he did not believe in dot-intensity interpretation, stating that he had a “philosophical difference” with the State’s experts. Accordingly, he disputed Cell-mark’s thesis that the defendant could be linked to the box-spring stain. Defense counsel requested a side-bar conference because he wanted to ask Dr. Shaler about Cellmark’s validation work. The court responded that it deemed inappropriate the inquiry about validation because the inquiry was directed at the admissibility, not the weight, of the evidence.
Later, on redirect, Dr. Shaler restated his view that associating alleles was an unscientific method of analyzing a mixed-blood sample. Defense counsel then presented Dr. Shaler with an article asserting that the FBI did not use the dot-intensity analysis technique. The State objected. At side-bar, defense counsel explained that he did not believe that the article went to admissibility, but rather to the weight of Dr. Shaler’s testimony that associating alleles was not a valid interpretive technique. The prosecutor responded that the article went to admissibility and that Dr. Shaler already had testified to his belief that other scientists did not believe in dot-intensity analysis. The trial court sustained the State’s objection.
- C -
The Sixth Amendment to the United States Constitution and Article 1, paragraph 10 of the New Jersey Constitution *188 guarantee a criminal defendant’s right to confront witnesses. The right to cross-examine is an essential element of that right. State v. Budis, 125 N.J. 519, 530-31, 593 A.2d 784 (1991). A criminal defendant, therefore, may cross-examine an expert witness for the State on the facts, methodology, and rationale underlying the expert’s opinion. State v. Martini, 131 N.J. 176, 264 , 619 A.2d 1208 (1993) (Martini I), cert. denied, — U.S. -, 116 S.Ct. 203 , 133 L.Ed.2d 137 (1995); see also N.J.R.E. 705 (“The expert may ... be required to disclose the underlying facts or data on cross-examination.”). The scope of cross-examination, however, rests within the sound discretion of the trial court. Martini I, supra, 131 N.J. at 263 , 619 A.2d 1208 . Thus, a defendant’s constitutional right to confrontation does not guarantee unlimited cross-examination of a witness. Delaware v. Fensterer, 474 U.S. 15, 20 , 106 S.Ct. 292, 294 , 88 L.Ed.2d 15, 19 (1985).
Here, the trial court properly ruled that defendant could not relitigate admissibility issues that the court had determined. The court limited the parties to presenting evidence that went to the weight of the polymarker test results.
1. Validation Studies
Without merit is defendant’s argument that the trial court violated his confrontation rights by refusing to allow him to cross-examine Cellmark’s validation studies. Defense counsel never attempted to cross-examine the State’s experts on that matter. To the contrary, defense counsel objected when the prosecutor attempted to elicit testimony from Dr. Word on Cellmark’s validation trials. The dissent therefore misleads when it states that the trial court did not permit defendant to examine the scientific experts on Cellmark’s validation studies. Post at 276, 699 A.2d at 674.
The trial court properly precluded defendant from eliciting testimony through his own expert about Cellmark’s validation studies. The issue of Cellmark’s validation studies on the poly-marker more properly concerns the reliability of the polymarker. *189 As such, the issue goes to the admissibility of the test and not its weight.
We are convinced the trial court did not compromise the defendant’s confrontation rights. As the record reveals, defense counsel cross-examined the State’s experts on their methodologies and on the results from the PM tests.
2. FBI Report
The trial court should have allowed defendant to elicit testimony from Dr. Shaler about an article indicating that the FBI did not use the association-of-alleles or dot-intensity technique. The error, however, was harmless. R. 2:10-2.
As previously explained, supra part IV.B.5., some of defendant’s criticisms regarding the dot-intensity technique bore on the weight, not the admissibility of the DNA evidence. Thus, the court should have permitted defendant to elicit testimony about the article, which went only to the weight of the State’s evidence that it could determine defendant’s identity from the mixed-blood sample taken from Schnaps’s box spring.
The error, however, was not clearly capable of producing an unjust result. R. 2:10-2. Dr. Shaler tried to prove that dot-intensity analysis was unscientific. He also testified that other forensic scientists agreed. Through his testimony, the jury knew that some scientists questioned the validity of dot-intensity analysis.
Knowledge of the FBI’s position would have added only limited weight to defendant’s argument. As previously discussed, supra part IV.B.5., the FBI article did not, as the dissent states, contradict dot-intensity analysis. Post at 256-258, 280, 699 A.2d 664 -665, 676. Rather, the FBI Report urged caution when interpreting evidentiary samples that potentially may be from more than one donor. FBI Report, supra, at 52. The article also states, however, that mixtures of donors sharing the same alleles resulted in an increased dot intensity. Id. at 49.
*190 - VI -
Defendant next argues that Cellmark improperly computed the one-in-1,400 number associated with the prosecution’s DNA evidence. Specifically, defendant alleges that Cellmark improperly calculated its product-rule computation; failed to inform the jury of the margin of error associated with such statistical calculations; and improperly assumed that the contributor to the mixed-blood sample was an African American. In addition to echoing the defendant’s criticisms, the dissent urges the necessity of an independent hearing for the admission of the statistical evidence. We find, however, that the trial court did not err in admitting statistic evidence tending to show that defendant could not be excluded as a contributor to the blood found at the crime scene.
- A-
Cellmark concluded that Harvey’s genotype for all of the six genes studied in both the PM and the DQ Alpha tests was common to only one-in-1,400 African Americans. In reaching that conclusion, Cellmark consulted databases of genetic frequencies for each genotype and multiplied those figures together in accordance with the product rule.
Cellmark used two population-frequency databases. One derived from Cellmark’s own study of fifty African Americans, some of whom were Cellmark employees, and from “paternity work” blood samples done at the lab. Cellmark also referred to a database compiled by Roche derived from a sample of 100 African Americans. Defendant does not challenge the adequacy of Cell-mark’s databases. Indeed, Dr. Shaler used the same databases in his calculations.
As mentioned above, defendant’s DNA tests revealed the following results:
LDLR: Genotype BB = 56% of African Americans
GYPA: Genotype AB = 50% of African Americans
HBGG: Genotype AC = 27% of African Americans
D7S8: Genotype AB = 45% of African Americans
*191 GC: Genotype AB = 17% of African Americans
DQ Alpha: Genotype 4,4 = 11.9% of African Americans
According to the prosecution’s experts, someone with the foregoing genetic make-up could not be excluded as a donor to the mixed-blood sample recovered from the victim’s box spring.
To determine the percentage of African-American individuals who would share defendant’s genotype for all six genes, Cellmark multiplied genotype frequencies by one another in accordance with the product rule. See supra part IV.A.3.b. Application of the product rule indicated that defendant’s genotype for all six genes was common to approximately one-in-1,400 African Americans.
On appeal, defendant alleges that Cellmark’s one-in-1,400 figure was incorrect because it did not include the percentage of African Americans who could have matched the mixed-blood sample. Defendant argues that this alleged error arose because the DQ Alpha percentage used in Cellmark’s product-rule calculation was wrong. The dissent agrees. Post at 283-285, 699 A.2d at 678-679.
The DQ Alpha test conducted on the box-spring sample revealed the presence of the 2 and 4 alleles. It was not possible to associate alleles with the DQ Alpha test. The parties agree that the DQ Alpha test revealed all the possible genotypes that could have combined to reveal the presence of the 2 and 4 alleles: 2,2; 2,4; 4,4. Because defendant’s DQ Alpha genotype was 4,4, he could not be excluded as a potential donor if two people had contributed to the box-spring stain.
Defendant argues that the population frequencies for each of these three genotypes (2,2; 2,4; and 4,4) should have been added together before inserting a DQ Alpha statistic into the product-rule calculation. According to defendant, individuals who share defendant’s five polymarker genotypes and who have a DQ Alpha genotype of either 2,2; 2,4; or 4,4 — not just 4,4 — could not be excluded from the mixed-blood, box-spring sample.
*192 Evidence for the entire population revealed the population frequencies for only two of these three possible genotypes: 9% of the population had the 2 and 4 alleles, and 17% had the 4 and 4 alleles. On that basis, defendant argues that at least 26% of the population (17% + 9%) had a DQ Alpha genotype that would correspond to the box-spring sample. Therefore, defendant alleges that Cellmark should have used a DQ Alpha value of 26% rather than 17% (adjusted to 11.9%, taking race into account) when it conducted the product-rule calculation. Defendant contends that substituting the 26% DQ Alpha value yields a result of .0015 or one-in-666. Thus, defendant posits that one-in-666 individuals could have contributed genetic material consistent -with that detected in the box-spring sample. In sum, defendant concludes that the State unfairly prejudiced him by stating that one-in-1400, instead of one-in-666 African Americans, could have provided the sample.
The prosecution did not present the one-in-1400 figure to prove the percentage of African Americans whose genetic compositions could be comparable with the PM/DQ Alpha profile of the box-spring sample. Nor did the prosecution, as the dissent states, “assert[] that the blood recovered from the scene revealed the ‘4,4’ DQ-Alpha genotype.” Post at 283, 699 A.2d at 678. Rather, the prosecution used the DNA evidence to demonstrate that defendant could not be excluded as a donor to the mixed-blood sample and that one-in-1400 African Americans shared his composite genotype.
On the State’s case, Ms. Cooper testified:
Prosecutor: Now, using the product rule, if you use the four, four, based upon your calculation and did as you indicated with a polymarker, what percentage do you come up with?
Cooper: For African-Americans having the polymarker types we have indicated and an individual having a four, four DQ Alpha type, the number is approximately 1 in 1400 in African-Americans.
Prosecutor: Let’s mark this down the bottom. You can excuse one thousand three hundred and ninety-nine African-Americans from having these characteristics, is that correct?
*193 Cooper: Again, these numbers are just giving you an idea how rare or common, how these different types occur in a given population. And if you have a random population of approximately 1400 people, the chances are at least 1 of those people would have those particular polymarker and DQ Alpha type.
So described, the one-in-1400 evidence was relevant to show that defendant’s relatively rare composite genotype could not be excluded by the PM/DQ Alpha tests as a contributor to the box-spring sample. On cross-examination, moreover, Ms. Cooper testified that defendant’s specific DQ Alpha marker of 4,4, which occurred in seventeen percent of the population, constituted millions of people.
In addition, Ms. Cooper testified about statistics that did not include Harvey’s DQ Alpha results. She stated that multiplying the frequency calculations of each of Harvey’s PM loci showed that approximately one-in-170 African Americans shared Harvey’s genotype at the LDLR, GYPA, HBGG, D7S8, and GC loci.
Defendant now argues that the prosecution should have presented a ratio of the individuals whose polymarker genotypes would match defendant’s and whose DQ Alpha genotype was either 2,2; 2,4; or 4,4. That ratio, according to defendant, is approximately one-in-666. Defense counsel adduced no testimony in support of that ratio at trial. It is too late in the proceeding for defendant to insist that the State should have presented statistical evidence that defendant now believes would have been helpful at trial.
In addition, we note that the trial court, pursuant to defense counsel’s request, instructed the jury that statistical evidence does not relieve the jury of its obligation to determine the ultimate question of guilt. Specifically, the trial court stated:
Now, you heard testimony from DNA experts, from both the State and the Defense. Some of the testimony was expressed to you in terms of percentages. You must determine whether the State, again, has proven each and every element of the these [sic] charges beyond a reasonable doubt, and no testimony couched in terms of percentages or probabilities can relieve you of your obligation to make that determination.
At trial, the State derived its statistical evidence from genetics-population databases submitted to the trial court at the Rule 104 *194 hearing. Dr. Word testified that the databases were compiled from Cellmark’s own study of fifty African Americans and a' database created by Roche Molecular Systems, which was derived from a Roche study of 100 African Americans. She further explained that Cellmark’s polymarker databases were “essentially the same” as those used by other prominent forensic laboratories around the country. Dr. Word also testified to the use of the product rule to derive a composite frequency for defendant’s six-loci genotype.
At the Rule 104 hearing, the defense’s expert, Dr. Shaler, did not contest the accuracy of Cellmark’s databases. Instead, he relied on them in his own statistical calculations. Although the defense still does not criticize the databases, it contends that the State’s population databases were not large enough to be an accurate sampling of the population. Post at 291, 699 A.2d at 682.
In addition, the defense never sought to introduce evidence disputing the general acceptance or the mathematical soundness of the product rule. Even on this appeal, the defense does not challenge the use of the product rule. Indeed, the defense states that “everyone agrees that the product rule is absolutely valid.” The dissent, however, maintains that the trial court erred in failing to hold an admissibility hearing on the reliability of the product rule. Post at 293, 699 A.2d at 682. In particular, the dissent argues that the State never established the independence of the loci tested, post at 290, 699 A.2d at 681, and that the use of the “unmodified” product rule was erroneous, post at 286, 290, 699 A.2d at 679, 681.
On this record, the dissent’s arguments are particularly unpersuasive. First, publications reveal that statistical databases used by other laboratories for DQ Alpha and PM loci are often constructed with small groups of blood donors. See, e.g., Kwang Man Woo & Bruce Budowle, “Korean Population Data on the PCR-Based Loci LDLR, GYPA, HBGG, D758, Gc, HLA-DQA1 and D1S80,” 40 J. Forensic Sci. 645 (1995) (obtaining blood from 116 *195 unrelated Korean individuals); Jeanne M. Hayes et al. & Maya Freund, “Arab Population Data on the PCR-Based loci: HLADQA1, LDLR, GYPA, HBGG, D758, Gc and D1S80,” 40 J. Forensic Sci. 888 (1995) (collecting ninety-four blood samples from unrelated Arabs); see also Pope, supra, 220 Ill.Dec. at 312 , 672 N.E.2d at 1324 (finding that “[b]ecause the PCR polymarker systems are two allele or three allele, the FBI may rely on a smaller database. Thus, the PCR Caucasian database contains only 145 individuals”).
Second, the trial court found that the underlying databases were reliable. In light of that finding, questions regarding the size of a database go to the weight of the evidence, not its admissibility. See People v. Adams, 195 Mich.App. 267 , 489 N.W.2d 192, 198 (1992) (holding that, in face of expert testimony that database was valid, questions concerning size of database and statistical conclusions drawn from it went to weight, not admissibility, of evidence), modified in part on other grounds, 441 Mich. 916 , 497 N.W.2d 182 (1993); State v. Copeland, 130 Wash.2d 244 , 922 P.2d 1304, 1320-21 (1996) (holding that questions regarding size of FBI’s population databases was matter of weight once principle that frequency calculations could be made from an adequate database was determined to be generally accepted). Even on appeal, the defense does not challenge the size of Cellmark’s databases. See Fishback, supra, 851 P.2d at 893 (admissibility established because evidence uncontradieted).
The dissent’s contention that the trial court on its own motion should have conducted an independent Rule 104 hearing on the product rule also is without merit. The product rule assumes that each of the multiplied events (i.e., the matches at each allele) has occurred independently of one another. The State’s witnesses testified at the pretrial hearing and at trial that the population frequencies of the genes examined in the polymarker and DQ Alpha tests satisfied that requirement. Each derives from a gene located on a different part of the chromosome. Defendant never challenged the independence of the loci. At the pretrial hearing, *196 Dr. Shaler used the same version of the product rule as the State to compute his statistical figures. Furthermore, he testified that those loci were “independently inherited.” See also FBI Report, supra, at 53 (“The distribution of the genotype frequencies for the various PM loci (as well as HLA-DQa) meet HWE [Hardy-Weinberg expectations], and there is little evidence for association of alleles across loci (for the PM loci, HLA-DQa, and D1S80) for our African American, Caucasian, southeastern Hispanic, and southwestern Hispanic population databases. The data demonstrate that valid estimates of a multiple loc

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Source: Frix Law Library, https://www.frixlaw.com/law-library/cases/9643196. Public record. Not legal advice.