(This syllabus is not part of the opinion of the Court. It has been prepared by the Office of the Clerk for the convenience of the reader. It has been neither reviewed nor approved by the Supreme Court. Please note that, in the interests of brevity, portions of any opinion may not have been summarized).
Argued May 4, 1994 -- Reargued September 27, 1994 (A-15)
Argued September 27, 1994 (A-42-94)
Decided May 4, 1995
STEIN, J., writing for a unanimous Court.
The issue in these appeals is the admissibility of expert testimony by the State in drug-distribution cases
to explain techniques commonly used by drug dealers.
Charles Marshall Berry was stopped while driving on Interstate 80. Berry was unable to produce a valid
driver's license and appeared extremely nervous. The officer asked Berry and his two passengers to exit the
vehicle; he then conducted patdown searches. The officer noticed that one of the passengers had a plastic bag
in his mouth. The plastic bag contained a yellow chunky substance that the officer suspected was cocaine. Later
laboratory analysis revealed the substance to be 17.90 grams (.63 ounces) of cocaine. The officer arrested all
three occupants of the vehicle.
Berry and his two passengers were transported to the Totowa Barracks, where it was learned that the
passengers were juveniles. A search at the Barracks disclosed a plastic bag containing one-hundred smaller, clear
plastic bags in the sock of the same juvenile who had had the cocaine in his mouth.
Berry was charged with possession of cocaine and possession with intent to distribute. At trial, the trial
court qualified an officer of the Bergen County Prosecutor's Office as an expert in "narcotics and narcotics
distribution." This officer was presented with a hypothetical set of facts that mirrored the facts and circumstances
testified to by the arresting officer. The officer stated his conclusion that based on the value and high quality
of seized cocaine, there was no question that it was possessed for resale and distribution.
The officer was asked the significance of the presence of the two juveniles in a vehicle. He testified that
drug dealers traveling to New York City to purchase drugs often use juveniles as "mules" to carry the drugs in
the hope of avoiding serious criminal charges in the event of apprehension. On cross-examination, the officer
testified that all three occupants of the vehicle possessed the cocaine with intent to repackage and resell it.
The Appellate Division reversed Berry's convictions, concluding that the expert's opinion could not be
used to convert Berry's presence in the vehicle into active participation. One member dissented, and the State
filed an appeal as of right.
In the second appeal, Dwayne Cannon had been observed by members of the Jersey City Police
Department Narcotics Task Force receiving money for what appeared to be several vials of cocaine. The police
later stopped and searched the purchaser finding four vials of cocaine. Cannon was then observed handing the
money he had received to an unidentified male who immediately left the area. The unidentified male was never
located. Cannon was arrested and searched, but police found neither money nor drugs.
Cannon was charged with drug offenses. The trial court conducted a pretrial hearing to determine
whether the State would be permitted to offer the expert testimony of a police officer regarding the use of a
"money man" by street-level drug dealers. The proposed testimony would explain that a "money man" is used
by drug dealers to avoid the risk of being apprehended while in possession of both drugs and large sums of
money.
The trial court determined that the State could not offer the expert testimony during its direct case
because the scope of the proposed testimony was not beyond the jury's common knowledge. The trial judge also
found that the prejudicial impact of the proposed expert testimony outweighed its probative value.
The Appellate Division reversed, observing that the act of passing money to a third person would be
meaningless to jurors unless they were aware of its significance in the drug trade. It stated that expert testimony
is helpful for the jury to understand the operating methods of drug traffickers. The Court granted defendant's
motion for leave to appeal.
HELD: Expert testimony in drug prosecutions generally is to be admitted provided the trial court is satisfied
that the testimony will assist the jury in resolving material factual issues. That general rule should be tempered
by the trial court's heightened awareness that in certain circumstances the probative value of such expert
testimony might be substantially outweighed by the risk of undue prejudice.
1. Expert opinion is admissible if the general subject matter at issue, or its specific application, is one with
which an average juror might not be sufficiently familiar, or if the trial court determines that the expert testimony
would assist the jury in comprehending the evidence and determining issues of fact. (pp. 10-16)
2. The general rule in the federal courts favors admissibility of expert testimony explaining operating
methods of drug dealers in the prosecution of drug-distribution offenses. A number of state courts have applied
similar reasoning in concluding that such testimony would be likely to enhance the jury's ability to understand
the evidence adduced. Despite the general acceptance of the admissibility of such expert testimony in the
prosecution of drug cases, the federal courts have noted their apprehension about the inappropriate uses of such
testimony when it would result in material prejudice. (pp. 16-22)
3. Expert testimony that encompasses ultimate issues to be decided by the trier of fact is also authorized
under N.J.R.E. 704. In drug prosecutions, however, the risk of prejudice has prompted courts to exercise caution
in determining whether expert testimony touching on ultimate issues is admissible. In such cases, the trial court
should carefully instruct the jury in the context of the evidence about its duty to decide whether to accept or
reject the opinion of the expert witness. (pp. 22-28)
4. In resolving the Berry appeal, there can be little question that an average juror would be unfamiliar with
the finer points of drug acquisition and distribution techniques described by the police officer. Nor can there
be any doubt that the officer's testimony would assist the jury in understanding the evidence and in resolving
material factual issues. The expert's opinion on the issue of possession might have constituted an opinion that
defendant is guilty of the crime charged, and exclusion might have been warranted had the opinion been elicited
during direct testimony. The opinion was sought, however, by defense counsel, and trial errors originating with
defense counsel will not present grounds for reversal on appeal except in the most extreme cases. Based on the
record, including the expert testimony, the Court is persuaded that the jury had before it ample evidence to
support Berry's convictions. (pp. 28-30)
5. In respect of the appeal in Cannon, trial courts ordinarily are entitled to wide latitude in exercising
discretionary authority to exclude evidence because of its potentially prejudicial impact. Due to the novelty and
importance of the evidentiary issue presented here, both generally and in drug prosecutions, the Court is
compelled to intervene and order that the expert testimony be admitted. Jurors in general are totally unfamiliar
with the techniques used by street-level drug dealers, and the jury's ability to understand the trial testimony will
be enhanced by an understanding that at least a fair number of dealers use a "money man" to limit their exposure
to prosecution. The trial court's concern about the risk of prejudice can be addressed by a qualifying instruction
to the jury that conveys that it is the jury's prerogative to reject both the expert's opinion and the version of the
facts consistent with that opinion. (pp. 30-32)
The judgment of the Appellate Division in Berry is REVERSED, the convictions are reinstated, and the
matter is REMANDED to the trial court for further proceedings. In Cannon, the judgment of the Appellate
Division is AFFIRMED .
CHIEF JUSTICE WILENTZ and JUSTICES HANDLER, POLLOCK, O'HERN and GARIBALDI join
in JUSTICE STEIN's opinion. JUSTICE COLEMAN did not participate.
SUPREME COURT OF NEW JERSEY
A-15/
42 September Term 1994
STATE OF NEW JERSEY,
Plaintiff-Appellant,
v. A-15
CHARLES MARSHALL BERRY,
Defendant-Respondent.
------------------------------
STATE OF NEW JERSEY,
Plaintiff-Respondent,
v. A-42
DWAYNE CANNON,
Defendant-Appellant.
Argued May 4, 1994 -- Reargued September 27, 1994 (A-15)
Argued September 27, 1994 (A-42)
Decided May 4, 1995
On appeal from the Superior Court, Appellate Division
(State v. Berry).
On appeal from the Superior Court, Appellate Division, whose
opinion is reported at
271 N.J. Super. 391 (1994) (State v.
Cannon).
Paul H. Heinzel, Deputy Attorney General, argued the
cause for appellant State of New Jersey (Deborah T.
Poritz, Attorney General of New Jersey, attorney).
Matthew Astore, Deputy Public Defender II, argued the
cause for appellant Dwayne Cannon (Susan L. Reisner,
Acting Public Defender, attorney).
M. Virginia Barta, Assistant Deputy Public Defender,
argued the cause for respondent Charles Marshall Berry
(Susan L. Reisner, Acting Public Defender, attorney).
Jeffrey Garrigan, Assistant Prosecutor, argued the
cause for respondent State of New Jersey (Carmen
Messano, Hudson County Prosecutor, attorney).
Deborah Bartolomey, Deputy Attorney General, argued the
cause for amicus curiae, Attorney General of New Jersey
in State v. Cannon (Deborah T. Poritz, Attorney
General, attorney).
The opinion of the Court was delivered by
STEIN, J.
These appeals concern the State's practice of using expert
witnesses in drug-distribution cases to explain techniques
commonly used by drug dealers. The expert testimony typically is
offered to enhance the jury's understanding of the factual
evidence proffered by the State to prove the commission of the
offenses charged in the indictments.
In State v. Berry, the sole question presented in the
State's appeal, here by virtue of a dissent in the Appellate
Division, see Rule 2:2-1(a)(2), is whether defendant's
convictions for possession of cocaine and possession with intent
to distribute were based on sufficient evidential support in the
record. In an unpublished disposition the Appellate Division
majority reversed the conviction, holding that the State's
expert's opinion could not properly have been used "to convert
presence in a vehicle into active participation." The dissenter
below, pointing out that the State's expert had testified that
defendant had "'without a question, possessed [the drugs] for the
sole purpose of selling them,'" concluded that abundant evidence
established defendant's guilt. Although the admissibility of the
expert's testimony was not directly posed, we listed the case for
reargument, together with State v. Cannon, to afford counsel the
opportunity to address the issue of admissibility.
In Cannon, the Appellate Division in a published opinion,
271 N.J. Super. 391 (1994), reversed a pretrial ruling in a drug-distribution prosecution barring the State from introducing
expert testimony concerning distribution methods commonly used by
street-level drug dealers. We granted defendant's motion for
leave to appeal. See Rule 2:2-2.
On August 1, 1990, at approximately 3:40 p.m., James Steiger, a New Jersey State Police Officer, stopped a 1984 Buick traveling westbound on Interstate 80. The officer was parked at the Fletcher Avenue U-turn in the Borough of Fort Lee observing southbound express-lane traffic on Interstate Highway 95 and westbound traffic on Interstate Highway 80. As the 1984 Buick passed his vantage point, the officer noticed that the left portion of the front windshield was cracked and that yellow dice were hanging from the rear-view mirror. The officer stopped the car for violating N.J.S.A. 39:3-74 (requiring "unobstructed" windshield) and N.J.S.A. 39:3-75 (prohibiting "unduly fractured" windshield).
The driver, defendant Charles Marshall Berry, told the
officer his name and gave him a vehicle-registration card and an
insurance card, both of which belonged to Gracie Lyde, whom Berry
identified as his girlfriend. Berry could not, however, produce
his driver's license. Berry was "extremely nervous" and would
not look Officer Steiger "in the eye" when he spoke to him.
Moreover, Berry's "hands were trembling." As a result, Officer
Steiger asked Berry to exit the car and, after Berry complied, he
conducted a pat-down search of Berry. He then asked the
passenger in the front seat, A.C., to exit the car. While the
officer was speaking to A.C., he noticed that he had a plastic
bag in his mouth, which the officer directed him to spit out.
After he spat the bag to the ground, Officer Steiger saw that
"the plastic bag contained a yellow chunky substance [that he]
suspected to be crack cocaine." Subsequent laboratory analysis
revealed that the rock-like substance found in A.C.'s mouth was
17.90 grams (.63 ounces) of cocaine. The officer then conducted
a pat-down search of A.C. and told him to stand next to Berry in
front of the car. The officer ordered the passenger in the
backseat, L.K., out of the car and conducted a pat-down search of
L.K. The officer then arrested all three occupants for
possession of cocaine.
Officer Steiger transported defendant and his passengers to
the Totowa Barracks, where he ascertained that A.C. and L.K. were
juveniles. The officer then conducted a search incident to the
arrest of the suspects, and found a "plastic bag containing one-hundred small, clear plastic bags in [A.C.'s] left sock." He
also issued two summonses to Berry for the motor-vehicle
violations.
Berry was charged on a two-count indictment with violating
N.J.S.A. 2C:35-5a(1)b(2) (possession of cocaine with intent to
distribute) (count one), and N.J.S.A. 2C:35-10a(1) (possession of
cocaine substance) (count two). At trial, Officer Steiger and
Sergeant Michael Carlino, a member of the Bergen County Narcotics
Task Force, testified for the State. Officer Steiger testified
essentially to the facts and circumstances surrounding the
arrest. Sergeant Carlino testified that he has been with the
Bergen County Prosecutor's Office for "approximately fourteen
years, seven of which [he] spent with the Bergen County Narcotic
Task Force." He stated that he had been involved in
approximately 800 cocaine-related investigations and had made
"[h]undreds" of cocaine-related arrests. At the time of trial,
he was a supervisor with the Bergen County Narcotics Task Force
and supervised approximately thirty undercover investigators.
The trial court accepted Sergeant Carlino as an expert in
"narcotics and narcotics distribution," and Sergeant Carlino's
expert testimony was introduced without objection.
The prosecutor questioned Sergeant Carlino about the
distribution of cocaine in the context of a hypothetical set of
facts that mirrored the facts and circumstances described in
Officer Steiger's testimony. Sergeant Carlino testified that the
quantity of cocaine described would typically be broken down into
powder form, diluted, and sold in packets ranging in weight from
one-tenth of a gram to one-half ounce. He stated that New Jersey
drug dealers involved with large quantities of cocaine -- ten
ounces or more -- would probably attempt to purchase the drugs in
New York City because the price was lower, and that dealers
distributing smaller quantities would buy their cocaine from New
Jersey suppliers. Sergeant Carlino testified that the quantity
of cocaine described by Officer Steiger could be purchased in New
York City for approximately $900, and if that cocaine were broken
down and sold in New Jersey in one-tenth of a gram packets its
value would be approximately $1800. Sergeant Carlino stated that
zip-lock plastic bags of the type found in A.C.'s sock are used
to package cocaine for resale as crack.
Sergeant Carlino was asked about the significance, in the
hypothesized facts, of there being three occupants in the
vehicle, two of whom were juveniles. He testified that drug
dealers traveling to New York City to purchase drugs often are
accompanied by one or two associates for reasons of safety, and
he stated that juveniles are often used as "mules" to carry the
drugs so that in the event of apprehension the dealer can avoid
serious criminal charges. He testified that juveniles frequently
serve as "runners" or "steerers" for drug distributors, but
rarely can afford to spend as much as $900 to purchase a large
quantity of cocaine. Sergeant Carlino also expressed the opinion
that based on the value and high quality of the cocaine, "there's
no question that this cocaine was possessed for the sole purpose
of resale for distribution."
On cross-examination, defense counsel asked Sergeant Carlino
whether "Charles Berry possessed that cocaine with the intent to
distribute." The prosecutor objected to that question,
contending that it would be improper for Sergeant Carlino to
testify about a legal conclusion. On recross-examination,
defense counsel again asked whether "with any degree of certainty
* * * any particular person possessed those drugs with the intent
to distribute?" Sergeant Carlino responded that "all three
defendants in the vehicle, without a question, possessed these
items for the sole purpose of selling them, repackaging this
cocaine into these packets for resale." He then stated, "If
you're asking my opinion as to your client or the other two
individuals, it was my opinion that they all possessed this
cocaine with the intent to resell it." On redirect-examination,
"[t]o insure that the question [was] properly placed before the
jury," the prosecutor asked Sergeant Carlino whether it was his
"opinion that the adult-male driver in the hypothetical question
possessed the cocaine in question with the intent to distribute."
He answered that he believed that that driver possessed the
cocaine with the intent to distribute.
The jury returned a guilty verdict on both counts. The
trial court sentenced Berry to ten-years imprisonment on count
one, and merged count two into count one. The Appellate Division
reversed Berry's convictions, concluding that the evidence was
insufficient to sustain the jury's verdict, whereas the
dissenting member was of the view that the verdict was amply
supported by the State's proofs.
Because this appeal concerns a pre-trial evidentiary ruling by the trial court, we summarize the facts primarily on the basis of a proffer by the Assistant Prosecutor concerning the testimony that he expected to elicit at trial from Sergeant Phil Zacche of the Jersey City Police Department. Members of the Jersey City Police Department Narcotics Task Force established surveillance of the intersection of Wilkerson Avenue and Martin Luther King Drive in Jersey City. Sergeant Zacche observed defendant Dwayne Cannon standing on the northwest corner of that intersection. He saw codefendant Ronald McQuarters approach the corner on a bicycle and engage in a brief conversation with Cannon. They proceeded west on Wilkerson Avenue a short distance, whereupon McQuarters handed Cannon money for what appeared to be several vials of cocaine. McQuarters left the area, proceeding south on Martin Luther King Drive. Sergeant Zacche radioed McQuarters's description and route to other police officers, who then stopped and searched him. The search revealed four vials of cocaine.
Sergeant Zacche then observed Cannon hand the money he had received from McQuarters to an unidentified male wearing a shiny green jacket with a black hood and jeans, who immediately left the area proceeding south on Martin Luther King Drive. Sergeant
Zacche radioed that person's description and route to the other
task-force members, but he was never located. Cannon was
subsequently arrested and searched, but the police found neither
money nor drugs.
Cannon was charged with possession of cocaine, contrary to
N.J.S.A. 2C:35-10a(1) (count one); possession of cocaine with the
intent to distribute, contrary to N.J.S.A. 2C:35-5a(1) and 2C:35-5b(3) (count two); possession of cocaine within 1,000 feet of
school property with the intent to distribute, contrary to
N.J.S.A. 2C:35-5a(1) and 2C:35-7 (count three); distribution of
cocaine, contrary to N.J.S.A. 2C:35-5a(1) and 2C:35-5b(3) (count
four); and distribution of cocaine within 1,000 feet of school
property, contrary to N.J.S.A. 2C:35-5a(1) and 2C:35-7 (count
five).
During jury selection, the trial court conducted a pretrial
hearing to determine whether the State would be permitted to
offer the expert testimony of Jersey City Police Detective
Richard Vogel at Cannon's trial. The Assistant Prosecutor
explained that the State intended to elicit expert testimony
concerning techniques commonly used by street-level drug dealers,
specifically including the use of a so-called "money man" to whom
the drug dealer transfers the proceeds of drug sales. The
proposed expert testimony would explain that through the use of a
"money man" a drug dealer can avoid the risk of being apprehended
while in possession of both drugs and large sums of money,
presumably diminishing the likelihood of being charged with
serious drug-distribution offenses. The Assistant Prosecutor
contended that the proposed expert testimony would provide a
frame of reference that would enhance the jury's ability to
understand the testimony to be offered by Sergeant Zacche, the
officer who had observed the drug transaction.
The trial court determined that the State could not offer
the expert testimony during its direct case, noting that the
scope of the expert's testimony was not beyond the jury's common
fund of knowledge. The trial court also observed that the
prejudicial impact of the proposed expert testimony outweighed
its probative value. Finally, the trial court noted that the
testimony might be admissible as rebuttal evidence in the event
defendant offered evidence that provided an independent
explanation for the transfer of money to the unidentified third
person.
The Appellate Division reversed, observing that "[t]he act
of passing money by defendant to a third person would be
meaningless to a jury unless they were aware of its significance
in the drug trade. Expert testimony is helpful for the jury to
understand the 'modus operandi' of drug traffickers." 271
N.J. Super. at 396.
Our discussion of the permissible uses of expert testimony in drug distribution cases starts with N.J.R.E. 702, which follows verbatim Fed. R. Evid. 702, and 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 State v. Kelly,
97 N.J. 178 (1984), focusing on the first sentence of former Evidence
Rule 56(2) (which, except for minor language changes, was
identical with N.J.R.E. 702), we set forth three basic
requirements for 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 field testified to
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 offer the intended
testimony.
At the outset, we confront the suggestion advanced by some commentators that the standard of admissibility of expert testimony described in Kelly, supra, is narrower than that contemplated by Fed. R. Evid. 702, which, like its New Jersey counterpart, limits admissibility only to expert testimony that "will assist the trier of fact to understand the evidence or to determine a fact in issue." See 3 Jack B. Weinstein & Margaret A. Berger, Weinstein's Evidence ¶ 7.02[02], at 702-15 (1988) ("Must a court exclude expert testimony if the subject is within the comprehension of the average juror? Such a test is incompatible with the standard of helpfulness expressed in Rule 702."); Deon J. Nossel, Note, The Admissibility of Ultimate
Issue Expert Testimony by Law Enforcement Officers in Criminal
Trials,
93 Colum. L. Rev. 231, 234 (1993) ("Rule 702's standard
of admissibility is significantly more liberal than that of the
common law, which permitted expert testimony only regarding
subjects 'beyond the ken of the jury' or 'not within the common
knowledge of the average layman.'"). In our view, the evolution
of Evidence Rule 56(2), the predecessor to N.J.R.E. 702, as well
as our case law, demonstrate that the "helpfulness" standard of
Fed. R. Evid. 702 is imbedded in our own jurisprudence concerning
admissibility of expert testimony.
Prior to the 1981 amendment to Evidence Rule 56(2) (which
became effective July 1, 1982), the Rule contained no standard
for admissibility of expert testimony. It then provided:
(2) If the witness is testifying as an
expert, testimony of the witness in the form
of opinions or inferences is limited to such
opinions as the judge finds are (a) based
primarily on facts, data or other expert
opinion established by evidence at the trial
and (b) within the scope of the special
knowledge, skill, experience or training
possessed by the witness.
The Report of the New Jersey Supreme Court Committee on Evidence,
106-07 (1963) explains the omission of a standard for
admissibility:
The Rule does not describe, as the Model Code
rule did, when an expert testifies as such
and who is qualified to testify as an expert.
Model Code Rule 402 provided: "A witness is
an expert witness and is qualified to give
expert testimony if the judge finds that to
perceive, know or understand the matter
concerning which the witness is to testify
requires special knowledge, skill, experience
or training, and that the witness has the
requisite special knowledge, skill,
experience or training." This appears to be
such well-settled law that there is no need
to state it in Rule 56.
The language that limits admissibility to expert testimony
that "will assist the trier of fact to understand the evidence or
determine a fact an issue" originated with Fed. R. Evid. 702 and
was incorporated into Evidence Rule 56(2) by the 1981 amendment.
See State v. Gunter,
231 N.J. Super. 34, 41 (App. Div.), certif.
denied,
117 N.J. 80-81 (1989). However, the standard of
helpfulness that we imported from the Federal Rule had been
"widely accepted by our courts even before the rule amendment."
Biunno, Current N.J. Rules of Evidence, comment 1 on N.J.R.E. 702
(1994-95). As this Court noted in Rempfer v. Deerfield Packing
Corp.,
4 N.J. 135 (1950):
Was the expert testimony concerning
profits admissible or did it encroach upon
the function of the trial jury? The true
test of admissibility of such testimony is
not whether the subject matter is common or
uncommon or whether many persons or few have
knowledge of the matter; but it is whether
the witnesses offered as experts have
peculiar knowledge or experience not common
to the world which renders their opinions
founded on such knowledge or experience any
aid to the court or jury in determining the
questions at issue.
Testing the admissibility of expert testimony by focusing not only on the jury's comprehension of the subject matter but also on whether the specific proffered testimony will aid the jury in resolving factual issues has been a recurring theme in our cases.
See State v. Odom,
116 N.J. 65, 70 (1989); State v. Zola,
112 N.J. 384, 414 (1988), cert. denied,
489 U.S. 1022,
109 S. Ct. 1146,
103 L. Ed.2d 205 (1989); Kelly, supra, 97 N.J. at 204
(1984); Butler v. Acme Markets, Inc.,
89 N.J. 270, 283 (1982);
Gunter, supra, 231 N.J. Super. at 47; Nesta v. Meyer,
100 N.J. Super. 434, 442 (App. Div. 1968). To the extent that there
is a perceived need to bridge the gap, if any, between the
standards that test expert-testimony admissibility on whether the
subject is "beyond the ken of the average juror," Kelly, supra,
97 N.J. at 208, or on whether the testimony will "assist the
trier of fact * * * to determine a fact in issue," N.J.R.E. 702,
Justice Handler has provided a lucid reconciliation:
The test for determining whether expert
testimony can be offered is normally phrased
in terms of whether the particular subject
matter is beyond the understanding of the
ordinary person. Sometimes it is asked in
terms of whether expert testimony will assist
the average juror to understand the evidence
that has been presented.
Disputes over admissibility are
particularly sharp when expert testimony is
offered to interpret matters that could be
considered commonplace or conduct that could
be accounted for commonsensically. When we
are dealing with life's everyday experiences,
it is not always easy to perceive why it is
necessary to have an expert to explain things
for us.
In each of these cases, we are presented with individuals engaged in recurrent forms of human behavior--a wife who kills her husband out of fear and hostility, a child sexually molested by an elderly adult
relative, natural parents desperately seeking
exclusive control over their child. Yet, in
each case we were invited to believe that our
understanding of these events was inaccurate
or too simplistic, that true insight into
what really happened was too elusive. These
cases point out the deceptiveness of the
ordinary; they illustrate how the familiar,
when probed, can become esoteric, the
commonplace, unusual, and the obvious,
obscure. Each is a case in which there is
more, considerably more, than meets the eye.
In these situations experts are called
on to explain things that are suddenly or
surprisingly or seemingly made complicated
and profound; experts are needed to give us
understanding and insight because
conventional wisdom no longer serves.
However, when the underlying knowledge of
such matters is genuinely unsettled, when the
experts themselves are in disarray, we may
question whether the decision in a given case
informed by the opinions of experts will
reflect the truth. Experts can hold justice
hostage.
[Alan B. Handler, The Judicial Pursuit of
Knowledge: Truth And/Or Justice,
41 Rutgers
L. Rev. 1, 5, 8, 10-11 (1988) (footnote
omitted).]
Thus, expert opinion is admissible if the general subject matter at issue, or its specific application, is one with which an average juror might not be sufficiently familiar, or if the trial court determines that the expert testimony would "assist the jury in comprehending the evidence and determining issues of fact." Odom, supra, 116 N.J. at 70. The proposed expert witness must be adequately qualified and possess sufficient knowledge and experience to express an opinion and explain its basis to the jury. Id. at 71; Kelly, supra, 97 N.J. at 208. Ordinarily, the necessity for and admissibility of expert testimony are matters
to be determined within the sound exercise of discretion by the
trial court. Zola, supra, 112 N.J. at 414.
Reported opinions in New Jersey have not previously
addressed the specific question whether expert testimony
explaining the modus operandi of drug dealers should be
admissible in the prosecution of drug-distribution offenses. The
general rule in the federal courts favors admissibility of such
evidence. "Federal courts often permit experts to testify on
narcotics operations because jurors are commonly unfamiliar with
the methods by which drug dealers attempt to conceal their
activities." United States v. Dunn,
846 F.2d 761, 763 (D.C. Cir.
1988). See, e.g., United States v. Boney,
977 F.2d 624, 628-29
(D.C. Cir. 1992) (holding admissible expert testimony that
identified "seller," "runner," and "holder" in hypothetical drug
transaction that replicated government's trial proof); United
States v. Roldan-Zapata,
916 F.2d 795, 804-05 (2d Cir. 1990)
(upholding admissibility of expert testimony concerning drug-related function of ledger, shoe boxes, and other items seized
from defendant's apartment and explaining narcotics dealers' use
of "beepers" to avoid detection), cert. denied,
499 U.S. 940,
111 S. Ct. 1397,
113 L. Ed.2d 453 (1991); United States v. Campino,
890 F.2d 588, 593 (2d Cir. 1989) (upholding trial court's ruling
admitting expert testimony concerning drug dealers' use of
electronic surveillance equipment similar to that found at
defendants' apartment and testimony that seized notebooks
contained records of amounts owed by customers for cocaine
transactions), cert. denied, 494 U.S. 1068, 110 S. Ct. 1787, 108 L. Ed.2d 788 (1990); United States v. Tutino, 883 F.2d 1125, 1133-34 (2d Cir. 1989) (holding admissible expert witness testimony generally describing heroin-distribution methods and interpreting organized-crime terminology heard on tape-recordings introduced in evidence), cert. denied, 493 U.S. 1081, 110 S. Ct. 1139, 107 L. Ed.2d 1044 (1990); United States v. Diaz, 878 F.2d 608, 616-18 (2d Cir.) (sustaining admission of expert-witness testimony concerning characteristics of narcotics "stash pad" and providing interpretation of financial records seized at residence used for drug distribution), cert. denied, 493 U.S. 993, 110 S. Ct. 543, 107 L. Ed.2d 540 (1989); Dunn, supra, 846 F. 2d at 762-63 (sustaining trial court's admission of expert testimony explaining that vials, wax-paper bags, I-beam scales, measuring spoons, and manitol were customarily used by narcotics dealers for drug-distribution purposes); United States v. Espinosa, 827 F.2d 604, 611-13 (9th Cir. 1987) (upholding admissibility of expert testimony that apartment rented by another was used by defendant as narcotics "stash pad," that ledgers found in apartment contained names of cocaine customers, and that exchange of packages witnessed by police officers constituted delivery of narcotics for money), cert. denied, 485 U.S. 968, 108 S. Ct. 1243, 99 L. Ed.2d 441 (1988); United States v. Resto, 824 F.2d 210, 211-12 (2d Cir. 1987) (upholding sufficiency of evidence to support defendant's conviction for aiding sale of narcotics, including expert testimony explaining that "steerer" typically
stands short distance from dealer to solicit and screen potential
buyers and guide them to dealer); United States v. Cruz,
797 F.2d 90, 96 (2d Cir. 1986) (sustaining admissibility of expert
testimony concerning practice of exchanging food stamps for
narcotics); United States v. Khan,
787 F.2d 28, 34 (2d Cir. 1986)
(upholding trial court's admission of expert testimony concerning
customs of narcotics dealers in Pakistan, including testimony
about heroin prices and transfers of heroin with payment
deferred); United States v. Daniels,
723 F.2d 31, 32-33 (8th Cir.
1983) (holding admissible expert-witness testimony that drug
dealers commonly register cars and apartments in names of female
friends to conceal narcotics activities); United States v.
Pugliese,
712 F.2d 1574, 1578-82 (2d Cir. 1983) (sustaining
admission of expert testimony concerning quantity and purity of
heroin used by addicts in context of defendants' contention that
heroin seized was imported for personal use and not for
distribution); United States v. Fleishman,
684 F.2d 1329, 1335-36
(9th Cir.) (holding admissible expert testimony that defendant's
actions were consistent with role of "lookout" in drug
distribution conspiracy), cert. denied,
459 U.S. 1044,
103 S. Ct. 464,
74 L. Ed.2d 614 (1982); United States v. Maher,
645 F.2d 780, 783-84 (9th Cir. 1981) (upholding admission of expert
testimony comparing defendant's activities to those of persons
conducting counter-surveillance while transporting drugs).
A number of state courts have applied similar reasoning in
concluding that expert testimony concerning the modus operandi of
drug dealers would be likely to enhance the jury's ability to
understand the evidence adduced. See, e.g., State v. Salazar,
557 P.2d 552, 557 (Ariz. Ct. App. 1976) (holding admissible
expert testimony concerning counter-surveillance techniques
commonly used by narcotics dealers, specifically including
practice of using vehicle to observe in advance area where
distribution was intended to occur); State v. Vilalastra,
540 A.2d 42, 46-48 (Conn. 1988) (holding admissible police officer's
expert testimony that seized cocaine of eighty-three percent
purity would be "cut" with lactose to achieve lesser purity prior
to street-level distribution); State v. Avila,
353 A.2d 776, 780-81 (Conn. 1974) (upholding as admissible state toxicologist's
testimony that quantity and purity of seized heroin, if diluted
and packaged, was sufficient to supply 22,400 bags of heroin
appropriate for street-level distribution); Benefield v. State,
232 S.E.2d 89, 93-94 (Ga. Ct. App. 1976) (holding admissible
police officer's expert testimony that narcotics dealers often
use intermediary in making delivery to buyer under mistaken
assumption that intermediary would insulate dealers from criminal
liability); State v. Olsen,
315 N.W.2d 1, 7 (Iowa 1982)
(sustaining admissibility of expert testimony that quantity of
marijuana found in defendant's possession could be diluted and
profitably distributed to others); Butler v. State,
313 A.2d 554,
560 (Md. Ct. Spec. App. 1974) (sustaining admissibility of police
officers' expert testimony concerning use of "stash house" by
narcotics dealers to store drugs for future distribution).
Despite the general acceptance of the admissibility of modus
operandi expert testimony in the prosecution of drug cases, the
federal courts have noted their apprehension about the
inappropriate uses of such testimony. In United States v.
Castillo,
924 F.2d 1227 (1991), the Court of Appeals for the
Second Circuit reversed the defendants' convictions for carrying
a firearm during commission of a drug-trafficking offense in
violation of
18 U.S.C.A.
§924(c), on the ground that the
improper admission of expert testimony had materially prejudiced
the jury's verdict. The government's main witness, an undercover
narcotics officer, testified that after he had purchased cocaine
from the defendants, they had forced him to ingest some of the
cocaine by threatening him with what had appeared to be a
handgun. When police arrested the defendants minutes later,
neither defendant possessed a firearm and no weapon was found in
the apartment. At trial, an experienced narcotics detective
testified as an expert about the techniques of New York drug
dealers, and specifically testified about numerous occasions when
drug dealers had used guns to make potential customers sniff
cocaine, for the purpose of detecting police officers making
undercover buys. Reversing the handgun-possession convictions
because of the prejudicial effect of the expert testimony, the
Court stated:
[W]e take serious issue with the Government's
use of an expert witness to propound the
impermissible theory that appellants' guilt
could be inferred from the behavior of
unrelated persons. We conclude that the
government's misuse of what was, in any
event, improperly admitted testimony, could
only have had a substantial and injurious
effect on the jury's count four verdicts.
The firearm count was perhaps perceived as
weak from the case's inception--no gun had
ever been recovered, despite searches of
appellants' persons, the apartment, the area
outside the apartment windows and the
vicinity of the arrest. . . . The jury's
notes to the Judge during deliberations,
manifesting their recognition that, in fact,
the firearm count was troubling, are telling.
. . . In view of the evidence on the count,
the jury's obvious struggle, and the absence
of any curative instruction from the court,
we hold that the government's misuse of
Santiago's testimony by its introduction, and
heavy reliance on it in summation, improperly
tipped the balance against appellants on the
firearm charge.
Similarly, in United States v. Cruz, 981 F.2d 659 (2d Cir. 1992), the court of appeals reversed defendant Bonifacio's conviction for various drug-distribution offenses on the ground that expert testimony about the role of brokers in facilitating drug purchases by upstate buyers from dealers in the Washington Heights area of New York City had been used improperly by the government in the presentation of its case. Bonifacio was implicated in the transactions by the testimony of defendant LaBoy, an Albany drug dealer, who testified that Bonifacio had on five occasions accompanied him to New York and made arrangements for LaBoy to purchase cocaine from Washington Heights dealers. Bonifacio's defense was that he had never been present at or arranged drug transactions for LaBoy, and that LaBoy had falsely accused him to obtain leniency from the government. The government's expert testified that drug dealers from upstate New
York intending to purchase drugs from a dealer in Washington
Heights typically relied on a broker or middleman who deals
directly with the dealer. The expert testified that the broker
generally arranges for delivery of the drugs to the buyer at a
neutral location to protect the identity of both seller and
buyer. In summation, the prosecutor argued that LaBoy's direct
testimony about Bonifacio's role in arranging for his New York
City drug purchases paralleled the usual procedure outlined by
the government's expert witness. Reversing the defendant's
conviction, the court of appeals noted that "the dispositive
factual issue was whether Bonifacio was present at the drug
transactions," and that accordingly "[t]he role of a broker * * *
was simply not an issue that the parties disputed." Id. at 662.
The court concluded that the government had adduced the expert
testimony for the "impermissible and prejudicial" purpose of
enhancing the credibility of LaBoy's version of the facts:
We reaffirm here the principle that the
credibility of a fact-witness may not be
bolstered by arguing that the witness's
version of events is consistent with an
expert's description of patterns of criminal
conduct, at least where the witness's version
is not attacked as improbable or ambiguous
evidence of such conduct.
N.J.R.E. 704, like its counterpart Fed. R. Evid. 704(a), also authorizes the admission of expert testimony that encompasses ultimate issues to be decided by the trier of fact, Odom, supra, 116 N.J. at 77-81 (interpreting predecessor to N.J.R.E. 704). Concerning the admissibility of expert testimony
addressing an ultimate issue, we noted in Odom that "the dominant
authority throughout the country has ruled that an expert witness
may testify that a defendant possessed a controlled dangerous
substance with the intent to distribute it, even if the opinion
is expressed in the language of the statutory offense." Id. at
79. However, a number of federal and state courts have expressed
concern that under certain circumstances expert testimony in drug
cases embracing ultimate issues might be so prejudicial as to
require exclusion. The evidentiary rules allowing admission of
expert testimony on ultimate issues repudiate the common-law rule
precluding such testimony because it invaded the jury's province.
See Nossel, supra,
93 Colum. L. Rev. at 235. Although
admissible, such testimony may be excluded if its probative value
is substantially outweighed by the risk of undue prejudice.
N.J.R.E. 403(a). See Fed. R. Evid. 403. In drug prosecutions,
that risk of prejudice has prompted courts to exercise caution in
determining whether expert testimony touching on ultimate issues
properly was admitted at trial.
In United States v. Young,
745 F.2d 733 (2d Cir. 1984),
cert. denied,
470 U.S. 1084,
105 S. Ct. 1842,
85 L. Ed.2d 142
(1985), the convictions of all but one defendant on charges of
conspiracy to distribute heroin were sustained, as was the
admissibility at trial of expert testimony, including the expert
testimony of one of the investigating officers that an exchange
of handbags that he had observed at a local hotel constituted a
sale of drugs. Judge Newman, concurring, explained his concerns
about the use of such testimony:
I do not doubt that an experienced narcotics
agent has the requisite knowledge to assist a
jury by explaining "the clandestine manner in
which drugs are bought and sold[.]" But I
question whether an expert's opinion that the
events he observes constitute a drug
transaction provides very much, if any,
assistance to a jury, beyond whatever
inference is available to be drawn by the
jury from all the evidence. . . .
Even if admissible under Rule 702,
opinion testimony is still subject to
exclusion under Rule 403 "if its probative
value is substantially outweighed by the
danger of unfair prejudice." Whatever slight
probative value arises from a narcotics
expert's personal opinion that an observed
transaction involved a sale of drugs must be
carefully weighed against the distinct risk
of prejudice. The "aura of special
reliability and trustworthiness" surrounding
expert testimony, which ought to caution its
use, especially when offered by the
prosecution in criminal cases, poses a
special risk in a case of this sort. That
risk arises because the jury may infer that
the agent's opinion about the criminal nature
of the defendant's activity is based on
knowledge of the defendant beyond the
evidence at trial. The risk is increased
when the opinion is given by "the very
officers who were in charge of the
investigation[.]"
Similarly, in United States v. Brown, 776 F.2d 397 (2d Cir. 1985), cert. denied, 475 U.S. 1141, 106 S. Ct. 1793, 90 L. Ed.2d 339 (1986), the investigating officer was permitted to testify as an expert that street drug sales in Harlem generally involved the use of a "steerer," whose function it was to determine if a prospective buyer was a genuine customer or an undercover police
officer, and also to express the opinion that one of the
defendants (Brown) had functioned as a "steerer" in the drug
transaction that was the subject of the prosecution. Judge
Friendly's opinion for the court concluded that expert testimony
about the function of a steerer was properly admitted. Id. at
400. Although observing that adequate evidence to sustain
defendant Brown's conviction existed apart from the expert's
testimony, the court expressed its concern about the
admissibility of expert testimony describing Brown as a steerer:
The admission of Grimball's opinion
testimony that Brown was fulfilling the role
of a steerer raises a closer question. We
recognize that Rule 704(a) * * * abolished
the antiquated rule, more frequently honored
in the breach than the observance, excluding
expert testimony "because it embraces an
ultimate issue to be decided by the trier of
fact." However, there is something rather
offensive in allowing an investigating
officer to testify not simply that a certain
pattern of conduct is often found in
narcotics cases, leaving it for the jury to
determine whether the defendant's conduct
fits the pattern, but also that such conduct
fitted that pattern, at least when other
inferences could have been drawn not
unreasonably although perhaps not as
reasonably as that to which the expert
testified. * * * Even though the testimony is
not barred by F.R.E. 704(b), district judges
should heed the Advisory Committee's Note to
Rule 704:
The abolition of the ultimate issue rule does not lower the bars so as to admit all opinions. Under Rules 701 and 702, opinions must be helpful to the trier of fact, and Rule 403 provides for exclusion of evidence which wastes time. These provisions afford ample assurances against the admission of opinions which would merely tell the jury
what result to reach, somewhat in
the manner of the oath-helpers of
an earlier day.
We would thus agree with Judge Newman's
precautionary observations about the
admission of such testimony in United States
v. Young,
745 F.2d 733, 765-66 (
2 Cir. 1984)
(Newman, J., concurring), cert. denied, ___
U.S. ___,
105 S. Ct. 1842,
85 L. Ed.2d 142
(1985), which we quote in the margin, and
commend this for consideration by district
judges.
See also United States v. Boissoneault, 926 F.2d 230, 233 (2d Cir. 1991) ("We have repeatedly expressed our discomfort with expert testimony in narcotics cases that not only describes the significance of certain conduct or physical evidence in general, but also draws conclusions as to the significance of that conduct or evidence in the particular case."); United States v. Jones, 913 F.2d 174, 177 (4th Cir. 1990) (finding error in admission of expert testimony that concluded that because defendant fit profile of drug courier he therefore intended to distribute drugs in his possession), cert. denied, 498 U.S. 1052, 111 S. Ct. 766, 112 L. Ed.2d 785 (1991); United States v. Quigley, 890 F.2d 1019, 1023-24 (8th Cir. 1989) (same), cert. denied, 493 U.S. 1091, 110 S. Ct. 1163, 107 L. Ed.2d 1066 (1990); Vilalastra, supra, 540 A. 2d at 47-48 (finding error in admission of expert testimony that defendant possessed illegal drugs for sale rather than consumption); State v. Ogg, 243 N.W.2d 620, 621 (Iowa 1976) (finding error in admission of expert testimony that quantity of drugs possessed by defendant far exceeded quantity that "one
might possess for personal use"); State v. Wheeler,
416 So.2d 78, 81-82 (La. 1982) (reversing defendant's conviction because of
admission of police officer's expert opinion that defendant was
engaged in distribution of marijuana).
We also note that a number of courts, in reviewing the
admissibility of expert testimony in drug prosecutions, endorse
the use of limiting instructions that impress on the jury its
right to reject the opinion of an expert witness. See, e.g.,
Espinosa, supra, 827 F.
2d at 613; United States v. Nersesian,
824 F.2d 1294, 1309 (2d Cir.), cert. denied,
484 U.S. 957,
108 S. Ct. 355,
98 L. Ed.2d 380 (1987); Young, supra, 745 F.
2d at 761
(Newman, J., concurring); Daniels, supra, 723 F.
2d at 33; Odom,
supra, 116 N.J. at 82. Our model jury charge incorporates a
similar warning. Model Jury Charges (Criminal), Expert Testimony
(Apr. 18, 1977). In such cases, especially where the record
includes both an innocent explanation for defendant's conduct as
well as an expert witness's incriminating opinion about the same
conduct, the trial court should carefully instruct the jury in
the context of the evidence about its duty to decide whether to
accept or reject the opinion of the expert witness.
Based on the prevailing authorities, and our own sense of
the usefulness of expert testimony in drug prosecutions, we are
persuaded that such testimony generally is to be admitted
provided the trial court is satisfied that the testimony will
assist the jury in resolving material factual issues. That
general rule of admissibility, however, should be tempered by the
trial court's heightened awareness that in certain circumstances
the probative value of such expert testimony might be
substantially outweighed by the risk of undue prejudice. That
risk can be significant if the expert witness is one of the
investigating officers and also offers an opinion on an ultimate
issue in the case.
In resolving the Berry appeal, we address two issues. The primary question, whether the evidence was sufficient to sustain Berry's convictions for possession of cocaine and possession with intent to distribute, divided the Appellate Division panel, the majority concluding that the proofs were insufficient. However, we first consider the admissibility of the expert testimony, an issue not raised at trial but within the scope of the questions addressed on reargument before us.
We regard Sergeant Carlino's direct testimony essentially as modus operandi expert testimony offered to assist the jury's understanding of techniques used by some New Jersey drug dealers in acquiring cocaine in New York City for distribution in this State. The specific facts included in Carlino's testimony, about which the jury undoubtedly was uninformed, concerned the availability of cocaine at a lower cost in New York City, the street value of the cocaine in question if distributed in New Jersey, the purpose for which drug dealers use zip-lock plastic bags of the type found in A.C.'s sock, and the reasons why
drug dealers use juveniles as "mules" to carry drugs on their
person in the course of transport from New York City to New
Jersey. There can be little question that an average juror would
be unfamiliar with those finer points of drug acquisition and
distribution techniques. Nor can there be any doubt that
Sergeant Carlino's direct testimony would assist the jury in
understanding the evidence and in resolving material factual
issues. Absent the expert testimony, the jury might not
adequately have appreciated the possibility that the cocaine and
plastic bags possessed by the juvenile in the front seat were
being held for Berry. Accordingly, if that issue were presented
to the trial court, a ruling admitting Sergeant Carlino's direct
testimony would have been entirely consistent with N.J.R.E. 702
and with the extensive body of case law holding admissible modus
operandi expert testimony in drug prosecutions. Supra at ___
(slip op. at 16-19).
We note that Sergeant Carlino was asked on recross-examination whether "with any degree of certainty * * * any
particular person possessed those drugs with the intent to
distribute?" He responded that "all three defendants in the
vehicle, without question, possessed these items for the sole
purpose of selling them, repackaging this cocaine into these
packets for resale." Sergeant Carlino added that "[i]f you're
asking my opinion as to your client or the other two individuals,
it was my opinion that they all possess this cocaine with the
intent to resell it." If the same question and response were
asked and elicited during direct testimony, the response might
well have constituted an expression of opinion by the expert that
defendant is guilty of the crime charged, see Odom, supra, 116
N.J. at 80, and exclusion also might have been warranted because
of the substantial risk of prejudice. N.J.R.E. 403. The point
need not concern us, however, because except in the most extreme
cases trial errors originating with defense counsel will not
present grounds for reversal on appeal. See State v. Marshall,
123 N.J. 1, 93 (1991); State v. Buonadonna,
122 N.J. 22, 44
(1991); State v. Ramseur,
106 N.J. 123, 281-82 (1987); State v.
Pontery,
19 N.J. 457, 471 (1955).
Based on the state of the record, including Sergeant
Carlino's expert testimony elicited during both direct- and
recross-examination, we are persuaded that the jury had before it
ample evidence to support defendant's conviction. Defendant's
apparent nervousness when stopped, his lack of a driver's license
or other identification, the large quantity of cocaine possessed
by the juvenile in the front seat, combined with Sergeant
Carlino's undisputed expert testimony were sufficient to support
the jury's conclusion that defendant constructively had possessed
the cocaine possessed by a juvenile in the front seat of a car
driven by defendant, as well as the verdict that defendant was
guilty of possession of cocaine and possession with intent to
distribute.
The narrow issue presented by the Cannon appeal concerns the
admissibility of modus operandi expert testimony intended to
describe the common practice of street level drug dealers using a
so-called "money man" to whom the drug dealer passes the money
received from drug sales. The proposed testimony in Cannon would
include the explanation that drug dealers who use a "money man"
do so believing that that technique diminishes the dealer's risk
of being charged with serious drug offenses, the dealer having
avoided the possibility of being apprehended with both drugs and
money. The trial court excluded the testimony on the assumption
that the jury, as a matter of common knowledge, could have
inferred from the direct testimony that the proceeds of the drug
sale had been handed to an accomplice of defendant. The trial
court also was concerned that the prejudicial impact of the
testimony substantially outweighed its probative value.
Although trial courts ordinarily are entitled to wide
latitude in exercising discretionary authority to exclude
evidence because of its potentially prejudicial impact, State v.
Carter,
91 N.J. 86, 106 (1982), the novelty and importance of the
evidentiary issue, both generally and in drug prosecutions,
compel us to intervene and order that the expert testimony be
admitted. We do not doubt that some jurors could infer from the
testimony of the fact witnesses that a nefarious relationship
might have existed between defendant and the male in the shiny
green jacket to whom defendant allegedly handed money.
Nevertheless, jurors in general are totally unfamiliar with the
techniques used by street-level drug dealers. Even if the
testimony at trial tenders an innocent explanation for the
transfer of money, the jury's ability to understand the trial
testimony and to resolve any fact issues concerning the alleged
money transfer will be enhanced by an understanding that at least
a fair number of street-level drug dealers use a "money man" to
limit their exposure to prosecution. Based on the standard we
adopt, that such testimony generally should be admitted if it
will assist the jury in resolving material factual issues, we are
fully convinced that the proposed expert testimony meets that
test. Concerning the risk of prejudice, we have no doubt that
that concern adequately can be addressed by the trial court's
qualifying instruction to the jury, framed in the context of the
specific testimony adduced at trial, that conveys to the jury its
absolute prerogative to reject both the expert's opinion and the
version of the facts consistent with that opinion, or to rely on
that opinion in resolving the material factual issues.
In Berry, we r