This is the second appeal arising from the prosecution of appellant for bank robbery and assaulting bank employees. Appellant’s first conviction was reversеd and remanded for a new trial.
United States v. Fosher,
As noted in our first opinion, the government’s case depended almost entirely upon the testimony of two eyewitnesses who placed appellant in the vicinity of the bank at the time of the robbery. The instant appeal arises from appellant’s unsuccessful attempt to introduce purportedly expert testimony on the unreliability of eyewitness identification at the second retrial. Specifically, appellant challengеs the trial court’s rejection of a written offer of proof and of a request for government funds under 18 U.S.C. § 3006A(e) to pay for preparation of a testimonial offer on thе subject of scientific evidence relating to perception and memory of eyewitnesses.
See United States v. Fosher,
We begin with thе issue of admissibility and with the fundamental proposition that the propriety of receiving expert testimony rests within the sound discretion of the trial court.
Salem v. United States Lines Co.,
First, the written offer of proof did not make clear the relationship between the scientific evidence offered and the specific testimony of the eyewitnesses. Rather, the offer proclaimed that the exрert “will not comment at all . . on the testimony of any named witness in this or any other trial.” Although the offer also represented that the expert would not expound in general on thе unreliability of eyewitness testimony but would rather confine his recitation to such scientific facts as limited perception given limited opportunity to observe, rate of mеmory decay, and the source of memory given limited opportunity to ob *383 serve followed by review of mug shots, the offer never explained how the expert’s information wоuld help the jury analyze the particular witnesses’ ability to perceive and remember. In short, the offer supported the trial court’s discretionary conclusion that the tеstimony would have limited, if any, relevance.
Second, the offer did not make clear that the testimony, even if relevant to the particular witnesses involved, would be based upon a mode of scientific analysis that meets any of the standards of reliability applicable to scientific evidence.
See Frye v. United States,
In the same vein, we are not troubled by appellant’s arguments that F.R. Evid. 702 required admission of the expert testimony because it could “assist” the trier of fact. We recognize that the Advisory Committee’s Note accompanying Rule 702 suggests that science will “assist” the jury so long as the untrained layman would not be able “to the best рossible degree” to determine the issue by himself.
See
3 Weinstein,
supra,
at 702-2. Admittedly, lay jurors may not have the best possible knowledge of the organic and behavioral mechanisms of perception and memory. But to be a proper subject of expert testimony, proof offered to add to their knowledge must present them with a system of analysis that the court, in its discrеtion, can find reasonably likely to add to common understanding of the particular issue before the jury. We are satisfied that the trial court was within its discretion when it found the offer in this case neither sufficiently focussed on the issue nor sufficiently beyond the ken of lay jurors to satisfy Rule 702.
See United States v. Amaral,
Quite apart from questions of limited relevance and reliability, the trial court also feared that the proffered expert testimony would create a substantial danger of undue prejudice and confusion because of its aura of special reliability and trustworthiness. Other cоurts have expressed the same concern about just this sort of expert testimony.
See United States v. Brown,
This case is further complicated by the trial court’s denial of appellant’s request for government funds to support a testimonial elabоration of his offer of proof. Such an elaboration might have cured some of the problems of reliability that we think supported the trial court’s conclusion that the jury wоuld not be assisted by the expert. Nevertheless, we think the trial court was entitled to rely upon the representations made in the written offer that the expert would not analyze the testimony of the specific eyewitnesses involved in the case. Moreover, the overall thrust of the written offer emphasized general testimony about the type of perception and memory involved in the case and did not intimate that further development of the offer would make clear how the expert would help the jury analyze the' issues in the case. Given the additional discretion to consider the balance of prejudice and probative value, we cannot say that the trial court abused its discretion by deciding to forego further development of appellant’s offer of proof. Further, because the appellant sought Criminal Justice Act funds solely to develop expert testimony, if the exclusion of the expert evidence was within the discretion of the court, then the court clearly did not abuse its discretion in refusing to аuthorize funds.
2
United States v. Penick,
Affirmed.
Notes
. We read the trial court’s statement that the expert testimony would “invade the province of the jury” as reflecting its conclusion that the proffered science could not add to common sense evaluation. Contrary to appellant’s argument, we do not read the trial court’s statement as transgressing the spirit of F.R.Evid. 704. Rule 704 allows an еxpert to testify about specific facts in issue, and the Advisory Committee’s Note on the Rule rejects former doctrine which excluded expert testimony on so-called ultimate issues of fact. See 3 Weinstein, supra, at 704-1. In saying that the expert would invade the province of the jury, we think the trial court was stating that the issue was not a proper subject of expert testimony under F.R. Evid. 702, that is, a subject beyond the ken of the ordinary juror and reliably analyzed by modern science.
. We find appellant’s additional constitutional claims to be without merit. We do not think that the right to compulsory process includes a right to adduce otherwise excludable evidence.
