US v. Diaz, 9th Cir., filed 12/6/17: The Limits (or Not!) of Expert Witness Testimony in White Collar Criminal Case

I find this opinion disturbing because I think too often government expert witnesses are allowed too free rein in their testimonies in the first place, to the obvious disadvantage of criminal defendants, and this decision clearly will not be slowing down that train anytime soon.  Here, the Court did not find error when the government’s expert witness couched its opinion in language that tracked the criminal statute. 

Dr. Diaz was convicted of essentially operating a pill mill. He was indicted for 88 counts of distributing controlled prescription drugs in violation of 21 U.S.C. §841 (a)(1).  He was tried on 79 of these counts. To be found guilty of this offense, the government had to prove:

            (1) that the practitioner distributed controlled substances, (2) that the distribution of those controlled substances was outside the usual course of professional practice and without a legitimate medical purpose, and (3) that the practitioner acted with intent to distribute the drugs and with intent to distribute the outside the course of professional practice.

The government offered the testimony of Dr. Rick Chavez, who testified, without objection, that Diaz’s scripts were written “outside the usual course of medical practice” and “without a legitimate purpose.” On appeal, Diaz complained that this testimony impermissibly offered opinion testimony as to a legal conclusion (note that this testimony tracked the elements of the statute).

Importantly, the Court reviewed this issue applying its plain error standard since trial counsel did not object to the evidence during trial.  The Court doesn’t suggest it would have ruled otherwise had the issue been properly preserved, but for purposes of distinguishing in another case, this may be a nominally relevant distinction.

Federal Rule of Evidence 702(a) requires that expert testimony “help the trier of fact to understand the evidence or to determine a fact in issue.” FRE 704(a) clarifies that “[a]n opinion is not objectionable just because it embraces an ultimate issue.”

The Court here reasons that, although the value of expert testimony lies in the specialized knowledge that an expert brings to bear on an issue in dispute, it is sometimes impossible for an expert to render his or her opinion without resorting to language that is used in the applicable legal standard:

We hold that if the terms used by an expert witness do not have a specialized meaning in law and do not represent an attempt to instruct the jury on the law, or how to apply the law to the facts of the case, the testimony is not an impermissible legal conclusion.

In other words, just because an expert uses language that appears to offer a legal conclusion, it’s okay so long as he needed to use that language to convey his expert opinion, and the language does not have a “separate, distinct, and specialized” legal significance.  I can see this holding opening up some additional pre-trial litigation, as trial counsel will likely seek a hearing on just how an expert intends to phrase his opinions so as not appear to be embracing a legal conclusion.

But then the Court said this, suggesting that Diaz should have presented his own expert.  I’m not sure the relevance of this, other than to put the burden on him to have presented a defense which, of course, he was under no constitutional obligation to do:

In the context of this case, Dr. Chavez’s testimony was no doubt persuasive to the jury, but that is because it was uncontradicted and consistent with a great deal of other uncontradicted evidence. Diaz did not proffer a competing expert opinion. Had he presented such testimony, it would have been for the jury to weigh the experts’ competing opinions concerning the medically acceptable standard for prescribing controlled substances to the people who sought them from Diaz.

This is a case that the government will surely enjoy.