Interpretations of the law, conclusions of law, expert opinions on the application of law to facts or use of a term that has both an everyday meaning as well as a legal one: What is an expert witness allowed to say when matters of law and matters of fact are intermingled?
The boundaries on what kind of expert testimony is admissible is in broad terms determined by a policy and a rule.
The policy is that trial judges have broad discretion in determining what expert opinion is admissible. Although the proponent of expert testimony bears the burden of establishing its admissibility by a preponderance of the evidence the rejection of expert testimony is the exception rather than the rule and the admission of expert testimony by the trial judge will not be disturbed on review unless found to be “manifestly erroneous.” United States v. Wexler, 522 F.3d 194, 204 (2d Cir. 2008).
The rule is Federal Rule of Evidence 702. That rule requires that to be admissible expert testimony must be by an expert that is qualified by some combination of relevant knowledge, skill, experience, training or education and the testimony must aid the trier of fact (judge or jury) to understand the context of the legal dispute and be based on the application of reliable methodology to the facts in evidence.
For expert testimony to be admissible the trial judge must make the threshold determination that the proposed witness’s scientific, technical, or other specialized knowledge will assist the trier of fact to understand the evidence or to determine a fact in issue.
Within these broad parameters the expert testimony becomes objectionable when it does one of three things, either it usurps the role of the judge in giving instructions to the jury on what the law requires to reach a certain verdict, or the testimony opines on the state of mind of a defendant where the state of mind of a defendant is an element of the crime charged (it is also generally objectionable in civil cases since the state of mind of a defendant would rarely be within the expertise of an expert, unless, perhaps, the expert was a psychiatrist or psychologist), or the expert makes a conclusion as to the legal consequences of the evidence in the case.
Application of these basic rules limiting expert testimony can be difficult since what is an issue of fact that is within the expertise of the witness and what is an impermissible conclusion of law can be very hard to differentiate.
An expert can provide relevant context, such as customary professional or industry practice in a specialized field, if it will be helpful to the jury. See Marx & Co., v. Diners Club, Inc. 550 F. 505 (2d Cir.1977), where the court stated that a witness who was qualified as an expert in securities regulation, and therefore was competent to explain to the jury the step-by-step practices ordinarily followed by lawyers and corporations in shepherding a registration statement through the SEC.
The rules for lawyers giving expert testimony are really the same as for non-lawyers. Lawyers who are experts on some area of law can explain legal requirements within their field of expertise, but cannot make legal conclusions (See Marx V. Diners Club).
In another frequently cited case making the same point: United States v. Mikutowicz, 365 F.3d 65 (1st Cir. 2004), an accountant was allowed to testify if certain deductions were appropriate under IRS regulations, holding that this did not amount to offering a legal conclusion, but instead drew on specialized knowledge of accounting and tax practices.
The court stated that: “It is well established in several circuits that “[e]xpert testimony by an IRS agent which expresses an opinion as to the proper tax consequences of a transaction is admissible evidence.”
The court went on to say: The primary limitation on this type of evidence is that the agent may not testify about the defendant’s state of mind when the challenged deductions were claimed. See Fed.R.Evid. 704(b) (expert may not testify to mental state of defendant where mental state is element of charged offense); Sabino, 274 F.3d at 1067 (“[I]n a tax case, the summary witness is allowed to summarize and analyze the facts indicating willful tax evasion so long as the witness does not directly embrace the ultimate question of whether the defendant did in fact intend to evade income taxes.”)”.
Rule 704(a) of the Federal Rules of Evidence provides that “[a]n opinion is not objectionable just because it embraces an ultimate issue of fact,”. The apparent rational for Rule 704 (a) is that, if an expert witness provides relevant and reliable testimony on an issue on which the fact finder needs help understanding, then the expert should be able to state the conclusion that the testimony leads to and not leave the logical conclusion of the testimony a blank for the trier of fact to struggle to fill in.
As the court in United States v. Scop, 846 F2d 135 (2d Cir 1988) stated: “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. They also stand ready to exclude opinions phrased in terms of inadequately explored legal criteria.
Thus the question, “Did T have capacity to make a will?” would be excluded, while the question, “Did T have sufficient mental capacity to know the nature and extent of his property and the natural objects of his bounty and to formulate a rational scheme of distribution?” would be allowed. McCormick § 12.”
In a similar vein another court suggested how a legal conclusion could be reframed in acceptable non-legal terms. “The precise language of the question put to Dr. Quiroga was whether “Torres had been discriminated against because of her national origin.” In concluding that this question called for an improper legal conclusion, we rely on several factors. First, the question tracks almost verbatim the language of the applicable statute. Title VII makes it unlawful for an employer to “discriminate against any individual . . . because of such individual’s . . . national origin.” See 42 U.S.C. § 2000e-2. Second, the term “discrimination” has a specialized meaning in the law and in lay use the term has a distinctly less precise meaning. See Ward v. Westland Plastics, Inc., 651 F.2d 1266, 1271 (9th Cir. 1980) (witness “incompetent to voice an opinion on whether that or any other conduct constituted illegal sex discrimination”).
We emphasize that a more carefully phrased question could have elicited similar information and avoided the problem of testimony containing a legal conclusion. The defendants could have asked Dr. Quiroga whether she believed Torres’ national origin “motivated” the hiring decision.
This type of question would directly address the factual issue of Dr. Malueg’s intent without implicating any legal terminology. Cf. Bohannon, 652 F.2d at 731-33. “So, it seems that to preserve the legal proprieties of the exclusive prerogative of the court to say what the law is an expert must carefully frame his or her conclusion as a factual one, although it embodies an implicit legal conclusion. The essential meaning of the conclusion can be the same, but to be admissible the outward formulation needs be factual.
In conclusion, when an expert witness states a factual conclusion that has in it an implicit legal conclusion it is a departure from the common law rule that only the judge is authorized to instruct the jury on what the law is. This liberality is bounded in three ways that have been already been noted.
First, the expert must be qualified and the expert’s opinion must be based on the evidence that has been presented in court. Second, the expert cannot make conclusions as to a defendant’s state of mind, where that state of mind is an element of a criminal charge. The third limitation is more subtle and is a matter of form over substance.
Even if an expert testimony necessarily implies a legal conclusion, the expert cannot state his conclusion as an outcome required by the law, which would be objectionable as a legal conclusion. Instead, the legal conclusion must be formulated as a matter of fact such as “the defendant should not have traded on that non-public information” or “the spouse should not have been required to co-sign on her husband’s business loans.”
Prepared by Geoff Minott – November 2024