Rule 2:704.OPINION ON ULTIMATE ISSUE (Rule 2:704(a) derived from Code § 8.01- 401.3(B) and (C)).

Rule 2:704 draws opposite defaults for civil and criminal cases on a specific kind of opinion: one that speaks to the ultimate issue the fact-finder must decide. Subdivision (a) removes the old bar in civil cases — no expert or lay witness may be prohibited from expressing an otherwise admissible opinion or conclusion on any matter of fact just because that fact happens to be the ultimate issue, or critical to resolving the case. The rule preserves one hard line even in civil cases: a witness may never express an opinion that constitutes a conclusion of law. And it leaves undisturbed any other exceptions to the ultimate-fact-in-issue rule already recognized in Virginia, so this subdivision does not wipe out narrower, pre-existing limits that survive alongside it.

Subdivision (b) runs the opposite direction for criminal cases: opinion testimony on the ultimate issues of fact is not admissible. That default bar means an expert or lay witness in a criminal trial generally cannot tell the jury, in opinion form, how to resolve the question — such as guilt — that the jury must decide.

The criminal-case bar carries its own exception. It does not require excluding otherwise proper expert testimony about a witness’s or the defendant’s mental disorder and the hypothetical effect that disorder would have on a person in the witness’s or defendant’s situation — testimony relevant, for example, to issues like insanity or diminished capacity, framed hypothetically rather than as a direct opinion on guilt or innocence.