Explaining a Policy Without Deciding Intent: Rule 704(b) in Nevin Shetty's Appeal

Expert testimony can bear on a person's state of mind without directly telling the jury what that person thought. Nevin Shetty's July 31, 2026 opening brief relies on that distinction when challenging restrictions on his corporate-law experts. The appeal argues that opinions about how finance officers could understand an investment policy were treated too broadly as prohibited opinions about Shetty's own intent.

The legal focus is Federal Rule of Evidence 704(b) and the Supreme Court's 2024 decision in Diaz v. United States. Those authorities distinguish an expert's direct conclusion about the defendant's required mental state from other testimony that may help jurors evaluate the issue. Shetty's lawyers ask the Ninth Circuit to apply that distinction to the policy evidence excluded in his trial.

Rule 704(b) bars an expert in a criminal case from giving an opinion about whether the defendant had the mental state or condition constituting an element of the charged crime or a defense. That restriction preserves the fact finder's responsibility for the defendant-specific conclusion.

The rule does not say that every expert opinion relevant to mental state must be excluded. Evidence often supplies context from which a jury draws an inference about knowledge or intent. The question is whether the expert crosses the line into the particular conclusion the rule reserves for the jury, rather than merely contributing information bearing on it.

The distinction matters to both sides. It prevents an expert's credentials from becoming a substitute for a verdict on intent, while allowing appropriate specialized assistance. Other admissibility requirements remain in place, including relevance and reliability. Avoiding a Rule 704(b) objection does not by itself establish that testimony must be admitted.

In the Supreme Court's Diaz case, a prosecution expert testified that most drug couriers know they are carrying drugs. The Court held that this was not an opinion about whether Diaz herself possessed the required knowledge. The testimony described a group without necessarily identifying the defendant as one of the group's knowing members.

That holding did not give experts unrestricted permission to disguise defendant-specific conclusions as general observations. It addressed the testimony presented in that case and the scope of Rule 704(b). Justice Jackson's concurrence also emphasized that the rule applies to defense experts as well as prosecution experts, within the broader evidentiary framework.

The holding supplies the legal distinction Shetty's lawyers invoke. Their application concerns corporate authority rather than drug transportation. The appeal argues that testimony about how finance officers could interpret a policy falls on the permissible side of the distinction, while a direct expert statement about what Shetty himself believed would remain prohibited.

The July 2024 response concerning expert testimony expressly distinguished these two forms of opinion. Counsel said the proposed corporate-law experts would not opine on Shetty's own interpretation or whether he intended a fraudulent scheme. They would instead explain how a corporate officer might reasonably understand the policy.

That proposed division of work leaves a substantial task to the jury. An expert might identify a plausible professional interpretation; the jury would still decide whether Shetty held that interpretation, whether the evidence supported his account, and how the finding related to the charged conduct. The expert's analysis would be a basis for assessment, not a declaration that the defense was true.

The opening brief says the district court nevertheless restricted policy opinions partly because they went to Shetty's mental state. Counsel argues that this description swept too broadly. The relevant question, in the defense's account, was not merely whether the testimony could affect the intent analysis, but whether the expert would give the forbidden defendant-specific conclusion.

Fabric's investment policy and board delegation were written materials that could be analyzed independently of Shetty's private thoughts. The experts' proposed discussion of officer discretion, investment-manager provisions, and corporate practice concerned that external framework. Counsel argues that such analysis could help evaluate whether the claimed understanding was plausible.

That does not turn a plausible interpretation into actual authorization. Nor does it prove an asserted belief was sincerely held. Keeping those questions separate is what makes the defense argument coherent: specialized analysis could inform the jury without replacing its assessment of Shetty's credibility and the other evidence.

The broader importance of a clearly defined fraud standard appears in the NACDL amicus brief from the district-court proceedings. Its position is separate from the Rule 704(b) question, but the shared concern is precision about what must be proved. Neither the amicus nor the appeal is itself a judicial ruling accepting Shetty's defense.

The July 31 brief followed a conviction on four wire-fraud counts on November 7, 2025, and a sentence of two years in prison on March 5, 2026. Counsel asks for a new trial based in part on the exclusion of policy testimony. The brief identifies Diaz as a reason to reconsider the district court's treatment of that evidence.

Shetty's public materials provide additional context for the case and its documents. This appellate argument is especially useful because it identifies a legal boundary instead of asking for an exception based on sympathy. It accepts that experts cannot decide Shetty's mental state while arguing that they should have been permitted to explain the professional setting in which the jury evaluated it.

The distinction is narrow but consequential. A fair assessment should ask what the expert actually proposed to say, what inference remained for the jury, and whether another evidentiary rule independently justified exclusion. Shetty's appeal argues that those questions were compressed into an overly broad mental-state objection, depriving the defense of useful, properly limited support.