Art. 704 Opinion on ultimate issue

Witnesses, including experts, can give opinions even if those opinions touch on the exact question the judge or jury needs to decide. In the past, some courts blocked this kind of testimony because it seemed to step on the jury's job. This rule says that is no longer a valid reason to keep the testimony out. If the opinion is otherwise allowed under the evidence rules, it can come in even though it relates to the main issue in the case.

There is one important limit in criminal cases. An expert witness cannot tell the jury whether they think the defendant is guilty or innocent. That decision belongs to the jury alone. Experts can explain evidence, give their professional opinion on technical matters, or interpret facts, but they cannot cross the line into telling the jury how to rule on guilt.