Rule 704 Opinion on Ultimate Issue

A witness who qualifies as an expert can give their opinion on the main question the judge or jury needs to decide. Just because their opinion touches on that big central question does not make it off-limits in court.

For example, a medical expert can say "in my opinion, the defendant was not able to understand what they were doing," even though that is exactly what the jury needs to figure out. The opinion is still allowed in.

The judge or jury does not have to agree with the expert. They can still weigh the opinion against other evidence and make their own decision. The rule just means the opinion cannot be thrown out simply because it addresses the heart of the case.