Testimony in the form of an opinion or inference otherwise admissible is not objectionable because it includes an ultimate issue to be decided by the trier of fact.
This statute gets rid of the old common law rule that prohibited witnesses from giving an opinion on the "ultimate issue" of the case. The modern view is that as long as an opinion is otherwise admissible (meaning it's helpful and based on a proper foundation), it can be about an ultimate issue. For example, an accident reconstruction expert can testify that, in their opinion, a driver's speed was "unsafe," even though whether the driver was negligent is an ultimate issue for the jury to decide. The jury is still free to accept or reject the expert's opinion.
