What is Legal Terms - Opinion Testimony?

Opinion Testimony information: Evidence that is based not on direct contact with an event, but based on belief. There are many situations where opinion testimony may come into evidence, but on ultimate issues, opinions will not suffice. Expert witnesses are different in that they base all of their testimony on opinion. Most courts will allow such expert evidence so long as a foundation is laid that the expert is qualified by education, training, or experience, and that the subject matter of the expert opinion is reliable, and that the expert opinion testimony will be helpful to the jury in understanding the factual issues to be decided.