Expert Opinion Testimony is a type of testimony given by a witness who is qualified as an expert in a certain field. This type of testimony is usually presented in a court of law and can include scientific, medical, or technical opinions. It is often used in cases where the expert's opinion is needed to explain complex concepts and terminology. There are two main types of Expert Opinion Testimony: direct and circumstantial. Direct testimony is when an expert witness directly presents their opinion regarding a case. Circumstantial testimony is when the expert bases their opinion on the facts and evidence of the case. In both cases, the expert must be knowledgeable and experienced in their field. They must also be able to provide clear and concise explanations of their opinions. The court will then determine whether the testimony is reliable and admissible.