Experts play a very important role in the litigation process. Personal injury attorneys in Illinois use several types of experts including but not limited to doctors, economists, safety and design experts.
Expert evidence must be presented within the tenets of evidence law. Generally, expert testimony is proper if it will assist the jury in understanding the evidence or to determine a fact in issue.
An expert must be qualified to give an opinion. Specifically, an expert must be qualified by virtue of knowledge, skill, experience, training or education.
The facts and data used by an expert in a particular case can be those perceived by or made known to the expert at or before trial. Additionally, if the facts or data relied on by the expert are reasonably used by experts in their field, the facts or data need not be admissible in evidence. Experts can testify to ultimate issues. Experts can testify as to conclusions. Experts can testify to hypothetical questions. And experts can testify to their opinions. It is often productive to think of experts as teachers, someone who can explain complex or specialized information to a jury.
In Illinois, Supreme Court Rule 213 controls expert witness disclosures.