IL HB3719

Establishes new standards for expert testimony in Illinois civil cases, requiring expert opinions to be based on sufficient facts or data, reliable principles and methods, and reliable application to the case facts.

Limits lay witness opinions to those rationally based on perception, helpful to understanding testimony, and not involving scientific or specialized knowledge.

Requires mandatory pre-trial hearings and written disclosures for expert witnesses, including their qualifications, opinions, data, publications from the preceding 10 years, compensation, and prior testimony within 4 years.

Prohibits expert testimony based on contingent compensation tied to case outcomes and limits expert testimony to fields in which the witness is qualified.

Applies to all new civil actions and pending actions where trial has not been scheduled or is scheduled more than 90 days after the law's effective date; references federal Daubert standards for interpretation.