Assembly Bill 458 seeks to amend the existing statute regarding the admissibility of expert witness testimony in Wisconsin, aligning it with recent updates to the Federal Rule of Evidence (FRE) 702. The bill stipulates that an expert witness may testify if their scientific, technical, or specialized knowledge assists the trier of fact in understanding evidence or determining a fact at issue. A key change introduced by the bill is the requirement for the proponent of the testimony to demonstrate to the court that it is more likely than not that the testimony is based on sufficient facts or data, is the product of reliable principles and methods, and that the witness's opinion reflects a reliable application of those principles and methods to the case's facts.

The bill modifies the language of the current law by inserting specific requirements for the proponent of expert testimony, emphasizing the need for a demonstration of reliability and relevance. It also removes the phrase "witness has applied" to streamline the language regarding the application of principles and methods. This legislative change is intended to enhance the court's gatekeeping role in evaluating expert testimony, ensuring that only reliable and relevant expert opinions are presented in legal proceedings. The act will first apply to actions or special proceedings commenced on its effective date.

Statutes affected:
Bill Text: 907.02(1), 907.02