Colorado Supreme Court Defines Boundary for Expert Testimony

Venalonzo test lays out ‘ordinary person’ standard for admissible lay opinion.

Last week, the state’s high court weighed in on an all-too-common point of contention between criminal prosecutors and defense attorneys: When does lay witness testimony cross over into expert testimony?

The Colorado Supreme Court published a pair of opinions Feb. 6 that refined the line between admissible opinions by lay witnesses as opposed to expert opinions. In Venalonzo v. People, the court laid out a test by which a lay witness’ opinion is admissible as long as the testimony could be based on “an ordinary person’s” experience and knowledge. The test, which the court also applied to People v. Ramos, could allow courts to better weed out expert testimony taking the form of lay opinion.

The new test could have attorneys in criminal cases paying extra attention to how they present their witnesses as well as their line of questioning.

Colorado Rule of Evidence 702 defines an expert witness to be “qualified … by knowledge, skill, experience, training, or education, may testify thereto in the form of an opinion or otherwise.” According to Rule 701, a lay witness’ opinions are limited to those that aren’t “based on scientific, technical or other specialized knowledge within the scope of (Rule) 702.”

To read this story and other complete articles featured in the February 13, 2017 print edition of Law Week Colorado, copies are available for purchase online.