Articles

When it comes to impeachment—attacking the credibility of a witness—lawyers sometimes fail to consider whether the evidence is substantive or pure impeachment. It can lead to an exchange like the following:

Judge: Are you offering this evidence as pure impeachment or to establish its truth?

Lawyer: Yes.

Knowing whether impeachment evidence may also be substantive is important. Substantive evidence “is offered to establish the truth of a matter to be determined by...

"Like a house built on sand, the expert's opinion is no better than the facts upon which it is based." This famous line from Kennemur v. State of California, 133 Cal. App. 3d 907, 924 (1982), can be found in virtually every California motion to exclude an opponent's expert witness. And it is typically cited for one of two arguments:

There is the junk science argument. This argument seeks to show the expert's reasoning or methodology is unreliable. It is used against the expert...

In People v. Sanchez, 63 Cal. 4th 665 (2016), the California Supreme Court decided that an expert witness cannot relay hearsay that communicates case-specific facts to the jury. This post examines how trial lawyers can and should examine expert witnesses in the post-Sanchez era. 

As a starting point, practitioners should master familiarity with Evidence Code section 801. Section 801 sets forth the allowable limits on which expert witnesses may offer opinions as well as the...