Fourth Circuit Holds that Experts Must Separate Opinions From Fact Testimony and Lay Adequate Foundation for Both

Increasingly, in a number of contexts, experts are playing the role traditionally filled by attorneys: reviewing and explaining the relevance of the evidence, integrating it into the party's narrative, and mixing in opinions along the way. This has the potentially dangerous effect of placing the authority of an expert behind what is effectively a protracted version of a closing argument.

Recently, the US Court of Appeals for the Fourth Circuit created significant obstacles to at least some aspects of this type of expert testimony in United States v. Garcia, 2014 WL 1924857 (4th Cir. May 15, 2014). Garcia involved a prosecution for narcotics possession with intent to distribute. Central to the Government's case was an FBI Special Agent who testified both as a fact witness, based on her participation in the investigation, and as an expert witness, based on years of experience deciphering drug-trade slang. The agent's testimony consisted, in large part, of deciphering