Prosecutors love using summary witnesses, usually their case agents, at trial. As the closing, wrap-up witness, an agent can testify about summary charts which he/she prepared, nicely aligning the counts and charges with key documentary exhibits or with trial testimony, or can put into evidence the inculpatory statements made by the defendant. Put on the stand as an opening witness, an agent can trace the course of his or her investigation, describe the execution of a search, or carefully establishing the reasons that the government focused its attention on the individual now sitting at the defense table. In cases involving complex organizations, such as gang or organized crime prosecutions, an agent may judiciously describe enterprise structures and, based on the agent’s investigative experience, the roles typically played by certain sorts of individuals in those entities.

But when the agent-witness testifies first, and goes further to anticipate and summarize evidence which has not yet been admitted, then the government is on very thin ice, as the First Circuit recently emphasized in United States v. Rodriguez-Adorno, 695 F.3d 32 (1st Cir. 2012). This was a carjacking case, and the case agent from the FBI led off the government’s presentation. Unfortunately, the agent went beyond a description of his investigative efforts -- he identified the defendant as the individual depicted on surveillance tapes of the deadly episode and also testified that seven or eight witnesses would testify that the defendant was involved in the crime.

The court of appeals reiterated its concerns with overview testimony from the government early in a trial, warning that such witnesses must take care not to describe the theory of prosecution based on hearsay statements made to the agent and must not implicate the defendant in the charged offense. In this case for example, the agent repeatedly referred to the episode as a “carjacking” and a “murder” of the driver, statements which assumed the offense had been proven, and which were admitted in error. It was also error (i) to admit the agent’s testimony about the witnesses who would implicate the defendant, which was hearsay, and (ii) to have allowed the agent to identify the defendant on the video, which was an impermissible lay opinion under FRE 701, since the jury was as well-suited to identify the individual on the video, rendering the agent’s opinion unhelpful to the trier of fact.

In the end, the First Circuit deemed the errors harmless, of course, and affirmed the conviction, but the lessons are clear and the path to a well-taken objection or in limine motion illuminated.