A subtle and frequent problem recently arose in a jury trial that I was involved in. All too often police officers will relate information that they have gathered from non testifying sources (i.e. confidential informants). The ostensible purpose for this testimony is to explain to the jury, the "background" of the investigation or "why they were there (e.g. conducting surveillance)." Typically, the information comes from a nontestifying confidential informant who is seeking some type of consideration. It is also typical that the content of the information is of the nature of "bad character" evidence. Way way too often either an objection is not made or the trial court allows this testimony because the state contends it is not for the truth of the matter asserted but is relevant for the reasons previously noted; background or course of the investigation. Unfortunately, the problem is then compounded because not only does the police officer who spoke with the informant testify but also all the subsequent radio calls among the responding officers come into evidence.
It is incumbent on defense counsel to object to this type of testimony. The grounds for the objection should be apparent. First, it is hearsay and a violation of the right to confrontation per Crawford. Second, it is not relevant and even if it is, the undue prejudice substantially outweighs its probative value (remember that probative value should be looked at on an incremental basis). Third, it is inadmissible character evidence.
Wisconsin practitioners should have two cases at their fingertips. First, there is an unpublished decision that agreed with the above analysis with little or no detailed discussion of the issues. In State v. ODonnell, 2000 WI App 1, the state conceded it was error but harmless. The appellate court disagreed and ordered a new trial.
A much more thorough discussion takes place in the 7th circuit case of United States v. Silva, 380 F.3d. 1018 (2004). An excerpt from the case relates a portion of the argument:
The prosecutor contends that most of the statements were admissible to show “the actions taken by [each] witness”. Allowing agents to narrate the course of their investigations, and thus spread before juries damning information that is not subject to cross-examination, would go far toward abrogating the defendant's rights under the sixth amendment and the hearsay rule. This court has warned against the potential for abuse when police testify to the out-of-court statements of a confidential informant. See United States v. Lovelace, 123 F.3d 650 (7th Cir.1997). See also McCormick on Evidence § 249 (5th ed. 1999).
While Silva acknowledges that sometimes this information could be relevant, the 403 balancing test will frequently tip in the defendants favor. Go forth and fight.