Records, reports, statements, or data compilations, in any form, of public offices or agencies, setting forth…matters observed pursuant to duty imposed by law as to which matters there was a duty to report, excluding, however, in criminal cases matters observed by police officers and other law enforcement personnel.
In other words, police reports are not admissible in criminal cases. But why? That was the question addressed by Judge Posner in his recent opinion in United States v. Hatfield, 2010 WL 114930 (7th Cir. 2010), although his analysis was irrelevant to his conclusion.
That left the Seventh Circuit with the question of why police reports are inadmissible in criminal cases. The court noted that