A recent Ninth Circuit case highlights the importance of disclosing impeachment evidence and the consequences of failing to do so. The prosecutor requested a criminal history check on a key government witness. The prosecutor indicated he was unaware of the criminal history which was not disclosed to the defense. The defendant was convicted and subsequently the criminal history evidence came to light.
The prosecution’s failure to disclose to the defendant the criminal history of a key witness violated the defendant’s due process rights under Brady v. Maryland, 373 U.S. 83 (1963); the criminal convictions were admissible under FRE 609 and the prior acts of theft or dishonesty were admissible under FRE 608(b), in United States v. Price, __ F.3d __ (9th Cir. May 21, 2009) (Nos. 05-30323, 06-30157).
Getting this type of discovery is a frequent problem in military cases. You will notice that Price does not cite to Henthorn. It is unlikely you will find a reference in military cases to Henthorn as a legal standard in the military for background checks on prosecution witnesses. Military discovery is broader than in the civilian community, and you should take the position that Henthorn is more restrictive than contemplated in military practice. An additional argument is that such background checks do not require a discovery request; the duty on the prosecutor is a self-executing one that must be personally done in all cases.
"the individual prosecutor has a duty to learn of any favorable evidence known to the others acting on the government’s behalf in the case, including the police."
Kyles v. Whitley, 514 U.S. 419 (1995).