At least three federal circuits have approved a trial judge's decision to give a cautionary accomplice testimony instruction when an alleged accomplice testifies for the defendant. Several state courts and at least one military court have done likewise. Other state courts, in contrast, have explicitly disapproved giving such an instruction and courts in at least one state are divided on the issue.
Part I of this article briefly reviews how courts have traditionally determined whether a prosecution witness is an "accomplice,” and will provide representative samples of cautionary instructions. Part II will examine the federal decisions8 upholding giving a similar instruction when the prosecutor claims that a defense witness is an accomplice and will show that several United States Supreme Court decisions which are frequently cited as supporting the practice do not really do so. Part III will argue that, except perhaps in very rare cases, it is not appropriate to give such an instruction about a defense witness.
Clifford S. Fishman, Defense Witness as ‘Accomplice’: Should the Trial Judge Give a ‘Care and Caution’ Instruction?, 96 J. CRIM. L. & CRIMINOLOGY 1 (2005).