How have courts treated statements of alleged accomplices and coconspirators under oath in a criminal case?

under oath in a court proceeding and all out-of-court statements of accomplices and coconspirators used as substantive evidence of guilt which are made under suspect circumstances. The most obvious suspect circumstances occur when the accomplice has been arrested or is questioned by the police. These circumstances are most likely to induce self-serving motives and hence untrustworthy and unreliable evidence." (People v. Jeffery (1995) 37 Cal.App.4th 209, 218.)