THE PRISONER'S DILEMMA HAS BECOME THE CLASSIC EXAMPLE OF A SITUATION IN WHICH THE PROCESS OF COOPERATION ITSELF PRODUCES INCENTIVES TO NOT COOPERATE. AN IMPLICATION OF THE DILEMMA IS THAT THE PROSECUTOR CAN OBTAIN LEVERAGE IN CASES INVOLVING CODEFENDANTS NOT AVAILABLE IN OTHER CASES, BY EXCHANGING A PROSPECT OF REDUCTION IN SENTENCE BY WAY OF PLEA BARGAINING IN RETURN FOR INFORMATION OR TESTIMONY AGAINST OTHER CODEFENDANTS. THE PRISONER'S DILEMMA IS DESCRIBED, PREVIOUS ANALYSES OF THE DILEMMA ARE REVIEWED, AND THEN THE IMPLICATION STATED ABOVE IS TESED AGAINST AVAILABLE DATA. FOR A COHORT OF DEFENDANTS IN ROBBERY CASES, IT IS FOUND THAT NEITHER THE PLEA RATE, CONVICTION RATE, NOR INCARCERATION RATE IS SIGNIFICANTLY HIGHER IN CASES INVOLVING CODEFENDANTS THAN IN OTHER CASES. (AUTHOR ABSTRACT)....BDC