ONCE A WIDESPREAD PRACTICE, PRISON MEDICAL RESEARCH NOW REMAINS ONLY IN THREE PRISON PROGRAMS. HERE INMATES ARE USED TO TEST NEW AND REFORMULATED DRUGS UNDER STRICT CONTROL OF THE FOOD AND DRUG ADMINISTRATION (FDA), AS WELL AS CAUTIOUS DRUG COMPANY EXECUTIVES AND DOCTORS. A FEW YEARS AGO 85 PERCENT OF ALL DRUG TESTING WAS DONE IN PRISONS; NOW IT IS DOWN TO 15 PERCENT. ARGUMENTS THAT CAUSED THIS CHANGE CONTEND THAT PRISON ENVIRONMENTS ARE COERCIVE AND THAT INMATE HEALTH AND FREE CHOICE IS EXPLOITED FOR DRUG COMPANY PROFITS. ON THE OTHER HAND, PRISON RESEARCH SUPPORTERS ARGUE DRUG STUDIES REQUIRE CAREFULLY CONTROLLED GROUPS THAT CAN BE MONITORED AS RESEARCH PROGRESSES, AND THAT PRISONERS ARE IDEAL SUBJECTS FOR RELIABLE TESTS. THE MOST ENTHUSIASTIC SUPPORTERS OF THE PROGRAMS ARE THEIR SUPPOSED VICTIMS--THE INMATES, WHO CAN MAKE MANY TIMES THE RATE OF PAY THEY GET FOR PRISON LABOR AND WHO ARE HAPPY TO ESCAPE FROM THE DANGEROUS AND UNCERTAIN LIFE IN PRISON YARDS. IN THE PAST, PARTICIPATION IN DRUG TESTING WAS REWARDED WITH SHORTER PRISON STAYS, BUT THIS PRACTICE HAS BEEN BANNED. IN SOME PROJECTS THE DRUGS THEMSELVES PROVIDED ADDED INCENTIVE FOR ADDICTED PRISONERS. DESPITE THE POST NUREMBERG INTERNATIONAL CODE OF ETHICS REGULATING EXPERIMENTS ON PRISONERS, MEDICAL RESEARCH IN PRISONS REACHED ITS APEX IN THE U.S. BETWEEN 1965 AND 1975. FDA REGULATIONS WERE FOLLOWED, AND MOST PRISONERS WERE UNHARMED. NEVERTHELESS, SOME POORLY RUN, MISPLANNED, AND DANGEROUS EXPERIMENTS WERE DISCOVERED BY THE PRESS. THIS RESULTED IN THE OVERALL PHASEOUT OF PRISON TESTING. ALTERNATIVE EXPERIMENTAL GROUPS MUST NOW BE SOUGHT OUT IN THE SOCIETY AT LARGE. ILLUSTRATIONS ARE INCLUDED. (MRK)