BEGUN IN 1973, THIS STUDY HAS AS ITS DATA BASE A PROBABILITY SAMPLE OF 1,888 FELONY ARRESTS WHOSE ITINERARY THROUGH THE SYSTEM WAS TRACED TO FINAL DISPOSITION. FOR A SUBSAMPLE OF 369 CASES, INTERVIEWS WERE CONDUCTED WITH THE ARRESTING POLICE OFFICER, THE ASSISTANT DISTRICT ATTORNEY, THE DEFENSE COUNSEL, AND THE JUDGE ABOUT THE RESPECTIVE PART EACH PLAYED IN THE PROCESS THAT CULMINATED IN DISPOSITION. ALTHOUGH THE LAW INSISTS ON THE PRESUMPTION OF INNOCENCE AND ONLY ABOUT 25 PERCENT OF ALL FELONY ARRESTS END IN A CUSTODY SENTENCE, THE LAW ENFORCEMENT PROCESS BEGINS WITH THE SUSPECTED DEFENDANT BEING TAKEN INTO CUSTODY. DENIAL OF BAIL IS RARE, ALTHOUGH NEW YORK LAW ALLOWS DENIAL FOR DEFENDANTS CHARGED WITH FELONIES. SUCH FACTORS AS CHARACTER, EMPLOYMENT HISTORY, AND PREVIOUS CRIMINAL RECORD ARE CONSIDERED BY THE JUDGE. WHEN BAIL IS SET, IT IS ABOVE $1,000 IN 40 PERCENT OF ALL CASES. STUDY DATA SHOW THAT ALMOST 50 PERCENT OF ALL DEFENDANTS CANNOT MAKE BAIL AS SET. PROHIBITIVELY HIGH BAIL CONTINUES TO BE IMPOSED DESPITE ITS NEGLIGIBLE IMPACT ON THE BAIL JUMPING RATE. THE BAIL SYSTEM DISCRIMINATES AGAINST THE INDIGENT DEFENDANT WHO CANNOT MAKE BAIL. IT KEEPS IN A JAIL DEFENDANTS WHO WOULD HAVE RETURNED TO COURT IF THEY HAD BEEN RELEASED, AND CONVICTED. IT RELEASES DEFENDANTS WHO SHOULD NOT BE RELEASED SIMPLY BECAUSE THEY CAN RAISE BAIL. MOREOVER, THE EXISTENCE OF PRETRIAL DETENTION INCREASES THE LIKELIHOOD THAT DEFENDANTS WILL BE CONVICTED AND, IF CONVICTED, WILL RECEIVE A CUSTODY SENTENCE. IN CONTRAST, EUROPEAN COUNTRIES ONLY ALLOW PRETRIAL DETENTION IF THE COURT BELIEVES THAT ONE OF THREE DANGERS IS LIKELY: FLIGHT, CONTINUATION OF CRIMINAL ACTIVITY, OR POSSIBILITY OF COLLUSION AND TAMPERING WITH THE EVIDENCE. IN VIEW OF ITS IMPERFECTIONS, THE AMERICAN SYSTEM SHOULD BE REEXAMINED. FOOTNOTES AND GRAPHS ARE INCLUDED. (LWM)