ASSUMPTIONS MADE BY THE LEGAL SYSTEM ABOUT THE JURY SYSTEM INVOLVE THE COMPOSITION OF THE VENIRE, THE EFFECTIVENESS OF THE VOIR DIRE PROCESS, THE ABILITY OF JURORS TO DISREGARD PRETRIAL PUBLICITY AND INADMISSIBLE EVIDENCE, THE CAPACITIES OF JURORS TO RECONSTRUCT THE TRIAL PRESENTATION FROM MEMORY, AND THE ABILITY OF THE JURY AS A DELIBERATIVE BODY TO ACT IN A RATIONAL, EVIDENCE-ORIENTED MANNER. REGARDING THE COMPOSITION OF THE VENIRE, A RECENT STUDY (ALKER, HOSTICKA, AND MITCHELL, 1976) STILL FOUND SOURCES OF BIAS IN THE USE OF OUTDATED VOTER REGISTRATION LISTS, UNRETURNED QUESTIONNAIRES, AND THE APPLICATION OF EXEMPTION PROCEDURES. THE VOIR DIRE, INTENDED TO ELIMINATE POTENTIAL JURORS WHO ARE BIASED ALSO HAS YET TO BE PROVEN EFFICIENT IN THIS PROCESS. ACCORDING TO EMPIRICAL EVIDENCE, MANY TRIAL ATTORNEYS USE VOIR DIRE TO LOAD A JURY WITH PERSONS LIKELY TO BE SUPPORTIVE OF THEIR INTERESTS IN THE CASE. IN ADDITION JURORS NOT ONLY CANNOT DISREGARD INADMISSIBLE EVIDENCE, BUT ADMONITIONS BY THE JUDGE TO DISREGARD SUCH EVIDENCE STIMULATE JURORS TO ATTACH IMPORTANCE TO IT. DATA SHOW THAT JURORS TEND TO BE CONFUSED ABOUT THE MEANING OF REASONABLE DOUBT, POINTING TO THE NEED FOR FURTHER RESEARCH BEFORE THE TENDENCY OF JUDGES TO LET THE JURY DEFINE REASONABLE DOUBT CAN BE SUPPORTED. DATA ON HUMAN RETENTION CAPABILITIES ALSO QUESTIONS THE ASSUMPTION THAT JURORS CAN REMEMBER ALL THE FACTS PRESENTED IN THE COURSE OF A TRIAL WITHOUT TAKING NOTES. FINALLY, THE ASSUMPTION THAT JURY DELIBERATIONS ARE OBJECTIVE AND FREE OF PRESSURES TO UNIFORMITY THAT WOULD LEAD INDIVIDUAL JURORS TO SUPPORT A PUBLIC OUTCOME THAT IS CONTRARY TO THEIR PRIVATE BELIEFS IS NOT SUPPORTED BY SHOWING THAT INDIVIDUAL JURORS ARE SUBJECTED TO PRESSURES TO CONFORM TO DOMINANT OPINIONS, BOTH IN THE TRIAL AND IN JURY DELIBERATIONS. SUGGESTED JURY REFORMS IN THE LIGHT OF THIS EVIDENCE ARE OFFERED. REFERENCES ARE PROVIDED. (RCB)