THE INTRODUCTION OF MANDATORY MINIMUM PRISON SENTENCES FOR THOSE CONVICTED OF USING OR CARRYING A GUN DURING THE COMMISSION OF A CRIME IS FREQUENTLY PROPOSED AS A METHOD FOR CURBING MISUSE OF WEAPONS. SUCH PROVISIONS HAVE ALREADY BEEN INCORPORATED INTO THE CRIMINAL LAWS OF MANY STATES, AND CURRENT OPINION AMONG PUBLIC OFFICIALS AT ALL LEVELS OF GOVERNMENT FAVORS INCREASED RELIANCE ON THIS CONCEPT. THIS REPORT, ISSUED BY THE UNITED STATES CONFERENCE OF MAYORS, EXPLORES THE LEGAL, PROCEDURAL, FISCAL, PRACTICAL, AND BEHAVIORAL QUESTIONS WHICH WILL DETERMINE WHETHER MANDATORY MINIMUM PRISON SENTENCES WILL DETER GUN CRIME. IT CONCLUDES THAT MANDATORY SENTENCES WILL NOT SIGNIFICANTLY REDUCE THE LEVEL OF SERIOUS CRIME, AND MAY IN FACT SEVERELY HAMPER THE CRIMINAL JUSTICE PROCESS. THE PROS AND CONS OF MANDATORY MINIMUM SENTENCES ARE ANALYZED IN ORDER TO DEVELOP A REALISTIC PICTURE OF WHAT THE IMPACT OF SENTENCING MIGHT BE ON GUN USING OFFENDERS. THE FOUR BASIC ASSUMPTIONS OF THE PROPONENTS OF MANDATORY SENTENCING ARE EXAMINED IN TURN. THESE ARE: 1) THAT THE VIOLENT OFFENDERS WHO ARE CONVICTED UNDER OUR LEGAL SYSTEM ARE RESPONSIBLE FOR THE BULK OF VIOLENT CRIME; 2) SINCE MOST OF THESE OFFENDERS ARE RECIDIVISTS, IMPRISONING THEM WILL SIGNIFICANTLY REDUCE THE QUANTITY OF CRIMINAL VIOLENCE IN SOCIETY; 3) THAT MANDATORY PRISON SENTENCES WILL ACT AS A DETERRENT; AND 4) THAT MANDATORY PRISON SENTENCES WILL HAVE LITTLE ADVERSE EFFECT ON THE CRIMINAL JUSTICE SYSTEM AS A WHOLE. IN EXAMINING THESE ASSUMPTIONS, THE REPORT EXPLORES THE MANNER IN WHICH THE CRIMINAL JUSTICE SYSTEM TYPICALLY RESPONDS TO STATUTORY REQUIREMENTS TO IMPOSE MANDATORY MINIMUM PRISON SENTENCES. CENTRAL TO THESE EXPLORATIONS ARE CONSIDERATION OF THE JUDICIAL SYSTEM'S NEED FOR EFFICIENCY, ITS GOAL OF FAIRNESS, THE ROLE OF PLEA BARGAINING, THE USE OF PROSECUTORIAL DISCRETION, THE DEFENDANT'S RIGHT TO A JURY TRIAL, AND THE AVAILABILITY OF PRISON FACILITIES. EVIDENCE WHICH REFUTES EACH OF THE ASSUMPTIONS ON MANDATORY SENTENCING IS PRESENTED. THE AUTHOR CONCLUDES THAT MANDATORY SENTENCES WOULD REDUCE JUDICIAL EFFICIENCY, AND CAUSE SEVERE STRAINS ON THE CORRECTIONS SYSTEM. HE NOTES THAT THE U.S. CONFERENCE OF MAYORS FAVORS A BAN ON THE MANUFACTURE, IMPORTATION, SALE, AND PRIVATE POSSESSION OF HANDGUNS, EXCEPT FOR USE BY LAW ENFORCEMENT PERSONNEL, MILITARY, AND SPORTSMEN CLUBS. FOR A SECOND VOLUME IN THIS SERIES, SEE NCJ-35035. (AUTHOR ABSTRACT MODIFIED) (SNI ABSTRACT)