THE MONTANA CRIMINAL JUSTICE DATA CENTER DEVELOPS, IMPLEMENTS, AND MAINTAINS DATA COLLECTION SYSTEMS TO PROVIDE BOTH ESSENTIAL INFORMATION ON CRIME AS IT OCCURS WITHIN THE STATE AND ON OFFENDERS WHO ARE APPREHENDED AND ENTER THE CRIMINAL JUSTICE SYSTEM, AND A STATISTICAL ANALYSIS OF CRIMINAL JUSTICE DATA. CRIMINAL JUSTICE DATA ARE FURNISHED TO THE DATA CENTER BY COUNTY LAW ENFORCEMENT AGENCIES, CITY POLICE DEPARTMENTS, AND GOVERNMENT AGENCIES. THE AMOUNT AND TYPE OF CRIME ARE BASED ON OFFENSES REPORTED TO THE POLICE AND DO NOT MEASURE THOSE OFFENSES THAT ARE NOT REPORTED OR OF WHICH THE POLICE ARE UNAWARE. OTHER FACTORS WHICH MAY INFLUENCE THE TYPE AND VOLUME OF CRIME ARE DENSITY AND SIZE OF COMMUNITY; AGE, RACE, AND SEX OF POPULATION; POPULATION ECONOMIC STATUS; STABILITY OF POPULATION; POPULATION EDUCATIONAL, RECREATIONAL, AND RELIGIOUS CHARACTERISTICS; EFFECTIVE STRENGTH OF POLICE FORCE; POLICIES OF PROSECUTING OFFICIALS AND COURTS; AND PUBLIC ATTITUDE TOWARD LAW AND ITS ENFORCEMENT. STATISTICAL MEASURES OF REPORTING CRIME DATA INCLUDE THE CRIME INDEX, CRIME RATE, AND CRIME SERIOUSNESS. THE CRIME RATE FOR MONTANA IN 1978 WAS 3,980. FOR THE THIRD TIME IN 3 YEARS, THE NUMBER OF INDEX CRIMES DECREASED. DATA SHOW THAT CRIMES AGAINST PROPERTY ACCOUNTED FOR 93.7 PERCENT OF ALL REPORTED OFFENSES, WHILE CRIMES AGAINST PERSONS ACCOUNTED FOR 5.9 PERCENT OF ALL REPORTED OFFENSES. FROM 1970 THROUGH 1978, THE NUMBER OF CRIMES INCREASED 55.8 PERCENT WHILE THE ESTIMATED POPULATION INCREASED ONLY 13.1 PERCENT. OF THE 31,246 MAJOR OFFENSES KNOWN, ONLY 1 OF EVERY 4 WAS CLEARED, EITHER BY ARREST OR EXCEPTIONAL MEANS. ALSO SHOWN ARE MONTANA INDEX CRIMES BY CONTRIBUTOR (LAW ENFORCEMENT AGENCY). DATA ARE PRESENTED FOR A CRIME OFFENSE PROFILE, CRIME CLOCKS, CLEARANCES, CRIME BY COUNTY, CRIME SERIOUSNESS, AND FOR ARRESTS (FELONY ARRESTS, MISDEMEANORS, AND ARRESTS BY SEX AND RACE OF OFFENDER). NUMEROUS TABLES AND GRAPHS ARE INCLUDED. (PRG)