Note : The NIBRS data set contains a wealth of information about crime: information about the offenses, victims, offenders, persons arrested, property loss. Due to the variety of data collected, it is much more difficult to analyze and interpret than the older summary UCR system data.

For this reason, few published reports have come out of federal, state, or academic establishments based on the NIBRS data set. What we are presenting here are the first steps in publishing NIBRS data as collected and processed by the Crime Reporting Unit of the Massachusetts State Police. These reports should be viewed carefully and cautiously. Although we will make every effort to put out reports that are clear and unambigous, the user should contact us if there are any questions about interpretation of the data contained herein.

In the above reports, all data received and processed by us which occurred in the specified year will be reported. There were approximately 134 police agencies reporting NIBRS data during this time period. Not all departments reported complete (12 months) data during this time, although the majority of them did.

Care must be used in examining these reports. One very important issue to consider when looking at the data is the "unit of count." For example, one measure of the unit of count is the number of incidents reporting during a month. Another measure of the same data is the number of victims within those incidents. Yet a third measure of the crime data is the number of offenses within those incidents. In each case, the total numbers may be different.

As a specific example, department "A" reported one incident in January, 2003. In that incident there were two victims: a male and a female. Both victims were robbed; the female was kidnapped and raped. In this example, there was one incident, two victims, and three offenses.