How the Study Was Conducted

For its study of homicide in Orange County from 1981 through 1995, the Times Orange County Edition relied largely on the Supplemental Homicide Reports that police agencies nationwide create for the FBI, which has gathered and analyzed data about crime in the United States since 1930.

To ensure that these computerized reports were complete, the homicide files were cross-checked against figures maintained by the Orange County sheriff-coroner’s office and used by the district attorney’s office.

The number of homicides in Orange County for the 15-year period, according to both sets of data, totaled 2,125--including justifiable homicides by both police officers and ordinary citizens, which were not included in any of The Times’ calculations.

These reports give the full name, age, race and sex of all homicide victims, as well as the date and time of their deaths, the jurisdiction (city, generally) where the homicide took place, and information about the circumstances of their deaths. The files also provide information about the weapon used, the wound area and the relationship--if known--between each homicide victim and his or her assailant.

Separate but related files give the age, race and sex of the killer or killers and date of any arrests, but do not give their identity.

The Times also used both computerized and printed Jurisdictional Trend Data for Orange County Agencies supplied by the state Department of Justice. This was used primarily to cross-check the number of homicides, homicide arrests and claimed homicide clearances in each jurisdiction.

For the dispositions of all homicide cases filed by county prosecutors for the years 1990 through 1995, The Times relied on annual reports prepared by the Orange County district attorney’s office and released to The Times in response to a request made under the provisions of the California Public Records Act.