Criminal records of homicide offenders

Homicide prevention strategies can be either targeted toward high-risk groups or addressed to the population at large. One high-risk group of particular interest is adults with a criminal record. But the prevalence of a criminal record among homicide offenders has not been reliably quantified, nor has the prevalence of criminal record in the general population.

To determine what portion of the homicide problem would be addressed by interventions linked to arrest or conviction.

A case-control analysis was performed using a comprehensive data set of all arrests and felony convictions in Illinois for 1990-2001. Cases were defined as Illinois residents aged 18 to 64 years who were arrested for homicide in 2001. Controls were all other Illinois residents aged 18 to 64 years in 2001. Illinois criminal and juvenile record information for cases and controls was compiled for 1990-2000. Five definitions of previous record were considered (arrest, arrest for a violent crime, 5 or more arrests with at least 1 for a violent crime, felony conviction, and violent-felony conviction), each measured for 1990-2000 and for 1996-2000.

The population-attributable risk: the portion of homicide offenses that would be eliminated by a hypothetical intervention that reduced the offending risk of individuals with a record to the offending risk of those who lack a record.

For 1990-2000, 42.6% of 884 cases had at least 1 felony conviction compared with 3.9% of nearly 7.9 million controls, for a population-attributable risk of 40.3% (95% CI, 37.0%-43.8%); among cases, 71.6% had experienced any arrest from 1990-2000 compared with 18.2% of controls, for a population-attributable risk of 65.3% (95% CI, 61.6%-68.8%). For 1996-2000, the population-attributable risk among individuals with a felony conviction or any arrest was 31.0% (95% CI, 27.9%-34.2%) and 58.5% (95% CI, 54.9%-62.1%), respectively.

Interventions after arrest or conviction, such as supervised release, imprisonment, correctional programs, or bans on firearm possession, are targeted toward a group that has relatively high incidence of lethal violence, but they leave a large portion of the problem untouched.