Adults with a serious mental illness in the criminal justice systems: Study overview

Objective: The objective was to document the health, social service (HSS) and ,criminal justice contacts and associated expenditures of individuals in the study.

Methods: The County criminal justice data system was used to identify everyone who was in the jail during fiscal year (FY) 03-04. A variety of state (Medicaid, mental health authority) and local (County health, social service) data sets were used to identify which of these individuals had a serious mental illness (SMI). The period from 7/1/02 to 6/10/07 was divided into sixteen 90-day periods (quarters). The same data sets, along with state arrest and prison records, were used to identify, and locate in the appropriate quarter, the criminal justice and HHS contacts of each individual and the associated expenditures. Contacts and expenditures “per quarter” were calculated using the quarters during which each individual was residing in the County.

Results: Fourteen percent of all inmates had a SMI. The most common diagnoses were psychotic disorders (30%), bipolar I disorder (30%) and major depression (22%). On average, individuals were residing in the County for 14.4 (90%) of the quarters. They experienced one arrest for every three eligible quarters. The mean number of days in jail per quarter was 11; mean days in prison/quarter were 3.5.They experienced two mental health outpatient and one inpatient contact per quarter.

Conclusions: Individuals with a SMI represented a significant subpopulation of inmates in the County jail. Over the 4-year period, they were stable geographically and had extensive histories of criminal justice and HHS contacts.