Broadly, in the judicial system, recidivism is a return to a correctional institution after a previous incarceration or a return to previous criminal behavior. In the mental health care system recidivism is the return to a previous dysfunctional attitude or behavior. In the welfare system recidivism is the return to cash assistance within a specified time of exit from the system.

But narrowly, as defined by law, the definitions are highly variable. Specifics that vary from one jurisdiction to another include such things as the type of repeat offense (lesser, equal, new, technical parole violations); where the repeat offense occurred; when the repeat offense occurred; how many months/years have passed since the last cash assistance; and how many times a patient is readmitted to a mental health facility in a given period of time.


Sources:
http://www.justiceconcepts.com/recidivism.htm
http://aspe.hhs.gov/hsp/leavers99/recidivism.htm
Websters, 1990