A randomized field experiment was used to evaluate the impact of efforts at post-arrest case enhancement by a special repeat offender unit of the Phoenix (Arizona) Police Department.
Repeat offender programs (ROP) involve cooperation between police and prosecutors to identify, convict, and incarcerate offenders who are likely to be committing crimes at very high rates. In this experiment, offenders were assigned randomly to two groups, referred to as "experimentals" and "controls." The experimentals were the offenders assigned as targets of the ROP whose cases were to receive special attention by the ROP unit. The criteria used as a basis for identifying potential ROP candidates were: current activity, substance abuse, lifestyle, probation failure, felony convictions, prior juvenile record, past informant activity, family background, and method of operation. Analysis of follow-up criminal history records for the first 6 to 18 months after the initial assignment showed that offenders designated as eligible for ROP treatment were in fact high-risk individuals. There was no significant increase in conviction rate for the experimental cases, but there were significant increases in the likelihood of commitment to prison and in the length of term imposed. 4 tables, 4 figures, 14 footnotes, and 20 references (Author abstract modified)