The authors used a randomized field experiment to evaluate the impact of efforts at post-arrest case enhancement by a special repeat offender unit of the Phoenix Police Department. Analysis of case disposition patterns showed no significant increase in conviction rate for the experimental (ROP) cases but revealed significant increases in the likelihood of commitment to prison and in the length of term imposed. These increases appeared attributable to the ROP officers' success in developing additional charges against the defendants and documenting their prior records.

Originally published in: Justice Quarterly, v. 8, no. 2, June 1991, pp. 141-168.

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