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Search Warrants, Motions to Suppress, and "Lost Cases": The Effects of the Exclusionary Rule in Seven Jurisdictions

NCJ Number
Date Published
January 1991
33 pages
Data collected from a study of search warrant activity in seven cities located nationwide and interviews with key personnel in each criminal justice system were collected to examine the circumstances under which search warrants are used, what the outcomes are, how often motions to suppress physical evidence are made by defendants, and what the success rate and outcomes of these motions are.
Unlike previous research, this study analyzed actual search warrant applications, included information on the seriousness of the violation in cases where the exclusionary rule was invoked, and focused on individual cases. The results showed that motions to suppress evidence were successful in less than one percent of the primary warrants and motions were sustained for only two percent of all defendants in the sample. Twenty-one (1.5 percent) of the defendants were allowed to go free as a result of a successful motion; the offenders in these cases were charged with possession of cocaine, obscenity, fencing small amounts of stolen property, and possession of less than one ounce of marijuana. The findings indicate that the exclusionary rule, while not frequently invoked, serves as an incentive for police officers to heed fourth amendment limitations related to search and seizure. Officers in several jurisdictions had their warrants reviewed by prosecutors in order to ensure they met standards of probable cause. The authors conclude that the cost of the exclusionary rule in lost cases is minimal, that few criminals are freed as a result of successful motions to suppress evidence, and that criminals who are freed are those who have committed less serious offenses. 9 tables and 93 notes

Date Published: January 1, 1991