skip navigation


Register for Latest Research

Stay Informed
Register with NCJRS to receive NCJRS's biweekly e-newsletter JUSTINFO and additional periodic emails from NCJRS and the NCJRS federal sponsors that highlight the latest research published or sponsored by the Office of Justice Programs.

NCJRS Abstract

The document referenced below is part of the NCJRS Virtual Library collection. To conduct further searches of the collection, visit the Virtual Library. See the Obtain Documents page for direction on how to access resources online, via mail, through interlibrary loans, or in a local library.


NCJ Number: 222532 Find in a Library
Title: Searching for Equilibrium: The Tenuous Nature of the Outcome Test
Journal: Justice Quarterly  Volume:25  Issue:1  Dated:March 2008  Pages:54-71
Author(s): Robin S. Engel; Rob Tillyer
Date Published: March 2008
Page Count: 18
Type: Program/Project Evaluation; Test/Measurement
Format: Article
Language: English
Country: United States of America
Annotation: After summarizing the underlying assumptions of the "outcome test" for determining whether or not police engage in racial profiling in their stops/searches, this article argues that many of these assumptions are not met when applied to police search data, particularly the key underlying assumption, i.e., the principle of equilibrium.
Abstract: Advocates of the "outcome test" assume that if it can be shown that police stops/searches of drivers/pedestrians yield a disproportionately low rate of evidence "hits" in the resulting searches, then this is evidence that the police have made the stop for other than valid probable cause reasons, most likely because of the race/ethnicity of the suspect. This assumption fails because the outcome test has no way of controlling for all of the legitimate factors that might cause minority drivers to be searched at a higher rate than White drivers. It is therefore difficult to determine the true motivation behind a stop/search, regardless of whether evidence of a crime is found in the search. The inability of the outcome test (or any other statistical test currently used on traffic stop data) to determine the motivation of individual officers is related to Tomaskovic-Devey et al.'s (2004) description of the various types of racial bias. General equilibrium models are unable to distinguish between prejudices that motivate disproportionate stop/search rates based on various driver characteristics. For example, if police are stopping and searching higher proportions of minorities with low hit rates, it could be due to holding a stereotypical view that minorities are more likely to carry contraband rather than to racial bias. In fact, this belief may be true if measured under certain conditions, but untrue if measured under other conditions. 1 table and 28 references
Main Term(s): Profiling; Testing and measurement; Vehicle stops
Index Term(s): Mathematical modeling; Police discretion; Police policies and procedures; Racial discrimination; Search and seizure; Stop and frisk
To cite this abstract, use the following link:

*A link to the full-text document is provided whenever possible. For documents not available online, a link to the publisher's website is provided. Tell us how you use the NCJRS Library and Abstracts Database - send us your feedback.