U.S. flag

An official website of the United States government, Department of Justice.

Dot gov

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Https

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Disclaimer on Presented Research Results

NIJ is the research, development, and evaluation agency of the U.S. Department of Justice and is dedicated to researching crime control and justice issues.

Much of the content presented on this site results from NIJ-funded research, development, and evaluation projects. The content is not intended to create, does not create, and may not be relied upon to create any rights, substantive or procedural, enforceable at law by any party in any matter civil or criminal.

Opinions or points of view expressed on this site represent a consensus of the authors and do not necessarily represent the official position or policies of the U.S. Department of Justice. Any products and manufacturers discussed on this site are presented for informational purposes only and do not constitute product approval or endorsement by the U.S. Department of Justice.

Date Created: January 8, 2008