U.S. flag

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

What Every Law Enforcement Officer Should Know About DNA Evidence

First Responding Officers

Crime Scene Integrity: Compromising Evidence

Home  |  Glossary  |  Resources  |  Help  |  Contact Us  |  Course Map

Image of telephone at crime scene
National Institute of Justice (NIJ) (see reuse policy).

Be aware that all personal actions can compromise evidence at a crime scene. Therefore, evidence should only be moved if it will be lost or destroyed. Avoid touching anything, for example opening doors or windows, or using the telephone at the crime scene, unless absolutely necessary. These actions may contaminate valuable DNA evidence. If you must, for example, close a window because rain is pouring into the crime scene, DOCUMENT every action that is taken.

Back Forward