Skip to main content

New policy raises the profile of DNA evidence in federal crime cases

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American


Federal law enforcement and prosecutors have received a mandate from the U.S. Department of Justice to use DNA identification whenever possible in investigating and prosecuting federal crimes. The move makes good on U.S. Attorney General Eric Holder's promise a year ago to use the power of DNA to exonerate the innocent as well as convict the guilty and is a reversal of a Bush administration policy that effectively induced some federal criminals to waive their right to DNA testing.

Holder issued two memoranda on Thursday. One memo directs federal prosecutors to seek DNA testing waivers from defendants and convicted criminals only "under exceptional circumstance" while the other memo outlines for federal prosecution offices and Department of Justice investigative agencies the requirement to collect DNA samples from federal arrestees and defendants.


On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.


Holder's mandates follow a yearlong review of the government's 2004 policy to get federal suspects to waive their right to DNA testing as a condition of pleading guilty. The review was initiated when the Justice Department realized the policy has been implemented inconsistently throughout the federal government. "Existing policy is too rigid to accommodate the facts presented by individual cases and does not promote careful consideration of whether a waiver is appropriate to the case at hand," according to Holder's memo.

Innocent people sometimes plead guilty to crimes because losing at trial would result in a harsher penalty, says attorney Peter Neufeld, co-director of the Innocence Project, an organization he founded in 1992 with Barry Scheck to assist prisoners who could be proven innocent through DNA testing (both lawyers were part of the O.J. Simpson defense team).

Under the Justice Department's previous policy, people who pled guilty forfeited their right to exonerate themselves at a later date using DNA evidence, a situation Neufeld characterizes as "mean-spirited." Whereas the Innocence Project has exonerated 261 people in the U.S. thus far, only one was a federal prisoner. Neufeld, however, stops short of predicting how much the change in DNA testing will impact the exoneration of additional federal prisoners.

DNA image courtesy of Richard Wheeler, via Wikimedia Commons

Larry Greenemeier is the associate editor of technology for Scientific American, covering a variety of tech-related topics, including biotech, computers, military tech, nanotech and robots.

More by Larry Greenemeier