Criminal Law Evidence Legal Topics

Did Unreliable DNA Evidence Convict an American Student of Murder in Italy?

Update: An Italian appeals court threw out Knox’s murder conviction on October 3, 2011 and ordered her freed after 4 years in prison.

Amanda Knox was studying in Italy when her life changed forever: She was convicted of murdering her roommate. But there may be a glimmer of hope for Amanda, because two independent, court-appointed experts dispute as unreliable the DNA evidence that was crucial to the prosecution’s case. Sometimes a case can all come down to just how the evidence is collected and handled.

In their report to the appeals court in Italy, the experts were reportedly “scathing” in their criticism of the reliability of the DNA evidence that led to Knox’s conviction. The experts claimed the police neither followed the procedures for ­inspecting a crime scene nor the standards for collecting and bagging exhibits.

This report is obviously great news for Knox’s defense team, who is reported by to be “confident the 24-year-old will be home in time for Christmas.”

This case makes it clear that responding law enforcement officers must take great care with any object associated with a crime that may have biological evidence deposited on it, and all attorneys involved in the case need to confirm that such care was taken.

A police officer can contaminate evidence by touching it or even by breathing on it, spreading microscopic DNA from one object to another, or by packaging evidence together with the same result. Officers should follow the suggestions in the Department of Justice (DOJ) publication, First Responding Officers: What Every Law Enforcement Officer Should Know About DNA Evidence, when collecting, packaging, and transporting evidence, or risk the results being compromised.

Attorneys on both sides of the case need to pay careful attention to the DOJ’s recommendations. Defense counsel should consider developing a cross-examination based on the recommendations. The proponent of DNA evidence can head off such defense attacks by establishing requisite care at the outset.

For everything you need to know about DNA evidence, go to CEB’s Scientific Evidence and Expert Testimony in California. Also check out my earlier blog post 10 Tips for Attacking DNA Evidence.

© The Regents of the University of California, 2011. Unauthorized use and/or duplication of this material without express and written permission from this blog’s author and/or owner is strictly prohibited.

2 replies on “Did Unreliable DNA Evidence Convict an American Student of Murder in Italy?”

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