Issue in focus: Evidence Preservation


On May 14, 2008, Colorado Gov. Bill Ritter signed a new evidence preservation law, making his state the 24th nationwide to address the preservation of evidence in at least some crimes.

“This law is a major step forward for justice in Colorado,” Innocence Project Policy Analyst Rebecca Brown told the Fort Collins Coloradan. “This evidence can provide clear answers to lingering questions about innocence or guilt.”

Read a May 15, 2008, news story on the new Colorado law


Efforts to improve evidence preservation in Colorado heated up this year after Timothy Masters was released in January. He served nine years in prison for a murder he has always said he didn’t commit, and some evidence connected to his case had been saved while other items were destroyed. New DNA testing on the retained evidence pointed to Masters’ innocence and led police to reopen their investigation of the murder. A Denver Post investigative series on evidence preservation efforts nationwide also brought the issue to the public eye.

View the multimedia series here


Preservation in Your State

For a map of the 35 states with evidence preservation laws in place and background on each of these laws,

click here


Don’t like what you find on our map?

Get involved today to secure better evidence preservation practices in your area


Marvin Anderson: Evidence Found

Marvin Anderson was exonerated in 2002 after serving 15 years in prison and 4 years on parole for a rape he didn’t commit. The Innocence Project accepted Anderson’s case in 1994, and initial searches for biological evidence were unsuccessful. Anderson’s Innocence Project attorneys were nearly ready to give up hope when a swab from the rape kit was discovered in the files of a lab analyst so meticulous that she preserved samples in her notebooks – a practice that didn’t follow her lab’s policy but that eventually led to proof of Marvin Anderson’s innocence.

After Anderson was proven innocent and exonerated, Virginia Gov. Mark Warner ordered the state lab to systematically test evidence from ten percent of more than 300 cases from the files of Mary Jane Burton, the analyst whose unorthodox policy led to Anderson’s exoneration. DNA tests were performed in 31 cases, including 29 where convictions had been secured, and two more men – Willie Davidson and Phillip Thurman – were exonerated. Burton’s files have now been involved in five exonerations in all, and a review of all of her files is ongoing.

Watch a two-minute video about Marvin Anderson’s case here


In other recent cases, including the exonerations of Alan Newton and Anthony Capozzi in New York, evidence was requested for years before it was located by officials. In both of these cases, proper storage and cataloguing could have allowed DNA testing to proceed much earlier.

The Destruction of Hope

The 216 people exonerated by DNA evidence represent a tiny fraction of wrongfully convicted Americans because only about 5-10 percent of convictions in this country involve biological evidence and even in those cases evidence is often lost or destroyed before post-conviction DNA testing can happen. A preliminary review shows that one-third of cases closed by the Innocence Project were closed because of lost or missing evidence.

More Resources

Read more about evidence preservation in our Fix the System section


Read news on the new Colorado evidence preservation law


Read the groundbreaking Denver Post series: “

Trashing the Truth

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