The Utah Court of Appeals threw out a Midvale man’s aggravated assault and burglary convictions Thursday amid questions about the accuracy of forensic evidence, specifically a bloody handprint.
A partial palm print on a pillowcase was the only piece of evidence tying the then-33-year-old Robert M. Sheehan to a December 2006 attack that left a woman seriously injured in her home, according to the ruling released Thursday.
The victim identified another man as the attacker, a co-worker whom she had invited into the house and was still there at the time of the attack, according to Thursday’s ruling.
But as police investigated, they eliminated the co-worker as the attacker and focused on Sheehan, in part because he had lived with the victim for eight months in 2005. When his house was searched, officers found a dress and two pairs of underwear that belonged to her.
When police asked if Sheehan was her attacker, the victim said no.
At trial, prosecutors relied "almost entirely" on the State Crime Lab’s analysis that the partial palm print belonged to Sheehan, according to the ruling. The victim did not testify, but prosecutors did call the two State Crime Lab scientists who worked on the case, one of whom testified that to his knowledge, he had "never made an error."
But the judge did not allow another expert to testify who could have shed doubt on whether the palm print actually belonged to Sheehan: Simon Cole, who has written extensively about inaccuracies in fingerprinting.
The judge decided that because the print was admitted as evidence, testimony questioning the science wouldn’t be allowed. But the appeals court disagreed, ruling that just because the state’s forensic scientists are reliable doesn’t mean a contradictory expert is unreliable. It’s up to the jury to decide, especially in a case where the prosecution relied so heavily on a particular piece of evidence, the appeals court ruled.
"If Dr. Cole had been allowed to testify and challenge the reliability and validity of the State’s expert witnesses, the jury could have easily found that reasonable doubt existed ... especially given [the victim’s] earlier identification of a different perpetrator," Judge Michele Christiansen wrote in Thursday’s ruling.
Sheehan was sentenced to five years to life in prison on the aggravated burglary and aggravated assault in 2009. Thursday’s ruling will give him a new trial; no date has yet been set.
Copyright 2014 The Salt Lake Tribune. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.