Kirsten Mayer of Ropes & Gray.
Kirsten Mayer of Ropes & Gray. (Courtesy photo)

When Ropes & Gray took on George Perrot’s case, it seemed like a good opportunity for DNA exoneration. That is, until the firm found the DNA evidence was unusable.

Perrot had been convicted for a break-in and assault of an elderly woman that took place in the mid-1980s. Prosecutors had used forensic hair and blood analysis to tie him to the scene of the crime, but Ropes & Gray expected newer DNA analysis technology would show Perrot was innocent.

But they discovered the hair sample was lost long ago, and the blood sample was insufficient for testing.

The case suddenly seemed to be “a lost cause,” said Chris Fabricant, of the Innocence Project, who worked with Ropes & Gray.

“It was certainly a setback,” Ropes & Gray partner Kirsten Mayer said. But “fairly quickly after that we learned about the developments in the law in hair microscopy.”

Perrot’s team learned the FBI was questioning its own hair analyses from decades before. So they pushed to expedite the FBI audit in Perrot’s case and argued that the evidence used to convict Perrot was unreliable.

After a two-day hearing in January 2016, Perrot won a new trial, and was released from prison after 30 years in February 2016. “What is great about this case is [that] we were able to secure a new trial for Mr. Perrot, to free him, without DNA,” Mayer said.

Eventually, the FBI conceded that erroneous testimony or analyses were used in at least 90 percent of cases it reviewed.

Mayer’s team “had actually identified this as an error, as deeply flawed forensic testimony before the FBI letter,” said Lisa Kavanaugh, director of the CPCS Innocence Program, a unit of the Massachusetts public defender agency.

According to Ropes & Gray, hundreds of cases throughout the country are under review for similar hair testimony errors. But Perrot’s case was the first time a court had overturned a conviction based solely on the idea that the hair microscopy methods used were unreliable, said Fabricant.

“It’s one thing for the scientific community to understand that a forensic technique has been misused in court and it’s another thing for the proponents of that technique to admit it has been misused,” he said.

Kavanaugh said the way Ropes & Gray worked with the CPCS Innocence Program and Innocence Project could serve as a model. Prosecutors have appealed the decision, but Ropes & Gray built up a hefty record for the defense, she said.

“People are looking to the case and hoping it will provide guidance,” Kavanaugh said.