As Ropes & Gray counsel Ryan Malone got out of a cab and headed into the Washington, D.C., office of a client for a meeting on May 8, he felt his phone buzz. The call, it turned out, was one he’d been hoping to get since joining the firm in 2001 as a summer associate.

The caller was Ropes associate Michael Laufert, and he had news about a major development in a long-running pro bono case the two lawyers were working on: A Maryland state court judge, whose order had just arrived in the mail, had vacated firm client John Huffington’s convictions for committing a pair of 1981 murders. After more than 30 years in prison, Huffington might soon be a free man.

For Malone, a white-collar litigator based in D.C., the order validated 12 years of work on an assignment he took on even before graduating from University of Virginia School of Law and becoming a Ropes associate in 2002. "I’m the one who has been leading this now for a long time," says Malone, who talks on the phone at least once a week with the now-50-year-old Huffington. "It’s become quite personal."

Pro bono work on the case originated with David Stewart, a trial and appellate lawyer who sought it out in the mid-1980s while at now-defunct Miller, Cassidy, Larroca & Lewin to feed a desire to tackle a death penalty case. By 1988, Stewart had succeeded in having Huffington’s death sentence commuted to life in prison, and he brought the case with him when he moved to Ropes the following year. The firm has worked to clear Huffington’s name ever since.

In last week’s order, Frederick County circuit court Judge G. Edward Dwyer Jr.—who presided over the 1983 trial that ended with a jury convicting Huffington on two counts of murder—granted the petition for a writ of actual innocence the Ropes lawyers had filed on their client’s behalf in a maneuver made possible by a 2009 Maryland law allowing defendants to present fresh exculpatory evidence to reverse prior convictions. The Ropes team argued in its November 2010 petition that Huffington had been convicted of killing Joseph Hudson and Diane Becker, who were stabbed and shot to death following an apparently botched cocaine deal, based on faulty scientific evidence presented at trial by the Federal Bureau of Investigation. In siding with the petitioners and granting the writ, Dwyer also vacated Huffington’s convictions and ordered a new trial.

According to Dwyer’s ruling, the convictions relied heavily on two pieces of forensic evidence: bullets found at three locations that an FBI expert testified had come from the same box, which was used to tie Huffington to the scene of Hudson’s murder, and hairs found on the bed where Becker was slain that prosecutors said were "indistinguishable" from those on Huffington’s head. In the years since Huffington’s conviction, courts have ruled in other cases that the methods used to draw both conclusions are scientifically invalid.

The Ropes lawyers supplemented their petition in late 2011 after learning that the FBI had commissioned a report in 1999 that discredited agent Michael Malone, who presented the hair analysis at Huffington’s trial, as using methods that were flawed and unreliable. Ryan Malone, no relation to the discredited FBI agent, says he learned of the FBI’s report from a Washington Post reporter who wrote a 2012 story questioning why the FBI had failed to notify defendants and their counsel about the extensive doubts about Michael Malone’s methods.

Dwyer concluded in his order that "there is a significant possibility that the outcome of [Huffington's] case may have been different had the State not utilized the microscopic hair analysis evidence and Agent Malone’s testimony." Ryan Malone augmented the petition further in March by submitting DNA evidence showing that the hair found on Becker’s bed did not belong to Huffington.

State’s attorney Joseph Cassilly in Hartford County said Wednesday that his office has already asked Dwyer to reconsider the order, and has also appealed the decision. "I think the state’s going to prevail," says Cassilly, who has prosecuted the case since its inception. And if Dwyer’s order stands? "We’ll try it again." Even without the hair and bullet evidence, he insists, the state has a strong case. "The evidence against Huffington was, is, and always has been very convincing and overwhelming evidence."

Malone says the case—like his work on a Ropes team that helped free the men known as the West Memphis Three, who were imprisoned for more than 18 years after being found guilty of the alleged ritual killing of three young boys—is a testament to sticking with an assignment "even when there are a lot of setbacks along the way." (Last July, sibling publication The National Law Journal highlighted Malone’s work on the West Memphis Three case and a series of voter rights cases, pointing to the between 500 and 600 hours he spends a year on pro bono work.)

Stewart—the intial lawyer on the case, who retired from the Ropes partnership in 2007—takes a more pessimistic view. "The system is rotten," he says, pointing to what it took to prove the FBI’s evidence was unreliable. Even so, he says, "It’s wonderful to see justice in this case."

Malone adds: "When we first moved to test the evidence, the truth has never frightened us. It’s just been a long time for the truth to come out."