Those who believe juveniles get away with murder - or that the criminal justice system generally takes too soft an approach toward young men who commit violent crimes - will be pleased to know that Mark Farley Grant has been in prison for 25 1/2 years. He was arrested for murder when he was 14, tried and convicted when he was about to turn 15. A Baltimore judge sentenced Mr. Grant to life in prison. He's 41 years old now, a resident of the Department of Public Safety and Correctional Services since 1984. Yes, Maryland, we really do this. We have put teenagers (in this case, one who stood 5-feet-4 at the time of his crime) into our adult prisons and kept them there for many years. Some believe this is just. Others find it appalling. But however you feel about the practice of putting juveniles in prison, the matter of Mark Farley Grant demands attention because it is likely he did not commit the crime for which he has been so profoundly penalized. In fact, students at the University of Maryland Law School and their professors are convinced of it. They believe Gov. Martin O'Malley should commute Mr. Grant's sentence and release him from prison. What's more, they say they know who the real killer of Michael Gough is. Michael Gough, a teenager from West Baltimore, was shot to death on a winter evening in 1983 a few blocks north of Edmondson Avenue, apparently because he refused to give up the leather jacket he was wearing at the time. There were several robberies of jackets and athletic shoes in the early 1980s - envious boys with guns taking down their peers who flashed new leather on some of the city's toughest streets. Baltimore police charged Mark Grant, who was part of a group of boys in the area where Mr. Gough was shot, with his murder. During his trial and in the years since his sentencing, Mr. Grant claimed innocence. From prison, he wrote letters and filed petitions and motions, asking courts to review his case or modify his sentence. He did this, by and large, without the help of an attorney. All of his requests were denied. In 2004, he took his case to the Innocence Project at the University of Maryland Law School. The students of two professors, Renee Hutchins and Michael Millemann, took two years to research Mr. Grant's case before deciding to take it on. Their detailed report contains the following findings: 1. The chief witness against Mr. Grant testified falsely against him because relatives of the actual killer, who operated a drug gang in West Baltimore, took him to Leakin Park, held a gun to his head and vowed to kill him and his family unless he named Mr. Grant as the gunman. In 2006, the Innocence Project obtained an affidavit from the witness, who was 15 at the time of Mr. Gough's murder and a friend of the victim. In the affidavit, the witness names a man he says is the true killer. "Over the years," he says, "I have felt a great deal of guilt about falsely accusing Mark Farley Grant of shooting Michael Gough ... but felt that I had no other choice in light of the threats that had been made against me and my family." 2. Another boy confirmed seeing Mr. Grant in a nearby alley at the moment Mr. Gough was shot, making it impossible for Mr. Grant to have been the shooter. The trial jury never heard this testimony, according to the Innocence Project report. 3. Mr. Grant's co-defendant, originally suspected as the killer, ended up pleading guilty to attempted robbery, accepting a 10-year prison sentence and testifying against Mr. Grant. But this co-defendant failed a polygraph test prior to the trial, a fact that was never revealed to Mr. Grant's defense. The prosecutor in the case, now in private practice in Towson, acknowledged this failing in an affidavit for the Innocence Project in 2007. He also says that he never would have prosecuted Mr. Grant had he known that the key witness against him had been threatened. "Mark Grant did not kill Michael Gough," the report concludes. "There is now no question about the fact." With that, the Innocence Project asked Mr. O'Malley for clemency. That was more than a year ago. "We are aware of the case, and it is currently under review," a spokesman for Mr. O'Malley said when I inquired about Mr. Grant's petition. Of course, the governor, a former prosecutor, has made it clear he's not about to pardon many inmates. He has a law-and-order persona to maintain, so he's used the power of clemency only once - and that was for six ex-offenders convicted of minor offenses. Mr. O'Malley embraces the policy of a Democratic predecessor, Parris Glendening, who vowed no breaks for parole-eligible lifers unless they were old or gravely ill. Innocence should be a qualification, too, and the case of Mark Farley Grant should be a priority for any governor who cares about justice. Dan Rodricks' column appears Wednesdays and Sundays. He is host of the Midday talk show on WYPR-FM.