(KANSAS CITY, Mo., AP) — Three decades after being sentenced to death for the fatal stabbing of a fellow inmate, Reggie Griffin is officially a free man after a Missouri judge dismissed a murder charge against him.

Griffin, 53, has been out of prison since December while awaiting a new trial in the 1983 fatal stabbing of Moberly inmate James Bausley. On Friday, Randolph County prosecutor Mike Fusselman notified the court that he would no longer pursue that charge because there wasn’t sufficient evidence to find him guilty beyond a reasonable doubt.

“To not have this over my head is more than what words can describe,” Griffin told The Associated Press on Wednesday. “Now that it’s over, I’m going to try to put my life back together, to go on with my life.”

In the 10 months since an Adair County judge assigned to oversee the case released him on his own recognizance, Griffin has gotten a job and a new wife. He also occasionally speaks to young people about his experiences behind bars, hoping to deter them from making the same mistakes that put him in prison in 1981 for armed assault.

“They are intrigued by the conversations,” he said. “A lot of things go on in those prisons that I guess a person can only hear about. I can tell them firsthand because I lived it.”

Despite a lack of physical evidence, Griffin was convicted of stabbing Bausley and sentenced to death. He later received a life sentence after it was determined the state wrongly relied on the prior criminal record of another convict with the same name as an aggravated factor in pursuing the death penalty.

Griffin denied his involvement but was convicted after two inmates claimed to have seen him stab Bausley.

One of those inmates later recanted, saying he had not seen the attack and that the testimony he gave at Griffin’s trial was not true. The other inmate has died.

An appellate attorney also discovered that prosecutors had withheld a report that guards had confiscated a sharpened screwdriver from another inmate as he was attempting to leave the area where the attack took place.

The Missouri Supreme Court threw out Griffin’s conviction in August 2011, saying it was no longer “worthy of confidence.” Eight weeks later, Fusselman filed a new murder charge against him, saying new DNA evidence tied him to the murder weapon.

But on Friday, Fusselman acknowledged in court documents that he didn’t think there was enough evidence for a conviction.

DNA tests on the screwdriver “didn’t pan out,” he told The AP on Wednesday, and with several of the original witnesses either dead or not found by his office, he had no choice but to dismiss the case.

“It was challenging, a bit frustrating and a big learning case for me,” he said, adding that the decision wasn’t an easy one. “Once it’s made, I can’t come back and refile it. It’s done.”

In a statement issued Wednesday, Missouri Attorney General Chris Koster backed that move, saying it was “the appropriate and ethical decision at this time.”

Cyndy Short, one of Griffin’s attorneys, said Wednesday that the U.S. justice system is one of the best in the world but that cases like Griffin’s also show that it’s not perfect.

“We humans are flawed, and those flaws have led to wrongful arrests, wrongful convictions and, unfortunately, this situation where time and time again you see prosecutors holding onto cases, even when evidence of innocence is clear,” she said.