DETROIT (AP) — A Michigan prisoner has persuaded a judge to throw out his burglary conviction, overcoming long odds by serving as his own lawyer in an appeal of a case that rested solely on his DNA being found on a soda bottle in a beauty shop.

Gregory Tucker, 65, argued that the DNA wasn’t sufficient on its own to convict him in the 2016 break-in near Detroit, citing U.S. Supreme Court rulings about evidence.

U.S. District Judge David Lawson agreed that the case against Tucker was thin.

“Any inference that (Tucker) must have deposited his DNA on the bottle during the course of the burglary was pure speculation unsupported by any positive proof in the record,” Lawson wrote in the Aug. 1 ruling.

Anne Yantus, a lawyer who spent 30 years at the State Appellate Defender Office and who isn’t connected to the case, said what Tucker managed to do isn’t easy.

“I’m just impressed that this is a man who had enough confidence in himself and his legal skills to represent himself with a habeas claim,” said Yantus, referring to habeas corpus, the Latin term for a last-ditch appeal that lands in federal court long after a conviction.

The petitioner tries to argue that a guilty verdict violated various protections spelled out in federal law. Success is extremely rare.

Tucker was accused of breaking into a beauty shop in Ferndale in 2016. Supplies worth $10,000 were stolen, along with a television, a computer and a wall clock.

Tucker was charged after his DNA was found on a Coke bottle at the crime scene. Authorities couldn’t match other DNA on the bottle to anyone.

Speaking from prison, Tucker told The Associated Press that he was “overwhelmed” by Lawson’s ruling. He said he has no idea why a bottle with his DNA ended up there.

“A pop bottle has monetary value,” Tucker said, referring to Michigan’s 10-cent deposit law. “You can leave a bottle on the east side and it can end up on the west side that same day.”

His victory hasn’t meant he’s been freed. Tucker is still serving time for a different conviction and can’t leave prison until the parole board wants to release him.

Prosecutors, meanwhile, aren’t giving up. The Michigan attorney general’s office said it plans to appeal the decision overturning Tucker’s burglary conviction.