A co-defendant of Georgia death row inmate Ray “Jeff” Cromartie, sentenced to be executed for murder, said recently he had no idea who pulled the trigger.

With the planned execution two days away, the co-defendant says he's been keeping a secret the past 25 years that makes him believe Cromartie most likely wasn’t the gunman.

“I keep hearing that Jeff Cromartie is the shooter and I know that is probably not true,” Thad Lucas wrote in an affidavit released Monday, claiming he overheard another man confess to the shooting. Lucas was the getaway driver for the 1994 store robbery turned shooting in South Georgia. He and fellow defendant Corey Clark testified for the state, avoiding the death penalty and murder charges.

At the time, Clark testified that Cromartie was the gunman. Cromartie said it was Clark.

Now Lucas, who is Cromartie’s half-brother, says he overheard Clark confess to the crime. He said he didn’t come forward before now because he feared no one would listen.

“I didn’t think saying anything about it would change the situation for (Jeff) or Corey and so I just tried to put the whole thing behind me,” Lucas wrote. “But over the last couple of weeks I have read about the case in the news and it has made me very angry because the story is not the truth of what really happened.”

Last month, Lucas said he wasn’t sure who shot and killed clerk Richard Slysz, 50, because he couldn’t see what happened from the car. Lucas now says his own past statements “helped hide the truth.”

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Clark, who has been wanted for an alleged parole violation since 2015, couldn’t be reached for comment.

Cromartie is scheduled to die at 7 p.m. Wednesday. His attorneys are fighting for new DNA testing that they say could prove Cromartie didn’t pull the trigger. Cromartie doesn’t deny involvement in the robbery, but he has maintained he wasn’t the shooter.

Generally speaking, Georgia’s party to a crime law could have made Cromartie eligible for the death penalty whether he pulled the trigger or not. But his attorneys said the party to a crime law doesn’t apply now because prosecutors explicitly argued at trial that Cromartie fired the fatal shots.

On Monday, Cromartie’s attorney Shawn Nolan said the defense team was preparing a filing for the U.S. Supreme Court, asking it to halt the execution based on Lucas’ statement.

“No court has ever heard or considered this new evidence of Ray Cromartie’s innocence,” Nolan said. “The state has denied his requests for DNA testing for years. Mr. Cromartie’s jury sentenced him to death based on their conclusion he was the shooter. If he was not the shooter, his death sentence is not valid and his execution must not proceed.”