(WSBT) He changed his plea for illegally selling the gun used to kill a South Bend police officer. Now, in an exclusive interview with WSBT, Ronald Wedge speaks publicly for the first time.

Seventy-one year-old Ronald Wedge admitted in federal court Tuesday to falsifying information about the sale of a handgun to Scott Barnaby on April 21, 2007.

Two days later, Barnaby used that gun to shoot and kill South Bend Police Corporal Nick Polizzotto and wound Patrolman Michael Norby outside his room at the Wooden Indian Motel. Barnaby was also killed in the shootout.

After changing his plea to "guilty" on two of the three counts against him, Wedge's trial — set to begin next week — has been canceled.

Court documents show Wedge admitted to changing the date on the federal background check form that Barnaby filled out, and to marking that Barnaby had shown him the required forms of ID. Our news partners at the South Bend Tribune say Wedge told the judge Barnaby had instead shown him a voter registration card or a birth certificate.

It all happened on April 21. Like so many Saturday afternoons since he became a licensed firearms dealer in 1974, Ronald Wedge was working a gun show in St. Joseph County, showing potential buyers stock from his Hole-in-the-Wall Gunworks store in Bristol. That's when he says Scott Barnaby walked up, and asked to buy a .22 caliber pistol.

"It just didn't click when I sold the gun," Wedge told WSBT in an exclusive interview following his plea deal. "All of a sudden I realized, 'Man you screwed up.'"

Wedge says the following Monday, April 23, he called every "Barnaby" listed in the phone book to demand the gun back.

Twelve hours later, both Scott Barnaby and Corporal Nick Polizzotto lay dead.

"I'm bound to make mistakes," Wedge said. "I've never done that with a gun before, and I don't know what possessed me to do that. I just forgot."

When asked if he believes he should serve time behind bars for what he pleaded guilty to, Wedge replied "No, I don't. Because of my record. I've done the best I could for the ATF [Bureau of Alcohol, Tobacco and Firearms] and put money in their pocket."

But when reminded of his earlier statement stating 'I made a mistake,' Wedge replied, "Yes. But it was the only mistake I ever made in my life."

Still, Wedge later admitted he made another mistake, by lying about what he'd done, and now he says he's paying for that "mistake" too.

He says his Bristol gun shop has been liquidated and his family is now living on food stamps, relying on donations from friends to help get by.

"I've gotten so much support from people, it's just amazing," Wedge said.

Even so, Wedge says most people he's talked to assume he's a bad person. He says he's not, and says he's just being misunderstood.

He points to a newspaper article published four years ago, hailing him as a hero, after he swam out to rescue two stranded swimmers in Lake Michigan.

Now, he says he's been fired from his job as a game usher at Notre Dame, and has been shunned by some friends he once served with in the Army's 101st Airborne Ranger Division prior to the Vietnam War.

He says he now feels like the one who's drowning.

His one hope now, he says, is to pay his debt to society and leave a clear message in the wake of tragedy.

"I just hope the police officer's family can find a small spot in their heart for me," he said, choking back tears. "I'm very sorry."

Corporal Polizzotto's brother Tony Polizzotto issued the following statement in response to Wedge's plea:

"The plea does bring us some additional closure, and it's a good thing that he's standing up and taking responsibility for his actions. How should he be sentenced? That isn't up to us. We'll let the judge decide that. We know that no matter what it is, even if he's truly sorry, he still has to live with what he did."

Assistant U.S. Attorney Donald Schmid has agreed to drop one of the three counts against Wedge and recommended a lighter sentence in exchange for the plea.

Wedge now faces up to 10 years in prison and a $500,000 fine when he's sentenced in early December.