Georgia deputies used excessive force in the fatal police shooting of an unarmed mentally ill man and then made up a story  in order to justify the shooting, according to a new federal lawsuit.

The suit filed in U.S. District Court in Rome on Feb. 2 alleges that the two Bartow County deputies fabricated a story to make it seem like Darren Billy Wilson threatened them with a stick before he was shot on the afternoon of July 21, 2015.

The 47-year-old man had bipolar disorder and paranoid schizophrenia when deputies Anthony Parker and Nick Thompson answered a call of two men arguing in a wooded area in White.

When deputies arrived, they found Wilson by himself, wearing only his underwear, and yelling incoherently. He was saying something about "the devil," according to the lawsuit.

 Darren Billy Wilson

Credit: Brad Schrade

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Credit: Brad Schrade

What happened next is a source of dispute. The deputies said that Wilson charged at one of them with a stick and threatened him. Deputy Parker shot Wilson three times to diffuse the threat.

But the lawsuit alleges the GBI investigation identified no stick at the scene and the deputies gave multiple and conflicting accounts about the incident.

In one version,  the deputies said Wilson was holding the stick like a rifle, but police audio recordings captured the deputies screaming for him to show his hands, the lawsuit alleges. There was no mention on the recording to drop a gun or a stick, the lawsuit claims.

"They've given multiple accounts," said attorney Craig T. Jones, who is representing Wilson's two sons who filed the suit against the deputies. "They can't all be true."

"This guy was obviously mentally ill. He didn't pose a threat."

A phone call and email to Bartow County Sheriff Clark Millsap was not immediately returned on Monday.

Parker was cleared of any criminal wrongdoing in the case by Bartow County District Attorney Rosemary Greene last year.

The case is one of 11 fatal police shootings in Bartow County since 2010, according to an investigation by the Atlanta Journal-Constitution of police shootings across Georgia.