ST. TAMMANY, La. — Warning: Some of the details of the allegations in the story are graphic and disturbing

Life has not been easy on Mark Finn and his tough exterior shows it. The self-admitted career criminal has “psycho” tattooed on his neck, a clear sign he is not to be messed with in or out of prison.

But Finn claims that steely exterior houses a dark secret. At age 6, Finn said a close family friend began molesting him and over a period of six years, the touching allegedly turned to rape.

Finn claims that close family friend is former St Tammany Parish Sheriff Rodney “Jack” Strain.

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“People who do know me, they know I’m telling the truth,” Finn said.

Just four days out of his latest stint in prison, Finn, now age 49, began to break his silence about the alleged abuse on social media, later sitting down for an exclusive interview with WWL-TV and partner newspaper The New Orleans Advocate.

Strain is seven years older than Finn, meaning the alleged abuse began when Finn was 6-years-old and Strain a teenager.

Finn choked up with tears clouding his eyes when describing what he says happened, but the details he provides are far from fuzzy.

“Sick stuff and I remember this stuff. I remember everything,” Finn said.

He tells of yarn strung around two nails, one on the door, the other on the door jamb of a bedroom of Strain’s parents’ Abita Springs home that he said Strain asked to tie shut before their encounters.

“When I come in the room, that was part of the deal, he'd have me, he had these spools of yarn, one of them pink, one of them was green. If there wasn't a thread there, he'd cut one,” Finn said.

But according to Finn, the abuse wasn’t confined to the bedroom. He said it happened in the barn, in the pond, in vehicles and other places around the Strain family property.

He said Strain poured lotion and oil on his buttocks and describes seeing blood in the bathtub when he cleaned off.

Strain’s attorney, Billy Gibbens, said the former sheriff strongly denies Finn’s accusations.

“He’s alleging that something happened more than 40 years ago that never happened,” Gibbens said. “He’s fabricated this and it’s completely false. He’s a career criminal who’s been in jail most of his life. The last time Jack saw him he was working as a trusty at the St. Tammany Parish Jail. He has zero credibility.”

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The emotion in Finn’s words is raw when talking about the allegations and he said he is desperate for closure. Despite telling state and federal investigators numerous times about the alleged abuse, Finn said he wants the world to know what he says happened.

Finn said he is one of the alleged victims at the heart of the sex crimes investigation into Strain. Sources with knowledge of the case have told WWL-TV and the New Orleans Advocate there are at least three other victims involved as well.

Current St. Tammany Sheriff Randy Smith confirmed the investigation, adding it stemmed from the federal corruption probe.

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“That right there is sick what happened to me. And I'm not the only one. I just hope justice is done soon so I can put this behind my life and move forward so it doesn't happen to somebody else,” he said.

Strain has not been charged with any crime but charging documents in a related public corruption probe do name the former St Tammany Parish Sheriff as the target of that investigation.

Finn said “Boo boo,” as he called Strain, made his time in prison easier, allowing him to stay at a makeshift apartment above the STPSO tool shop at the Slidell work release facility.

Many in the community refer to that work release facility as ‘the halfway house.’

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“I didn't live bad at the halfway house. But it still doesn't take what he did to me. You could give me everything in the world but let me tell you one thing, I’m not gonna be happy until he is locked up,” Finn said.

While Finn said the worst of the alleged abuse stopped around age 12, he claims Strain attempted sex twice while he was incarcerated in the work release program in the late ‘90’s.

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“He came and picked me up in the halfway house, brought me to a camp in Abita. Put his hand on my leg and then grabbed my crotch. And I grabbed his hand and told him I don't do that. And he stopped,” Finn said.

Again, Strain strongly denies the allegations.

He describes a similar encounter a couple of years later when Strain allegedly picked him up to go fishing.

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Finn said he first made the allegations against Strain when a US Marshal, an investigator for the IRS and an FBI agent came to interview him while he was incarcerated in Livingston Parish in 2017. Since, he said he’s had numerous meetings with state and federal prosecutors about the allegations.