He killed the man he accuses of raping him decades prior, and served years behind bars for the crime on a plea deal.

And now Clark Fredericks, a resident of Sussex County, is using that rock-bottom moment to urge molestation victims to speak up and "come out of their darkness."

"I've become an advocate for the changing of the statute of limitations law in New Jersey, which we just passed," Fredericks told New Jersey 101.5. "I've become a motivational speaker, speaking at colleges, high schools. I went back to the county jail where I was housed."

Fredericks' drugs- and alcohol-laden past, which came to a head when he repeatedly stabbed and killed the man who had served as his Boy Scout leader and who Fredericks says raped him when he was 12 years old, will play out for the nation to see on Oct. 6 at 7 p.m., as part of the "Killer Motive" true crime series produced by NBC and airing on the Oxygen channel.

Fredericks said he "did everything wrong" — not just the 2012 killing of Dennis Pegg, to which he ultimately pleaded guilty on a deal that reduced his murder charge to passion provocation/manslaughter — but in keeping the traumatic incident a secret for decades.

He was released in 2017. According to NJ.com, which reported on his guilty plea and sentencing in 2015, the judge, prosecutor and defense attorney all agreed the evidence showed Pegg had abused him as a child — but the judge still declined to reduce his charge to a third-degree offense and impose a four-year sentence, as the defense had requested. Instead, the judge imposed the minimum sentence for a passion provocation murder — five years — and Fredericks got credit for time already served.

To this day, Fredericks himself continues to describe the killing as a "murder," even though he was never convicted of that particular charge.

Freedericks is hoping the television program includes his path to redemption. The 53-year-old has embarked on a speaking career, hoping "no one becomes so broke and disillusioned that they would commit murder."

"By sharing my story, I just try to get other people to open up," Fredericks said. "Secrecy is what killed me, secrecy is what kills others — the shame and the secrecy."

Fredericks said he ran into Pegg at a deli about three decades after the alleged molestation. According to Fredericks, Pegg had a young boy with him, and the boy was calling Pegg the same nickname he had insisted Fredericks call him when he was a young boy.

"I had this animal on my mind for 24/7 after encountering him in that deli with that boy. I couldn't shake it," Fredericks said. "That's how I was living until the day I murdered him."

Fredericks spent four-and-a-half years in prison for the crime. He remains on parole until the end of this year.

Gov. Phil Murphy signed a measure into law in May that extends the window during which a sexual assault victim can file civil lawsuits against alleged abusers and the institutions where they worked.

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Contact reporter Dino Flammia at dino.flammia@townsquaremedia.com.