NEW YORK (CBSNewYork) — Tuesday is sentencing day for disgraced upstate New York self-improvement guru Keith Raniere, who was convicted of turning women into sex slaves in his organization NXIVM.

In a last ditch effort to delay sentencing, a group of supporters, who call themselves the “NXIVM Five,” allege to have proof of evidence tampering, CBS2’s Alice Gainer reported Monday.

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“We have submitted a letter to the judge sharing with him an independent report corroborated by multiple experts,” a group member said.

On Friday, a federal judge denied Raniere’s second request for a new trial.

Raniere, 60, was convicted of multiple crimes including racketeering and sex trafficking after a six week trial in 2019.

Founded in Albany in 1998, NXIVM offered self-help courses through its executive success programs. Eventually, it opened centers across the U.S., Mexico and Canada.

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In 2015, prosecutors said Raniere added a secret, female-only society to NXIVM called DOS, or “The Vow.”

In an HBO docuseries, former DOS members claim there were masters and slaves within the society. Some were selected to be sexual partners for Raniere, and had to fork over collateral, like nude photos, and ask for permission to eat.

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Prosecutors said actress Allison Mack was at the top of DOS. Some members were also branded with Raniere’s and Mack’s initials.

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Former NXIVM member Barbara Bouchey will be one of many expected to deliver a victim impact statement at Raniere’s sentencing.

“We’re only allowed 10 minutes in court to speak our victim impact statement. That’s 20 years in 10 minutes,” Bouchey said. “Really looking forward to tomorrow coming and going, and for it to be over and finally be able to close this book and put it behind me, and move forward.”

Prosecutors had no comment about the accusations of tampering. A lawyer for Raniere did not get back to CBS2 before this report.

Raniere faces 15 years to life in prison.

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