MARQUETTE (WWJ/AP) – A federal appeals court has upheld the convictions of a man and woman from Michigan’s Upper Peninsula who were accused of trying to blackmail actor John Stamos.

A three-judge panel in Cincinnati rejected challenges to the indictment Monday as well as claims that Allison Coss and Scott Sippola should have received a break at sentencing for accepting responsibility.

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They were sentenced to four years in prison in 2010 after a jury convicted them of conspiracy and using email to threaten a person’s reputation. Coss and Sippola threatened to sell old photos of Stamos with strippers and doing drugs to the tabloids unless he paid $680,000

The FBI said the photos didn’t exist.

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Stamos met Coss in Florida in 2004 and they became friends. She was 17-year-old at the time. Coss testified that Stamos snorted cocaine, sat nude in a hot tub with the scantily clothed teenager, and made sexual advances as they kissed while lying on a bed. He denied it.

Stamos, 47, starred on “ER” and “Full House” and recently played a dentist on Fox’s musical series “Glee.”

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