ST. PAUL  (AP) -- A federal appeals court hears oral arguments on whether Minnesota businessman Tom Petters deserves a new trial after being convicted of orchestrating a $3.7 billion Ponzi scheme.

Federal prosecutors and lawyers for Petters will go before a three-judge panel of the 8th Circuit Court of Appeals in St. Paul at 9 a.m. Thursday.

Petters' attorneys contend the judge at his 2009 trial prevented them from presenting their full defense to the jury that convicted him on 20 counts of fraud, money laundering and conspiracy. They wanted to delve deeper into the criminal past of a key prosecution witness who the defense claims masterminded the fraud without Petters' knowledge.

Federal prosecutors counter that the evidence of Petters' guilt was overwhelming.

Petters also seeks a reduction of his 50-year sentence.

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