In October 2008, a jury found Stevens, R-Alaska, guilty of seven counts of making false statements on financial disclosure statements to hide about $250,000 in gifts and free renovations to his Alaska house.
Several months after Stevens' conviction, the Justice Department found prosecutors failed to turn over notes contradicting a witness and asked U.S. District Judge Emmet G. Sullivan to vacate the conviction. Sullivan erased the conviction and ordered an investigation.
Sullivan said in an order posted on his docket Monday the investigation was complete, The Washington Post reported. In the order, Sullivan wrote the investigation found the prosecution was "permeated by systematic concealment of significant exculpatory evidence which would have independently corroborated his defense and his testimony, and seriously damaged the testimony and credibility of the government's key witness."
The judge said investigators determined "at least some of the concealment was willful and intentional, and related to many of the issues raised by the defense" during trial.
The judge wrote the report recommended the Justice Department attorneys not be prosecuted for criminal contempt because the prosecutors did not "disobey an order that is sufficiently 'clear and unequivocal" to properly handle evidence.
Sullivan didn't say when he might tissue a final ruling on whether the prosecutors should face criminal charges.
Stevens, who lost his re-election bid shortly after being found guilty and whose charges were not dropped until April 2009, died in a small plane crash in Alaska in 2010.
The report was submitted under seal and won't be made public until it is reviewed by the Justice Department, attorneys for the prosecutors and Stevens' lawyers, Sullivan wrote.
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