Kevin McCoy

USA TODAY

Silk Road Darknet mastermind Ross Ulbricht has lost his appeal of the life-behind-bars sentence he received for founding and running an online marketplace that made illegal drug purchases virtually a mouse click away.

A federal appeals court on Wednesday rejected arguments by defense lawyers that Ulbricht was deprived of his constitutional right to a fair trial and subjected to a "demonstrably unreasonable" punishment.

The ruling found no legal grounds for reversing Ulbricht's conviction or 2015 sentence for founding and operating Silk Road. Government evidence showed Ulbricht used the nom de net Dread Pirate Roberts — taken from The Princess Bride novel and movie — to preside over a criminal version of eBay that brought thousands of buyers and sellers together for Bitcoin-funded transactions in illegal drugs.

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The trial court "gave Ulbricht's sentence the thorough consideration that it required, reviewing the voluminous sentencing submissions, analyzing the factors required by law, and carefully weighing Ulbricht's mitigating legal arguments," Circuit Judge Gerard Lynch wrote in a 139-page ruling. "Under the law, we cannot say that its decision was substantively unreasonable."

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Accordingly, the three-judge panel affirmed both the trial result and punishment "in all respects."

Joshua Dratel, Ulbricht's lead defense attorney, declined to comment.

Operating from 2011-2013, Silk Road represented a quantum leap in illegal drug trafficking. Buyers and sellers conducteddeals collectively valued at roughly $183 million in an obscure area of the Internet via the Tor Network, a digital system that makes exchanges difficult to trace. All transactions were conducted in Bitcoin, an anonymous digital currency.

Federal investigators arrested Ulbricht in a San Francisco public library after learning his identity through Internet sleuthing. Arresting agents snatched a laptop from his hands, confirming he was operating the Silk Road site and communicating with an undercover investigator who had infiltrated the operation.

A jury of six men and six women convicted Ulbricht of conspiracy and other crimes after little more than three hours of deliberation in February 2015. The verdict came after prosecutors presented testimony about lives ruined by Silk Road drug trade, along with evidence that Ulbricht commissioned what he believed to be five murders-for-hire to protect his burgeoning creation from informants.

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Dratel argued that U.S. District Court Judge Katherine Forrest made numerous legal errors during the trial. They included denial of a defense motion to suppress evidence of Internet traffic to Ulbricht's home router that investigators obtained without a court-approved warrant.

Additionally, Dratel contended the defense was improperly blocked from presenting evidence that a former Secret Service agent who helped investigate Silk Road was himself investigated for stealing Bitcoins from the drug bazaar.

Along with rejecting those arguments, the appeals court ruled that Ulbricht's punishment was not unreasonable.

"Although we might not have imposed the same sentence ourselves ... on the facts of this case a life sentence was within the range of permissible decisions," the judges ruled.

Follow USA TODAY reporter Kevin McCoy on Twitter: @kmccoynyc

Ross Ulbricht Appeal Ruling