The U.S. Department of Justice has issued a subpoena to the libertarian news site Reason, calling on them to provide information about six users who threatened Judge Katherine Forrest. Forrest is the federal judge who sentenced Ross Ulbricht to life imprisonment without parole for his role in founding and operating the Silk Road online drug marketplace.

“It's judges like these that should be taken out back and shot,” wrote a user named Agammamon in a string of comments beneath a story on Ulbricht's sentence. The comments have since been deleted. 

“It's judges like these that will be taken out back and shot,” said another, named Alan.

“Why do it out back? Shoot them out front, on the steps of the courthouse,” said a third comment, this one from the username Cloudbuster.

The subpoena – sent last week and published Monday by Popehat blogger Ken White – demands that Reason provide the six users' phone numbers, email addresses, IP addresses, billing information, their computer IP addresses and information on what devices they used to access the website. It cites a section of the U.S. criminal code that prohibits “mailing threatening communications” against a judge, a crime punishable by up to 10 years in prison.

Whether the Reason commenters were serious about their threats is up for debate, but there's no doubt that Judge Forrest infuriated much of the online libertarian community by sentencing Ulbricht to spend the rest of his life behind bars. Even before his identity was revealed, the 31-year-old Texas native became an online icon by designing the Silk Road as an eBay for the black market. Users bought and sold drugs of all kinds by trading in bitcoins, keeping their identities secret and, in Ulbricht's case, posting long anti-government rants equating drug sales with freedom of expression.

“We command you that all and singular business and excuses being laid aside, you appear and attend before the grand jury of the people of the United States,” states the subpoena, signed by U.S. Attorney Preet Bharara and Assistant U.S. Attorney Niketh Velamoor. “The Government hereby requests that you voluntarily refrain from disclosing the existence of the subpoena to any third party.”