The Senate’s lawyers have filed documents in federal court to enforce a subpoena against the classified website Backpage.com as part of an investigation into sex trafficking on the Internet.  

The move by the Senate legal counsel was announced Tuesday by Sens. Rob Portman, R-Ohio, and Claire McCaskill, D-Mo., who lead the Permanent Subcommittee on Investigations of the Homeland Security and Governmental Affairs Committee.  

The action follows through on a 96-0 vote by the full Senate on March 17, to move forward with contempt proceedings.  

“[Backpage CEO Carl Ferrer] advances the novel proposition that the First Amendment not only provides a blanket protection allowing him to withhold all documents responsive to the Subcommittee’s subpoena, but also immunizes him from having to comply even with the basic duty of a subpoena respondent to search for responsive documents and assert privileges specifically thereon,” the Senate argues in a filing in federal court in D.C.  

“That proposition is incorrect. Because the Subcommittee’s subpoena does not infringe on First Amendment rights, Mr. Ferrer has no lawful basis to withhold the documents sought in the subpoena.”  

In a joint statement, Portman and McCaskill said the action has become necessary.  

“We have given Backpage.com every opportunity to comply with a lawful subpoena, but they have continued to stonewall our bipartisan investigation,” the senators said.  

“The Senate’s decision to bring civil action against Backpage will help us better understand how lawmakers, law enforcement, and even private business can more effectively combat the serious and heart-breaking crime of sex trafficking that thrives on an online black market.”  

Backpage has not yet responded to the legal filing.  

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