The CEO of a popular classified ads website that lawmakers say is a hub for underage sex traffickers refused to appear before a Senate subcommittee Thursday, the first time a witness has refused a Senate subpoena in at least 20 years.

Backpage.com CEO Carl Ferrer declined to appear before the Senate Homeland Security and Governmental Affairs Subcommittee on Permanent Investigations Thursday to testify on sex traffickers’ use of his website to sell underage children for sex acts in the U.S.

“We had hoped Mr. Ferrer would be here, but he has refused to come,” subcommittee chair and Ohio Republican Rep. Rob Portman said at the conclusion of Thursday’s hearing. “This is truly extraordinary.”

Ferrer has been under subpoena by the subcommittee since Oct. 1, and since then, requested through his attorneys multiple times that he be excused for business traveling plans, since he indicated he would only plead his right not to self-incriminate under the Fifth Amendment.

“This subcommittee would respect any valid assertion of Fifth Amendment privilege, but there’s no privilege not to show up,” Portman said, describing Ferrer’s refusal to appear as “a clear act of contempt.”

“If Backpage fails to change course and comply with the subcommittee’s subpoena, the appropriate next step is to pursue contempt proceedings. This is a step the Senate has not taken in 20 years,” Portman continued, adding the committee itself hasn’t taken such action in 30 years, and that it will weigh in the next few days whether to refer Backpage to the Justice Department for criminal contempt.

In his opening statement Portman said Backpage lawyers recently told the committee the site hadn’t even bothered to search for and produce documents the committee requested as part of its investigation.

“This isn’t an exercise in having a hearing, this is an exercise in making sure that we have done everything in the law to protect children,” ranking Democrat and Missouri Rep. Claire McCaskill said. “So we will be careful and cautious about using the procedures available to us, but we will use them.”

According to Yiota Souras, senior vice president and general counsel for the National Center for Missing and Exploited Children (NCMEC), 71 percent “of all the child sex trafficking reports submitted by members of the public” to the center’s CyberTipline “relate to Backpage ads.”

Backpage has until now defended itself under the Communications Decency Act (CDA), stating it is only a publisher of content on its website, and as such, is not liable for any illegal activities that take place as a result of ads for prostitution.

Prosecutors, lawmakers and NCMEC cited questionable activity by Backpage moderators, including evidence of editing ads to keep them from running afoul of the law, refusing to implement photo DNA software to automatically flag and pull down ads and scrubbing metadata from ads it turns over to NCMEC, which would help authorities track down sex traffickers.

Souras pointed out Backpage requires certain identifying information, such as a telephone number or email address, for other private ads for the sale of items. It requires no such criteria for sex ads. While NCMEC’s general counsel conceded Backpage came to the organization early on regarding the issue, Souras said it appeared Backpage was more interested in soliciting a good public image from NCMEC rather than taking tangible action on sex ads featuring children.

“Even when an escort ad is reported by families as containing images of their child, Backpage often does not remove the ad from public view,” Souras said. “Instead, the reported ad remains live on Backpage.com where potential customers can continue to purchase the child for rape or other sexual abuse, even though Backpage is now on notice that the ad potentially involves a child.”

Washington Deputy Attorney General Darwin Roberts said the state tried to pass a law in 2012 to criminally punish anyone facilitating the publishing of sex ads featuring minors — a law Backpage led opposition to early on, and was enjoined by the U.S. District Court in Seattle for preempting the CDA and over-broad language on First Amendment grounds.

Roberts added Backpage is likely exceeding the grounds of exemption from prosecution under CDA “by actually participating in drafting the ads, by making themselves a go-to location for ads advertising prostitution among such sites, and by crafting the message thats being sent to try to keep it so that it doesn’t appear to involve child trafficking.”

“Earlier you said that a mother finally sent them an email saying, ‘For God’s sake, she’s only 16’,” Portman told Souras. “So for all of us who are parents, who are grandparents, think about that — ‘For God’s sake, she’s only 16.’ And yet they refused to pull the ad.”

“Not being able to provide that information to law enforcement means you can’t find many children who otherwise could be able to be found,” Portman continued. “And the heartbreak of knowing that information is out there somewhere, and yet a supposedly legitimate commercial concern won’t provide you the information, or provide it to law enforcement to be able to find your child — to me this is what this hearing’s really all about.”

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