The US House of Representatives on Tuesday approved legislation intended to curb online sex trafficking by holding website operators more accountable for their users' activities.

The measure, passed by the House 388-25, would amend a section of the Communications Decency Act by including the Stop Enabling Sex Traffickers Act, S. 1693. The bill would make it a crime to operate an internet platform with the intent of promoting prostitution.

"We must put an end to modern day slavery here in the United States," House Speaker Paul Ryan said in a statement before the vote. "And that starts with stopping the manipulation and exploitation on the internet."

The bills arose to combat online sex trafficking often perpetuated though sites like Backpage.com, which has classified advertising where people can solicit prostitutes. Many of the people on this website are trafficked women and children, according to the National Center on Sexual Exploitation.

The bill would give sex-trafficking victims more power to sue websites that knowingly support sex trafficking. Supporters say the legislation will help curb the growing epidemic of online sex trafficking that often involves children, while opponents argue it could expose tech companies to costly lawsuits and infringe on free speech.

"Facing the threat of extreme criminal and civil penalties, web platforms large and small would have little choice but to silence legitimate voices," the digital rights group Electronic Frontier Foundation warned last week. "Platforms would have to take extreme measures to remove a wide range of postings, especially those related to sex."

Several major internet companies were initially reluctant to weaken the legal protections against liabilities for the activities of their users. But the Internet Association, which represents including Google and Facebook, among many others, threw its support behind the bill in November.

Similar legislation is still pending in the Senate, where it has substantial support. After Senate passage, it will still need to be signed into law by President Donald Trump.

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