A major technology industry group reversed course and said it will support a bill designed to make it easier to sue websites that enable sex trafficking online. The bill has been a source of tension between the technology industry and Washington for months. The compromise comes just days after tech giants faced a hostile Congress in hearings examining their responsibility for Russian-bought propaganda advertisements on their sites.

The Internet Association, which counts Google, Facebook, Twitter and others among its members, said Friday that it now supports the Stop Enabling Sex Traffickers Act (SESTA) after a compromise that addresses fears that the bill would make Internet companies more vulnerable to litigation.

“Important changes made to SESTA will grant victims the ability to secure the justice they deserve, allow internet platforms to continue their work combating human trafficking, and protect good actors in the ecosystem,” Michael Beckerman, the Internet Association's president and chief executive, said in a statement.

(Amazon.com is a member of the Internet Association. Amazon chief executive Jeffrey P. Bezos owns The Washington Post.)

The bill would amend a key section of the Communications Decency Act, which insulates technology platforms such as Facebook and Twitter from being held liable for what their users post or say on their sites. But the bill's co-authors, Sens. Rob Portman (R-Ohio) and Richard Blumenthal (D-Conn.), have said that the current law makes it too easy for websites to facilitate sex trafficking of children and adults through ads and other posts without fear of repercussion. Executives from the classifieds site Backpage were called to testify before Congress in January to examine its role in underage sex trafficking.

“Removing the unwarranted shield from legal responsibility will save countless children from horrific tragedy, both physical and emotional,” Blumenthal said in a statement, praising Friday's compromise.

The changes include clarification that only companies that “knowingly” assist, support or facilitate sex trafficking may be held liable, the bill's sponsors said. It also makes clear that criminal charges are based on federal human-trafficking laws. Finally, it also permits state attorneys general to file civil suits in federal court on behalf of their residents against those who violate the federal human-trafficking law.

Removing technology-industry opposition clears a major obstacle for the legislation. “I’m pleased we’ve reached an agreement to further clarify the intent of the bill and advance this important legislation,” Portman said in a statement. 

Still, not all technology firms are on board. Engine, a trade group for start-ups, still opposes the bill, saying it remains unclear and “potentially penalizes startups for content” out of their control. “Platforms will likely be discouraged from taking steps to proactively fight trafficking for fear of exposing themselves to criminal charges and meritless civil litigation,” Engine policy director Rachel Wolbers wrote in a blog post.