WASHINGTON (AP) — Take the post down. Put it back up. Stop policing speech. Start silencing extremists.

That’s just a sampling of the intense, often contradictory demands facing tech companies and their social media platforms as they try to oversee internet content without infringing on First Amendment rights. The pendulum has swung recently toward restricting hateful speech that could spawn violence after a mass shooting in Texas in which the suspect had posted a racist screed online.

For Facebook, Google, Twitter and others, it’s a no-win whipsaw, amplified by a drumbeat of accusations from President Donald Trump and his allies that their platforms are steeped in anti-conservative bias. With lawmakers and regulators in Washington poring over their business practices, the tech companies are anxious to avoid missteps — but finding criticism at every turn.

“There’s a thin line between disgusting and offensive speech, and political speech you just don’t like,” says Jerry Ellig, a professor at George Washington University’s Regulatory Studies Center who was a policy official at the Federal Trade Commission.

Companies operating social media platforms have long enjoyed broad legal immunity for posted content. Under the 1996 Communications Decency Act, they have a legal shield for both for content they carry and for removing postings they deem offensive. Be it social media posts, uploaded videos, user reviews of restaurants or doctors, or classified ads — the shelter from lawsuits and prosecution has been a tent pole of social networking, and undoubtedly contributed to its growth.

But in the current climate of hostility toward Big Tech, that legal protection is getting a second look.

Legislation proposed last spring by Republican Sen. Josh Hawley of Missouri would require the companies to prove to regulators that they’re not using political bias to filter content. Failing to secure a bias-free audit from the government would mean a social media platform loses its immunity from legal action. It remains to be seen whether such a system could pass muster under the First Amendment.

Hawley’s legislation drew pushback from Michael Beckerman, who heads the major trade group Internet Association. He said it forces the platforms “to make an impossible choice: either host reprehensible, but First Amendment-protected speech, or lose legal protections that allow them to moderate illegal content like human trafficking and violent extremism. That shouldn’t be a tradeoff.”

The bias issue has dogged Silicon Valley for years, though there’s been no credible evidence. That’s done little to silence critics on the right, including at the White House, where Trump promised at a “social media summit” last month to explore “all regulatory and legislative solutions to protect free speech and the free-speech rights of all Americans.”

Some critics of Big Tech say the industry’s woes are partly of their own making. Having championed their commitment to free speech, the argument goes, their users weren’t prepared for the reality that content, at times, will be restricted.

“They were insisting they were neutral, or just technology platforms,” said Eric Goldman, a law professor at Santa Clara University and co-director of its High Tech Law Institute.