Rebellious House Republicans on Wednesday turned back an effort to renew an anti-terror surveillance law that’s been used in the past to spy on Americans, leaving its fate up in the air less than 10 days before it’s set to expire.

The fight over the Foreign Intelligence Surveillance Act — and particularly the post-9/11-era spying provision Section 702 — has pitted both Republicans and Democrats worried about civil liberties against a similarly bipartisan group that sees the law as a crucial tool in the country’s national security toolbox.

Nineteen Republicans bucked party leaders and voted against allowing the renewal bill and amendments to be debated on the House floor, stalling its progress with a 193-228 vote.

“The constitutional liberties of Americans have to come first. We don’t bend the constitution for anything,” said Rep. Bob Good (R-Va.) after the vote.

Hours before the vote, former President Donald Trump cheered the opposition on social media, calling on lawmakers to “KILL FISA.”

FISA authorizes surveillance programs against foreign individuals abroad. But in eavesdropping on those communications, exchanges with U.S. citizens can also be captured — meaning, critics say, the program effectively allows for “backdoor” searches of Americans’ communications.

Tuesday’s outcome was another defeat for embattled House Speaker Mike Johnson (R-La.), who attempted unsuccessfully to tread a thin line between the competing FISA factions in his own conference.

Firebrand Rep. Marjorie Taylor Greene (R-Ga.) has threatened to call a vote to take the speaker’s gavel away from Johnson, similar to what happened with his predecessor, former California representative Kevin McCarthy in October. She has cited Johnson’s stances on FISA, as well as whether to approve more aid to Ukraine in its fight against Russia, as deciding factors in whether she ultimately calls that vote.

Civil liberties groups wanted two big changes to FISA this time around: tweaks to prohibit law enforcement from buying personal data on Americans they would not be able to collect themselves without a warrant; and limits on searches that involve Americans.

House intelligence committee chair Mike Turner (R-Ohio) and the White House have defended the program, saying reforms have been made in the past and the further changes proposed by privacy advocates risked hurting the U.S.’ ability to keep track of terrorists.

“To protect the American people, we need to maintain this vital collection authority, while strengthening its protective guardrails with the most robust set of reforms ever included in legislation to reauthorize Section 702,” Jake Sullivan, the White House’s national security advisor, said Tuesday. “This bill does that.”

Opponents of the bill said they didn’t revolt Tuesday to embarrass Johnson but were instead angry over what they saw as his ham-handed attempts to avoid upsetting Turner or House Judiciary Chairman Jim Jordan (R-Ohio), whose committee put forward a deeply-revised FISA with far stronger protections for privacy.

After House Republicans regrouped late Wednesday to discuss the next step after the failed vote, Good said Johnson should allow more amendments to be voted on, though the White House has said some of the proposed amendments would dangerously hamper the government’s ability to keep tabs on surveillance targets.

“We ought to have amendments that are voted on, an open amendment process,” Good said.

Patrick Eddington, senior fellow with the libertarian Cato Institute, said in a blog post Wednesday that Johnson will now either have to go back and open up the amendment process or start trying to extend the current law with no changes, as was done in December.

“While either of those could still happen this week, the odds are better that a renewed FISA push in the House will happen early next week,” Edddington wrote.

The Senate could also send over a simple extension without changes, which could prompt Johnson to put it on the House floor under a requirement it get two-thirds of the votes in order to pass.

The GOP dissidents said another extension of the program would be preferable to the version of FISA blocked Wednesday. Those changes would have expanded FISA’s reach into some new areas, such as using surveillance to fight the fentanyl crisis.

But another possibility would be to just let the law lapse, which privacy advocates say would be no big blow to national security. A federal court that oversees the Section 702 program recently granted the government a certification recently that would allow at least some of those activities to continue until April 2025 in the event the law lapses.

In December, bumping up against a similar deadline, the Biden administration said the value of the program would be diminished if it lapsed because private-sector partners may rethink their cooperation.

“We are of the view that certifications remain valid (even if 702 lapses) but we know from experience that not all companies will accept that. Some of them will take the opportunity to no longer cooperate. This is not idle speculation,” said Josh Geltzer, deputy homeland security advisor.

Good, though, said he felt little pressure to act.

“I don’t think there’s any reason to rush by April 19,” Good said.