The U.S. Senate is poised to vote on a bill that would expand the FBI's secret surveillance powers, including warrantless collection of browsing history, Reuters reports.
Lawmakers will vote on the amendment, sponsored by Sens. John McCain (R-Ariz.) and John Cornyn (R-Texas), no later than Wednesday.
If approved, the bill would expand the FBI's authority to use the so-called National Security Letters (NSL) to obtain Electronic Communication Transaction Records (ECTR) such as email time stamps, senders, and recipients, as well as browsing metadata such as history and location—all without a warrant.
The amendment, which McConnell attached to a criminal justice appropriations bill, has received widespread criticism from civil liberties groups.
Digital rights organization Electronic Frontier Foundation (EFF) previously referred to the NSLs as "one of the most frightening and invasive" government surveillance powers that were expanded under the U.S. Patriot Act, and noted that the FBI is guilty of "systemic abuse of this power."
NSL recipients are also subject to a gag order that prohibits them from ever revealing the existence of the letters to anyone, from their coworkers to the public at large.
Fight for the Future launched a campaign calling on senators to vote it down, stating, "The information the FBI wants is too sensitive to remove oversight."
Opponents in the chamber agree. Sen. Ron Wyden (D-Ore.), an outspoken critic of mass surveillance, said of a similar measure last month that it "takes a hatchet to important protections for Americans' liberty."
Republicans invoked the mass shooting in Orlando earlier this month as justification for the new amendment. McCain said in a statement, "In the wake of the tragic massacre in Orlando, it is important our law enforcement have the tools they need to conduct counterterrorism investigations."
However, as opponents noted, the amendment would have been unlikely to stop the attack. As national security expert Marcy Wheeler pointed out in a blog post on Tuesday, FBI director James Comey previously said that the agency had already obtained shooter Omar Mateen's ECTR. "So it is false to say this is a real response," she wrote.
Senate Majority Leader Mitch McConnell reportedly made the move late Monday—the same day that the Senate rejected four gun control measures also introduced as a response to the shooting.
Last week, the U.S. House of Representatives failed to pass a bipartisan amendment that would have limited government surveillance powers by prohibiting warrantless collection of Americans' electronic communications and banning the government from forcing technology companies to install backdoors to encrypted devices.
One of that bill's sponsors, Rep. Thomas Massie (R-Ky.), said the House amendment "doesn't take any tools away from those that want to investigate what happened in Orlando, none whatsoever."
"I think our citizens are fed up with being spied on by the government," Massie said.