The law that gives the National Security Agency the legal authority to spy on millions of Americans is set to expire at the end of the year.

That might sound like good news, a chance to perhaps scale back the agency's far-reaching powers and rethink how far its tentacles are allowed to reach into the lives of private citizens across the US.

Not so much. In fact, Congress is rushing through a bill that will expand the NSA's legal authority to collect, analyze, and act on the digital communications of American citizens.

Rep. Devin Nunes is pushing the innocuous-sounding "FISA Amendments Reauthorization Act of 2017," based on another bill submitted by Sen. Richard Burr. The bill looks to maintain and potentially expand the NSA's powers for the next seven years.

It's troubling, and a vote is expected to be rushed through this week.

The main issue with the new bill up for vote, which intelligence officials say is vital for preventing terror attacks, is its provisions for "about" collection, which allows the NSA to look through communications that merely mention a target, not those that were sent or received by that target.

The NSA rolled back this provision in April this year, but the bill would cement this kind of surveillance as being well within the agency's legal authority. The agency could restart "about" collection after giving Congress 30 days notice, The Hill reports.

The bill also aims to codify a controversial provision in the law that allows the NSA to collect texts, emails, and social media content of Americans who have been communicating with foreigners abroad — at to do so without a warrant. It's a dicey loophole that plays fast and loose with the Constitution's Fourth Amendment protections.

Oh, and just like the healthcare bill, this one has been "jammed through" without enough time for members to read the thing and debate the implications, Daniel Schuman, policy director for grassroots organization Demand Progress, says.

If passed, the legislation would renew the program until 2025. The Trump administration initially hoped to have it renewed in perpetuity.

"Unconstitutional surveillance"

Privacy and human rights groups alike have slammed the bill. The Electronic Frontier Foundation (EFF) warned that if it passed, "nothing will be done to rein in the massive, unconstitutional surveillance of the NSA on Americans or innocent technology users worldwide."

The group has set up a tool to allow you to easily tweet at your member of Congress. All it takes is a zip code.

We're calling on members of the House of Representatives to oppose the NSA expansion bill being brought for a vote tomorrow. Defend the Constitution. Oppose H.R. 4478. https://t.co/UPch8qdFB7 — EFF (@EFF) December 20, 2017

The ACLU also voiced strong opposition, cautioning that human rights defenders, journalists and whistleblowers are all at risk of being caught up. It's calling on the public to call Congress to demand the legislation be blocked.

“The last decade has demonstrated time and again that when surveillance laws are negotiated in secret and rushed through Congress with little debate, it often leads to abuse and constitutional violations," the organization's legislative counsel Neema Singh Guliani said.

"Yet House leadership appears poised to repeat past mistakes and quickly push for a vote on this hastily drafted legislation without giving members of Congress or the public time to debate the important privacy interests at stake.”

This is what Section 702 in its current form allows the government to do. These surveillance powers must be brought in line with the Constitution, not expanded — but that's what House leaders are now trying to do. pic.twitter.com/SloI8y7CqC — ACLU (@ACLU) December 20, 2017

Edward Snowden joined ACLU's Neema Singh Guliani and Ashley Gorski, the organization's attorney with the National Security Project, for a Reddit AMA Wednesday to discuss the bill and its implications. They were flooded with questions.

"What do y'all think is the most disturbing thing the NSA has the capability of doing in regards to surveillance?" one poster asked.

Snowden said that the scariest thing is "that the NSA can 'ingest' into its surveillance systems without a warrant any communication that is only 'one end domestic.' Does that sound right to you?"

"That's the power they're trying to expand right now," he said, "and they'll succeed at it unless they get flooded with calls before the vote."