Despite the fact that Section 702 explicitly prohibits the targeting of USA citizens and residents, the government has routinely engaged in these "backdoor searches". But fewer lawmakers there appear to favour major changes to spying laws, so the House vote is likely the effective end of a debate over 21st-century surveillance technology and privacy rights that broke out in 2013 following the leaks by the intelligence contractor Edward J. Snowden.
So what's wrong with that? Sometimes, though, their data are collected anyway - as a result of communicating with foreigners who are overseas, for example.
Senior government officials can ask spy agencies to unmask the names of Americans or U.S. organisations if they believe that will help them better understand the underlying intelligence.
Supporters of the Nunes-Schiff bill also argued that requiring the Federal Bureau of Investigation to obtain a warrant may impede fast-moving terror plots. The Fourth Amendment states that individuals can not be subjected to "unreasonable searches and seizures" without a warrant, obtained "upon probable cause" that a crime is being committed. "Spying is valid to find the foreign agents among us, but it's gotta be based on suspicion". But Americans' communications - even those in the USA - can be snared if they are part of conversations that the targets are having.
There's no way to know for sure unless you are charged with a crime and prosecutors disclose that they have evidence obtained through Section 702.
What did Congress do Thursday?
The bill would extend Section 702 of the Foreign Intelligence Surveillance Act until December 31, 2023.
Instead, the greater threat to the fate of Section 702 came from the president himself, in a series of contradictory and seemingly misinformed tweets he fired off after watching a segment about the bill on the Fox News Channel.
The House defeated an alternative bill by Reps. Whatever your view on the decades-old law, it's clear the president has little understanding of it, proven by the fact he did a complete turnabout in under two hours when he ranted about it on Twitter.
Napolitano convinced Trump to oppose the bill, and Trump tweeted accordingly.
As the tweet buzzed in notifications from Capitol Hill to the Central Intelligence Agency headquarters in Langley, Virginia, Trump's advisers hurried to draft a follow-up that might help preserve the administration's position in support of the act's reauthorization.
But what exactly is FISA, and what is Congress set to decide about the law?
The 256-154 vote to renew the Foreign Intelligence Surveillance Act capped a wild day of debate that started when President Donald Trump tweeted misleadingly that the National Security Agency's program "may have been used.to so badly surveil and abuse the Trump Campaign by the previous administration and others".
Trump later tweeted what seemed to be a clarification of his position in favor of renewing the law, saying that "today's vote is about foreign surveillance of foreign bad guys on foreign land". Trump later sent another tweet telling lawmakers to "get smart" and vote for the FISA bill.
Although controversial, officials from Democratic and Republican administrations have argued the eavesdropping tool is vital to counterterrorism and counterespionage efforts and has saved lives - an argument echoed by Trump's own White House. It now goes to the Senate. Republican Senator Rand Paul and Democratic Senator Ron Wyden immediately vowed to filibuster the measure but it was unclear whether they could convince enough colleagues to force changes.