The FBI is in hot water for misusing a powerful surveillance tool nearly 300,000 times in 2020 and early 2021, including to search for information about Americans linked to the Jan. 6, 2021, attack on the U.S. Capitol or arrested during Black Lives Matter protests.

The tool in question is a vast database known to the intelligence community as Section 702. Here's what to know about it and what the FBI did with it.

The Section 702 database is one of the most powerful collection tools the intelligence community has.

It's a massive communications database — containing emails, texts and phone calls — that the government uses to prevent terrorist attacks and gather information about foreign governments' intelligence activities.

The database was developed in the wake of the Sept. 11, 2001, terrorist attacks, and the intelligence community has for years said it's one of its most potent tools. It's named after the section of the Foreign Intelligence Surveillance Act that created it, Section 702. The system "plays an outsized role in protecting the nation, providing some of the U.S. government's most valuable intelligence on our most challenging targets," the director of the National Security Agency, Paul M. Nakasone, recently said.

But while the database directly targets foreigners not in the United States, it also sweeps up communications of U.S. residents and business entities that have communicated with those foreigners. And because so much internet data is transnational, stored in computer servers around the world, it is unclear how much of the database consists of communications involving Americans.

"Say I want to collect information on Vladimir Putin," explained Barbara McQuade, a former U.S. attorney, "and I see on his Gmail, it turns out he's been talking to an American. So I'm collecting on Putin, but it might capture communications with a U.S. person, and so now in that database, I have every email he's ever sent, and I can go in and query for that U.S. person."

The FBI is supposed to search the 702 database for information about U.S. residents or companies only when the FBI agent or analyst has a reason to believe such a query may generate foreign intelligence information or evidence of a crime. The FBI is supposed to follow strict procedures because using the database allows the bureau to skip the usual step of getting a warrant from a federal court to collect information on Americans.

The FBI has been misusing Section 702 to conduct hundreds of thousands of searches on a wide variety of Americans

In 2020 and early 2021, the FBI misused the database more than 278,000 times by conducting searches that didn't follow Justice Department rules, often to look for information on Americans who don't have connections to national security, The Washington Post's Devlin Barrett reports. The FBI has searched the database for "crime victims, Jan. 6 riot suspects, people arrested at protests after the police killing of George Floyd in 2020 and - in one case - 19,000 donors to a congressional candidate, according to a newly unsealed court document," he reports.

The FBI acknowledges these widespread misuses of the database and said it fixed the problem recently by making clear to its agents and analysts what they can and can't search for, and by requiring an FBI agent to put in writing why they are querying the system.

The chronic misuse came to light during Justice Department audits, leading to a secret federal court review of how the FBI uses the program. The court's findings were revealed Friday.

The case against Section 702

Civil liberties advocates say the FBI uses Section 702 as a backdoor for warrantless searches to get around the courts. "It's a go-to domestic spying tool for the FBI," writes Elizabeth Goitein of the Brennan Center for Justice.

This is not the only time the FBI has been in trouble for the database. Another recent audit found multiple problems, including that the FBI used the database to search for the name of a member of Congress. One think tank regularly tracks known intelligence community abuses of Section 702 over the past 15 years.

The database has long been subject to lawsuits from the American Civil Liberties Union, which has tried to get courts to declare it unconstitutional under the 4th Amendment, which prohibits unreasonable search and seizure of Americans. But the Supreme Court has upheld Section 702, and Congress has continued to approve it.

What could happen next

The FBI has been in the crosshairs of Republicans pretty much since Donald Trump became president. The agency played a key role in investigating the 2016 Trump campaign's connections to Russia, and FBI agents wiretapped a Trump campaign adviser, Carter Page. But officials later acknowledged that the FBI used incomplete and misleading claims to get a court to approve the wiretap. (A recent report from special counsel John Durham criticized how the FBI went about the Trump-Russia investigation.)

Republicans in Congress recently propped up a subcommittee dedicated to trying to find abuses within the FBI and other federal agencies. It's likely they'll investigate how the FBI uses this database. (Though the evidence suggests the FBI was searching for Black Lives Matter protesters as much as Jan. 6 suspects.) The federal court that reviewed how the FBI uses the database threatened to put major limitations on the agency's ability to use it if the FBI did not change its procedures.

Congress is soon voting on whether to continue Section 702, which will expire by the end of this year without congressional approval. It could be an uphill fight for the intelligence community to persuade lawmakers to approve the database as is.

"You can tell your department," Sen. Mike Lee (R-Utah) told Attorney General Merrick Garland recently, "not a chance in hell we're going to be reauthorizing that thing without some major, major reforms."