The Terrorist Watchlist and No Fly List

Before 9/11, agencies kept a dozen separate watchlists. In September 2003 a presidential directive created the Terrorist Screening Center, run by the FBI with other agencies, to maintain one consolidated list, now called the Terrorist Screening Dataset. Agencies nominate people based on reasonable suspicion that they are known or suspected terrorists, and the list includes more than a million identities, most of them foreigners outside the United States.

The list is shared with border officers, consular officers who decide visas, the Transportation Security Administration, police who run checks during traffic stops, and allied governments. Subsets include the No Fly List, which bars people from flying in or over the United States, and the Selectee List, which requires extra screening. People who believe they were wrongly listed can file complaints through the Homeland Security redress program, though the government generally will not confirm or deny whether someone is listed.

Courts have required more process for Americans on the No Fly List, and since 2015 U.S. citizens denied boarding may learn their status and challenge it. In FBI v. Fikre in 2024 the Supreme Court unanimously ruled that removing a person from the list does not automatically end their lawsuit. Civil liberties groups say the reasonable suspicion standard is too low and that the list has swept in innocent people, disproportionately Muslims, while officials say it is a vital tool that has stopped dangerous people from boarding planes and entering the country.