Oath Keepers is an American far-right anti-government militia organization composed of current and former military, police, and first responders who pledge to fulfill the oath that all military and police take in order to "defend the Constitution against all enemies, foreign and domestic". It encourages its members to disobey orders which they believe would violate the U.S. Constitution. The organization claims a membership of 35,000 as of 2016, though the Anti-Defamation League (ADL) has estimated its membership at several thousand. Researchers estimate the number as probably no higher than 5,000.Several organizations that monitor U.S. domestic terrorism and hate groups describe the group as extremist or radical. The FBI describes the Oath Keepers as a “paramilitary organization” and a “large but loosely organized collection of militia who believe that the federal government has been coopted by a shadowy conspiracy that is trying to strip American citizens of their rights.” Mark Pitcavage of the ADL describes the group as "heavily armed extremists with a conspiratorial and anti-government mindset looking for potential showdowns with the government." The Southern Poverty Law Center (SPLC) lists the group's founder Elmer Stewart Rhodes as a known extremist and describes his announced plans to create localized militia units as "frightening". According to the SPLC, the group espouses a number of conspiracy and legal theories associated with the sovereign citizen movement and the white supremacist posse comitatus movement. SPLC senior fellow Mark Potok describes the group as a whole as "really just an anti-government group who believe in a wild set of conspiracy theories".Oath Keepers were present wearing military fatigues in Ferguson, Missouri, during the 2014 and 2015 unrest in the city, when members armed with semi-automatic rifles roamed streets and rooftops. Members of the group were indicted on conspiracy charges for allegedly staging a planned mission during the 2021 storming of the United States Capitol.