"Sovereign citizen groups are loose associations of antigovernment extremists who do not recognize the Federal Government. They believe they are separate or sovereign from the United States and are exempt from Federal, State, and local laws and tax systems. They believe the county sheriff is the supreme law enforcement officer in the land and county clerks or registrars are the only legitimate elected officials. They subscribe to a belief in 'common law' and their right to arrest or sue employees of the 'illegitimate government.' They are known for filing nuisance lawsuits or liens against individuals who try to stop their schemes, which have involved in lender, credit card, tax, and loan frauds. They make their own driver's licenses and license plates and sometimes attempt to form their own parallel institutions of government. Sovereign citizen encounters with law enforcement and government personnel frequently become confrontational and sometimes turn violent. The most extreme example of sovereign citizen violence was exhibited by Terry Nichols, coconspirator in the Alfred P. Murrah Federal Office Building bombing in 1995. The 2014 standoff between the Federal Government and a cattle rancher in Nevada also involved sovereign citizens and even more radical militia groups. The Federal Bureau of Investigation (FBI) and HUD OIG [U.S. Department of Housing and Urban Development Office of the Inspector General] have noticed a resurgence of sovereign citizen fraud in HUD program."
U.S. Department of Housing and Urban Development, Office of the Inspector General: https://www.hudoig.gov/