The United States faces a domestic threat that is largely ignored by counterterrorism practitioners and policy: the Sovereign Citizens Movement. The adherents of this antigovernment movement have committed violent, even terroristic, acts and employed paper terrorism tactics. The group clogs courts and harasses government officials, but a paucity of hard data on the Sovereigns has stymied any concerted or unified response. Law enforcement officials have yet to determine how many Sovereigns are active in the United States, where they are concentrated, or whether the movement is gaining adherents. This thesis addresses the dearth of information on the Sovereign Citizens Movement. It relies on both quantitative and qualitative research, providing a detailed analysis of 548 court cases. The assessment of the groups targets, related court vulnerabilities, and relevant statewide statistics can be harnessed into quality policy decisions. This work proves the increasing trend in Sovereign Citizen activities, exposes the gaps in the present literature and domestic terrorism policy, and provides recommendations for prescriptive policy changes across the spectrum of agencies responsible for countering domestic terrorist threats.