A federal lawsuit was filed in U.S. District Court in Oklahoma City on behalf of Rhonda Grayson and Jeffrey Kennedy against Muscogee Nation Principal Chief David Hill and the Citizenship Board. The suit alleges violations of an 1866 treaty and seeks enforcement of Muscogee Nation Supreme Court rulings that recognized the plaintiffs as entitled to citizenship. The tribe's headquarters is in Okmulgee, Oklahoma, and the nation is one of five in the state that historically practiced slavery.