(June 29, 2018, 1:48 PM EDT) -- WASHINGTON, D.C. — U.S. Supreme Court guidance is needed to cure the “disparate treatment” accorded by the United States to black slaves of Indians who were freed after the Civil War in relation to the treatment of members of the tribes that once kept blacks as slaves, a descendant of one of the freedmen and an organization that advocates for freedmen rights tell the high court in their June 14 petition for a writ of certiorari (Leatrice Tanner-Brown, et al. v. Ryan Zinke, et al., No. 17-1681, U.S. Sup., 2018 U.S. S. Ct. Briefs LEXIS 2320)....