"The United States participated only as amicus before the Eighth Circuit Court of Appeals in Cook v. Parkinson, 525 120 (8th Cir. 1975), a criminal case that discussed Bennett County as no longer being part of the Reservation. The United States is not bound by that decision because it did not participate in the litigation. The United States was part in United States v. Bennett County, 394 8 (8th Cir. 1968), in which the State of South Dakota had to obtain permission from the Department of Interior in order to fix roads or condemn property Bennett County, consistent with the property's Reservation status."