The case is United States v. Nahwahquaw, out of the Eastern District of Wisconsin — NAHWAHQUAW Report and Recommendation (the district court judge adopted the recommendation). An excerpt:

Even if the court were to conclude that the defendant can maintain a facial challenge to § 1153(a), which it does not, the term “Indian” is not unconstitutionally vague on its face. Although “Indian” is not defined in the statute, the test for determining “Indian” status has been judicially defined over the years and is well established under federal law. The test, first suggested in United States v. Rogers, 45 U.S. 567 (1846) and generally followed by the courts, considers: “(1) the degree of Indian blood; and (2) tribal or governmental recognition as an Indian.” United States v. Torres, 733 F.2d 449, 456 (7th Cir.1984) (quoting United States v. Broncheau, 597 F.2d 1260, 1263 [9th Cir.1979] ) (emphasis supplied by Torres ); See also, United States v. Keys, 103 F.3d 758, 760 (9th Cir.1996); United States v. Dodge, 538 F.2d 770, 786 (8th Cir.1976). Tribal enrollment is “the common evidentiary means of establishing Indian status, but it is not the only means nor is it necessarily determinative.” United States v. Bruce, 394 F.3d 1215, 1224 (9th Cir.2005) (quoting Broncheau, 597 F.2d at 1263); accord, United States v. Antelope, 430 U.S. 641, 646 n. 7 (1977).