Here is the opinion in United States v. Langford (us-v-langford-dct-opinion), and its companion case, United States v. McHone (us-v-mchone-dct-opinion), out of the Western District of Oklahoma. The claimant, a non-Indian prosecuted under the Indian Country Crimes Act and the Assimilative Crimes Act, unsuccessfully argued that the federal court had no criminal jurisdiction over him (the underlying crime was cock-fighting, illegal under Oklahoma law).

However, the court also held that the magistrate judge erred in sentencing the defendant to a fine larger than that allowable under Oklahoma law.

Finally, the court dropped an interesting footnote in the Langford opinion:

In his brief, defendant asserts that pursuant to the Indian Civil Rights Act, he is entitled to all rights afforded to tribal members. The Indian Civil Rights Act, however, undertakes to single out the more important civil rights contained in the United States Constitution and to make those applicable to tribal members. See Martinez v. Santa Clara Pueblo, 540 F.2d 1039, 1042 (10th Cir.1976). Because defendant is not a tribal member, the Court finds the Indian Civil Rights Act is inapplicable in this case.

The citation is to the Martinez panel opinion, not the Supreme Court opinion. I wonder if other circuits have found the same.