Here is United States v. Cavanaugh (D. N.D.), where the court dismissed an indictment under the federal domestic violence by a habitual offender in Indian Country statute (18 U.S.C. 117), holding that the use of prior uncounseled tribal court D.V. convictions to establish the “habitual” element of the crime was unconstitutional. See my paper on how state courts should use, if at all, uncounseled tribal court convictions. The court rejected claims that the statute itself was unconstitutional under Morrison and Lopez.
Here are the materials: