Here is the opinion in United States v. Jacobs: United States v. Jacobs CA8 Opinion.
The court’s syllabus:
Argument that the government’s failure to comply with the provisions of the Fort Laramie Treaty deprived the district court of criminal jurisdiction rejected; even if Articles I and V of the treaty could reasonably be construed as establishing a jurisdictional requirement at the time the Treaty was executed, Congress’s subsequent grant of citizenship to the Indians makes them subject to all restrictions to which any citizen is subject and is evidence of a clear indication to abrogate any contrary treaty provisions.
And the briefs are here.
Turtle Talk 
The l868 Treaty with the Lakota Nation negotiated U.S. Citizenship based on
relationship to the land but it also acknowledged dual citizenship; that of
being Lakota. Lakota possess dual citizenship. The legislation in l87l by the
Congress of the United States to abrogate the act of making treaties states
clearly, that the provisions of the treaty remain continuing rights under the
treaty. The Major Crimes Act is one of three human rights violations perpetu-
ated against the lakota. The U.S. Court in Cedar Rapids, Iowa validated the
l868 Treaty in the l970’s. This Eighth Circuit Decision must be appealed.