Tribal officers can be sued in federal court regarding black Cherokee's rights to continuing tribal membership under 1866 treaty. In 2008, the DC appellate court had stated that the tribe had treated away its right to discriminate against the freedmen.
From the judges decision in the Cherokee Freedmen case:
As a practical matter, therefore, the Cherokee Nation and the Principal Chief in his official capacity are one and the same in an Ex parte Young suit for declaratory and injunctive
relief. As a result, the Principal Chief can adequately represent the Cherokee Nation in this suit, meaning that the Cherokee Nation itself is not a required party for purposes of
By contrast, if we accepted the Cherokee Nation’s position, official-action suits against government officials
would have to be routinely dismissed, at least absent some statutory exception to Rule 19, because the government entity in question would be a required party yet would be immune from suit and so could not be joined. But that is not how the Ex parte Young doctrine and Rule 19 case law has developed.
In light of our disposition, we need not reach the Freedmen’s argument that the Cherokee Nation waived its
sovereign immunity by filing a related suit in Oklahoma. We reverse the judgment of the District Court and remand for further proceedings consistent with this opinion.