The Cherokee Nation voted to eject descendents of slaves owned by Cherokees from membership in their nation. By a 3/4ths vote, only "blood" members of the tribe can be part of the nation.
Counting membership in Indian "nations" is one of the last remaining acts of blood racism recognized by U.S. law. They are the last remnant of the 19th century pseudo-science of race which worked so much havoc in every other area of American life. There are many irrationalities in the treatment of native American tribes in our law. I think it is time to put this one to rest.