Interests don't necessarily give rise to rights, and the terms are not synonomous in law. There is also a difference between a party actually having a particular right or interest, or merely asserting that they do so.
The decision to dissociate oneself from a native tribe is a matter of behavior, not of status, therefore it is supremely illogical to use it as a basis to determine one's legal status as a human being.
I'm thinking along the lines, that regardless of tribal membership, it does not fundamentally alter their nature as persons.
The framework created in Roe is limited to the single purpose of determining whether there are separate competing rights such that the state can assert a protective interest independent of the woman carrying the fetus.
It seems to me that while the framework elucidates an interest of the state in the unborn child, they cite an arbitrary definition to define whether the interests are compelling.
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