Here:

Here are the materials in Graham v. Muscogee (Creek) Nation Citizenship Committee (also here):
Doc.-4-Appellants-Brief-02242020
Doc.-14-Appellees-Response-Brief-06122020
From High Country News, here.
Here are the materials in New Holy v. Dept. of the Interior (D.S.D.):
Fletcher’s paper, “Indian Lives Matter — Pandemics and Inherent Tribal Powers,” is now available online (PDF).
Yesterday, we covered tribal constitutions. Today, the political and bureaucratic complexity of enrollment decisions in cartoon form (we will conclude tomorrow):
Apparently, in 1977 or so, the Phoenix Area Office decided to write a lengthy manual for tribal governments, instructing them on how to make enrollment decisions that met tribal constitutional muster. Suffice it to say the text is TL:DR, but the illustrations are awesome — and by awesome, I mean crazy — and by crazy, I mean Indian country crazy.
Tomorrow, how tribal governments make membership decisions….
Here are the materials in Hudson v. Zinke (D.D.C.):