25 CFR § 81.57 - How do I determine how many signatures are needed for a petition to be valid?
(2) The Local Bureau Official will:
(i) Contact the tribal governing body to obtain the current number of tribal members, 18 years of age or older, to determine the number of tribal members who must sign a petition as required by the tribe's governing document; and
(ii) Notify the petitioners' spokesperson how many signatures are required and that the number is valid for 180 days from the date of this notification.
(b) For a federally recognized tribe adopting a governing document under Federal statute for the first time, the petition must have signatures of 50 percent of the tribal members who are 18 years of age or older.
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