Customs and Border Protection Border Patrol Agent (CBP BPA) Exam 2025 – 400 Free Practice Questions to Pass the Exam

The document that establishes 50% American Indian blood is tribal certification. This certification is issued by a federally recognized tribe and serves as an official confirmation of an individual's tribal enrollment, which specifically includes details about the percentage of American Indian ancestry.

Blood quantum, or the degree to which a person can claim Native American ancestry, is a critical factor in determining eligibility for tribal membership and the benefits that may accrue from that membership. Tribal certifications take into account the individual's lineage and the tribal eligibility requirements, which often stipulate a specific blood quantum percentage required for enrollment.

Other documents mentioned, such as a child's passport, Form I-181 (which is an application for lawful permanent resident status), and Temporary I-551 (a type of evidence of permanent residence), do not pertain to establishing the degree of American Indian blood and are typically used for immigration or identification purposes. These documents do not provide the lineage verification that tribal certification does, making it the valid choice for establishing 50% American Indian blood.