25 U.S.C. § 2803 — Law enforcement authority

The Secretary^* may assign Bureau^* employees law-enforcement responsibilities and authorize them to: (1) carry firearms; (2) execute or serve warrants, summonses, and other crime-related orders issued under United States law, including Court of Indian Offenses orders under the Secretary’s regulations and Central Violations Bureau matters, or issued under an Indian tribe’s law if the tribe authorizes it; (3) arrest without a warrant for an offense^* in Indian country^* when (A) it occurs in the employee’s presence; (B) it is a felony and the employee has probable cause to believe the person committed or is committing it; (C) it is a misdemeanor domestic-violence, dating-violence, stalking, or protection-order crime involving use or attempted use of physical force or threatened use of a deadly weapon, committed by a current or former spouse, parent, guardian, someone sharing a child with the victim, a current or former cohabiting spouse, parent, or guardian, or someone similarly situated, and the employee has probable cause; or (D) it involves (i) a misdemeanor controlled-substance offense under the Controlled Substances Act, title IX of the Personal Responsibility and Work Opportunity Reconciliation Act of 1996, or section 865 of title 21; a misdemeanor firearms offense under chapter 44 of title 18; a misdemeanor assault under chapter 7 of title 18; or a misdemeanor liquor-trafficking offense under chapter 59 of title 18, and (ii) the employee has probable cause; (4) offer and pay rewards for services or information, or buy evidence, that helps detect or investigate an Indian-country offense or arrest an offender against the United States; (5) question any person and give or take an oath, affirmation, or affidavit about a matter relevant to enforcing United States law or authorized tribal law in Indian country; (6) wear a required uniform and badge or carry required credentials; (7) perform other law-enforcement duties; and (8) when asked, assist, with or without reimbursement, Federal, tribal, State, or local law-enforcement agencies in enforcing or carrying out the laws or regulations they administer.