OpenJurist

25 USC 2803 - Law enforcement authority

The Secretary may charge employees of the Bureau with law enforcement responsibilities and may authorize those employees to
(1) carry firearms;
(2) execute or serve warrants, summonses, or other orders relating to a crime committed in Indian country and issued under the laws of
(A) the United States (including those issued by a Court of Indian Offenses under regulations prescribed by the Secretary), or
(B) an Indian tribe if authorized by the Indian tribe;
(3) make an arrest without a warrant for an offense committed in Indian country if
(A) the offense is committed in the presence of the employee,
(B) the offense is a felony and the employee has reasonable grounds to believe that the person to be arrested has committed, or is committing, the felony, or
(C) the offense is a misdemeanor crime of domestic violence, dating violence, stalking, or violation of a protection order and has, as an element, the use or attempted use of physical force, or the threatened use of a deadly weapon, committed by a current or former spouse, parent, or guardian of the victim, by a person with whom the victim shares a child in common, by a person who is cohabitating with or has cohabited with the victim as a spouse, parent, or guardian, or by a person similarly situated to a spouse, parent or guardian of the victim, and the employee has reasonable grounds to believe that the person to be arrested has committed, or is committing the crime;
(4) offer and pay a reward for services or information, or purchase evidence, assisting in the detection or investigation of the commission of an offense committed in Indian country or in the arrest of an offender against the United States;
(5) make inquiries of any person, and administer to, or take from, any person an oath, affirmation, or affidavit, concerning any matter relevant to the enforcement or carrying out in Indian country of a law of either the United States or an Indian tribe that has authorized the employee to enforce or carry out tribal laws;
(6) wear a prescribed uniform and badge or carry prescribed credentials;
(7) perform any other law enforcement related duty; and
(8) when requested, assist (with or without reimbursement) any Federal, tribal, State, or local law enforcement agency in the enforcement or carrying out of the laws or regulations the agency enforces or administers.