The armed forces can’t execute law domestically. The question driving the discussion here is what exactly constitutes “executing law.” According to DoD policy, the armed forces are prohibited from performing the following law enforcement activities:

• interdiction of a vehicle, vessel, aircraft, or other similar activity

• a search or seizure;

• an arrest; apprehension; stop and frisk; engaging in interviews, interrogations, canvassing, or questioning of potential witnesses or suspects; or similar activity;

• using force or physical violence, brandishing a weapon, discharging or using a weapon, or threatening to discharge or use a weapon except in self-defense, in defense of other DoD persons in the vicinity, or in defense of non-DoD persons, including civilian law enforcement personnel, in the vicinity when directly related to an assigned activity or mission;

• evidence collection; security functions; crowd and traffic control; and operating, manning, or staffing checkpoints;

• surveillance or pursuit of individuals, vehicles, items, transactions, or physical locations, or acting as undercover agents, informants, investigators, or interrogators; and

• forensic investigations or other testing of evidence obtained from a suspect for use in a civilian law enforcement investigation

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