From AR 190-56 .
5-1. General .
This chapter prescribes the authority of DACP/SGs performing law enforcement or security functions on Army installation/activities..
5-2. Au…thority .
a. DACP/SGs performing law enforcement and security duties authorized by the installation/activity commander may apprehend any persons found on the installation/activity for offenses committed on post that are felonies, misdemeanors, breaches of the peace, a threat to property or welfare, or detrimental to good order and discipline. Such apprehension authority is limited to issuing citations and turning the subject over to the appropriate civilian or military authorities..
b. DACP/SG personnel while on duty are considered part of the Department of the Army and, therefore, are subject to the restrictions on aid to civilian law enforcement imposed by section 1385, title 18, United States Code (18 USC 1385), commonly known as the Posse Comitatus Act. Accordingly, any proposed aid to civilian law enforcement must be reviewed by the servicing SJA..
c. Army security guard authority and jurisdiction to perform force protection tasks on their installation/activity are valid while performing these duties during their work hours only. An on-post apprehension conducted by an Army security guard in an off-duty status is a detention by a private citizen. Army security guards will not carry Army weapons while off-duty. Army weapons are not permitted for carrying on a stand-by basis. Army security guards while on duty will not carry privately-owned weapons or privately-owned ammunition. The carrying of privately-owned weapons on post, by off-duty DACP/SGs, will be in accordance with policy established by the installation/activity commander..
d. Army civilian police authority and jurisdiction to perform law enforcement tasks are valid while performing these duties during their work hours only. An on-post apprehension conducted by Army civilian police in an off-duty status is a detention by a private citizen. Army civilian police will not carry Army weapons while off duty. Army weapons are not permitted for carrying on a stand-by basis. Army civilian police while on duty will not carry privately-owned weapons or privately-owned ammunition. The carrying of privately-owned weapons on post by off-duty Army civilian police will be in accordance with policy established by the installation/activity commander..
e. Contract security guards will not carry Army weapons while off duty. Contract security guards while on duty will not carry privately-owned weapons or privately-owned ammunition. The carrying of privately-owned weapons on post by off-duty CSGs will be in accordance with policy established by the installation/activity commander..
f. DACP are authorized and will be issued standardized credentials/identification cards DA Form 7599 (Department of the Army Police Officer Credential) (see fig 5-1). The duty uniform and badge may only be worn while on duty or while traveling to and from work as determined by PM/designated command security/law enforcement representative. While wearing the duty uniform and badge, civilian police officers may intervene to perform law enforcement tasks on their installation/activity. The credentials/identification card will have the limits of authority clearly showing the authority is only valid while on the military installation, and the credentials/identification card will not be kept in the same holder as the badge..
g. The authority and liability of civilian security guards overseas depends on applicable international agreements, Status of Forces Agreement, and local law. Seek the advice of OCONUS SJA regarding the status of such personnel..
5-3. Written instructions .
a. The installation/activity commander, in conjunction with the SJA and PM/designated command security/law enforcement representative, will document their specific delegation of authority for DACP/SGs within their respective jurisdiction (see app F). Collective delegations by functional groupings (that is, police officers, Job Series 0083; security guards, Job Series 0085) or by position title (for example, desk officer, lead police officer, police officer, guard, lead guard, and so forth) may be made. In addition, procedures must be established to ensure each DACP/SG acknowledges in writing, a clear understanding of their authority and jurisdiction. Written instructions will be reviewed at least once a year and updated, if necessary..
b. Because of potential conflicts of interest and Posse Comitatus Act issues, DACP/SGs while wearing the duty uniform and/or badge, may not be deputized or exercise any additional authority and jurisdiction other than given by the installation/activity commander as specified in paragraph 5-3a, above, while on duty. ( Full Answer )