http://usmilitary.about.com/od/justicelawlegislation/a/gangs.htmThe report, Gang Activity in the U.S. Armed Forces Increasing, dated January 12, states that members of nearly every major street gang have been identified on both domestic and international military installations. Members of nearly every major street gang, including the Bloods, Crips, Black Disciples, Gangster Disciples, Hells Angels, Latin Kings, The 18th Street Gang, Mara Salvatrucha (MS-13), Mexican Mafia, Nortenos, Surenos, Vice Lords, and various white supremacist groups, have been documented on military installations. Although most prevalent in the Army, the Army Reserves, and the National Guard, gang activity is pervasive throughout all branches of the military and across most ranks, but is most common among the junior enlisted ranks, according to the report. The extent of gang presence in the armed services is often difficult to determine since many enlisted gang members conceal their gang affiliation and military authorities may not recognize gang affiliation or may be inclined not to report such incidences.
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Even though the policy violates Military recruiting regulations, US criminal courts have allowed gang members to enter the service as an alternative to incarceration. Several instances wherein gang members have been recruited into the armed services while facing criminal charges or on probation or parole have been documented. In many instances, a gang member facing criminal charges may be provided the option to join the military or serve a jail sentence. Furthermore, some army recruiters have been known to conceal recruits' gang affiliation to help boost their enlistment numbers.
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Gang membership in the armed forces can disrupt good order and discipline, increase criminal activity on and off military installations, and compromise installation security and force protection. Gang incidents involving active-duty personnel on or near US military bases nationwide include drive-by shootings, assaults, robberies, drug distribution, weapons violations, domestic disturbances, vandalism, extortion, and money laundering. Gangs have also been known to use active-duty service members to distribute their drugs.
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Military-trained gang members also present an emerging threat to law enforcement officers patrolling the streets of US cities. Both current and former gang-affiliated soldiers transfer their acquired military training and knowledge back to the community and employ them against law enforcement officers, who are typically not trained to engage gangsters with military expertise. Gang members in the military are commonly assigned to military support units where they have access to weapons and explosives. Military personnel may steal items by improperly documenting supply orders or by falsifying paperwork. Law enforcement officials throughout the United States have recovered military-issued weapons and explosives-such as machine guns and grenades-from criminals and gang members while conducting search warrants and routine traffic stops.