There are a number of active gangs operating among the inmates in prisons. "The environment in most U.S. prisons is ripe for recruiting and controlling gang members because inmates tend to form associations for self-protection along racial, ethnic, and cultural lines," according to the National Gang Threat Assessment (National Alliance of Gang Investigators Associations, February 2000, http://www.nagia.org/table_of_contents.htm). In addition to providing mutual protection, prison gangs are also involved in selling drugs and other contraband. They routinely use violence and intimidation to dominate other inmates.

The BJS defines gangs as groups that commit illegal acts and have five or six of the following characteristics:

• Formal membership with a required initiation or rules for members
• A recognized leader or certain members whom others follow
• Common clothing or group colors, symbols, tattoos, or special language
• A group name
• Members from the same neighborhood, street, or school
• Turf or territory where the group is known and where group activities take place

The Florida Department of Corrections (http://www.dc.state.fl.us/pub/gangs/prison.html) identified six major gangs operating in prisons in early 2005. They are: Neta (Puerto Rican inmates), the Aryan brotherhood (white inmates), the Black Guerrilla Family (African-American male inmates), the Mexican Mafia, La Nuestra Familia, and the Texas Syndicate (all Mexican-American inmates). While these gangs operate in prisons nationwide, such street gangs as the Crips, Bloods, Latin Kings, Barrio Aztecas, Black Gangster Disciples, and Nazi Low Riders are known to be operating in prisons as well.