Gangs in the United States

Gangs in the United States include several types of groups, including national street gangs, local street gangs, prison gangs, motorcycle gangs, and ethnic and organized crime gangs. Approximately 1.4 million people were part of gangs as of 2011, and more than 33,000 gangs were active in the United States.

Many American gangs began, and still exist, in urban areas. In many cases, national street gangs originated in major cities such as Los Angeles, Chicago, Philadelphia, Miami and New York City, and they later migrated to other American cities such as Atlanta, Boston, Cleveland, Kansas City, St. Louis, Dallas, Memphis, New Orleans, Milwaukee, Orlando,Houston,Detroit and Tampa.

People join gangs for various reasons, including:

Studies aimed at preventing youth involvement in gangs have identified additional "risk factors" for joining, including:

Gang membership was also associated with:

American gangs are responsible for an average of 48% of violent crime in most jurisdictions, and up to 90% in other jurisdictions. Major urban areas and their suburban surroundings experience the majority of gang activity, particularly gang-related violent crime.

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