Prison gangs in America were formed for protection. Their main goal, just like other fraternal groups, was to be protected and respected inside the prison, where most prison gangs originated. These gangs are highly organized. Their powerbase is usually outside the prison, where new members are being recruited by their street-gang members. 

There are times when a prison gang outgrows the penitentiary life to take on some unlawful acts outside the prison. There are others that are being transplanted from the street. But one distinct characteristic of a prison gang is they are highly race oriented. There are at least three main racial gangs in continental America: Hispanic, Black, and white supremacist. 

In America 90 percent of vicious crimes in other jurisdictions and 48 percent in jurisdiction areas account for gang activities. Some gang-related incidents include: white-collar crimes such as fraud, identity theft, and counterfeiting; prostitution; drug trafficking; gambling; human trafficking; and arms trafficking. 

Although they are known for being notorious criminals, prison gangs offer a benefit for the police officers inside the prison. They are responsible for the discipline of their members, which helps reduce internal conflicts and violence despite the strong tension.