California had prisons for nearly a century before the first documented gang — or security threat group — appeared, but now gangs run prisons — and the street, too:
Another common misconception about prison gangs is that they are simply street gangs that have been locked up. The story of their origins, however, is closer to the opposite: the Mexican Mafia, for example, was born at Deuel Vocational Institution, in Tracy, California, in 1956, and only later did that group, and others, become a presence on the streets. Today, the relation of the street to the cellblock is symbiotic. “The young guys on the street look to the gang members inside as role models,” says Charles Dangerfield, a former prison guard who now heads California’s Gang Task Force, in Sacramento. “Getting sentenced to prison is like being called up to the majors.”
But Skarbek says the prison gangs serve another function for street criminals. In a 2011 paper in American Political Science Review, he proposed that prison is a necessary enforcement mechanism for drug crime on the outside. If everyone in the criminal underworld will go to prison eventually, or has a close relationship with someone who will, and if everybody knows that gangs control the fate of all inmates, then criminals on the street will be afraid to cross gang members there, because at some point they, or someone they know, will have to pay on the inside. Under this model, prison gangs are the courts and sheriffs for people whose business is too shady to be able to count on justice from the usual sources. Using data from federal indictments of members of the Mexican Mafia, and other legal documents, Skarbek found that the control of prisons by gangs leads to smoother transactions in the outside criminal world.
Gangs effect this justice on the inside in part by circulating a “bad-news list,” or BNL. If your name is on a BNL, gang members are to attack you on sight — perhaps because you stole from an affiliate on the outside, or because you failed to repay a drug debt, or because you’re suspected of ratting someone out. Skarbek says one sign that the BNL is a rationally deployed tool, rather than just a haphazard vengeance mechanism, is that gangs are fastidious about removing names from the list when debts are paid.