I don't think I fully understood just how dominant gangs are in prison until I read this opinion.
Did I know they're pretty central? Yes. Did I know that members of rival gangs get separated? Of course. No one -- neither the prisoners nor prison officials -- want mortal enemies sharing a cell.
But I didn't realize the full extent of it.
For example, here, in Monterey County, there are separate portions of the jail -- separate dorms -- for (1) people who do not associate with gangs (i.e., people like you and me); (2) Norteno gang members and associates; (3) Sureno gang members and associates (the Norteno and Sureno gangs are the largest in California, and are enemies); and (4) gang members who are associated with "lesser" gangs (e.g., Bulldogs from Fresno or Hell's Angels).
So you get placed with your "type". Your friends. Your buddies. Or at least not your enemies.
To accomplish this mission, officials get information from the prisoners. They ask 'em what gangs they're associated with. They try to make sure they're not "dropouts" from the gang -- people who left the gang, since that means they'll be attacked if they're housed with members of the gang. Stuff like that.
But this isn't totally easy. Because if the prisoner admits he's part of a gang, that can be used against him at trial, and might lead to a pretty serious gang enhancement. So jailers sometimes have a tough time making sure they segregate the prisoners like they want.
So here's what they do. They have the prisoner fill out an inmate screening questionnaire (ISQ). They then take the inmate into the relevant gang dormitory -- in other words, they put the inmate into the "gang" they believe he belongs. Jail officials then put the prisoner on a second-tier bunk and make him fill out paperwork under guard.
During that time, the existing gang prisoners check out the new arrival. They decide -- under the watchful eye of the jailers -- whether the dude is in good standing with the gang. If he's not, "within seconds," they "roll him up"; i.e., assault him or otherwise turn him away. If he is, they leave him be. Either way, the guards then leave. They now know the scoop. If the guy's been attacked, they know he belongs somewhere else. If not, they know they've chosen wisely, and leave him there.
Ever see red ants and black ants placed together? Maybe as a kid? Or ants that might be from a different colony? Same thing.
Only in prison. With humans. Under the bureaucratic gaze and implementation of state officials.
One more thing. If the prisoner is not attacked, the state gets to use that fact at the defendant's trial. To prove that they guy was, in fact, a gang member, and hence may be subject to a gang enhancement.
I can only imagine what a visitor from another planet would think of all this stuff.