Yes they do. In fact, many of the leaders are operating from behind bars at the max security prison system. They have a very well organized structure with extensive reach both in and outside the US which has made them quite formattable. I remember learning about them back in the late seventies when I was a administration of justice major in a CA college. Many LE agencies realized that CA had a huge gang problem and had to start addressing it through the formation of dedicated gang task force units and education. Prior to this, dealing with gangs was pretty much lumped into regular LE operations. It wasn't enough because the problem had grown exponentially.

Eme ruled the Greater Los Angeles area with an iron grip that had tentacles into areas like Orange and San Bernardino Counties along with their local affiliate groups and street gangs that handled more local issues under Eme's umbrella and supervision. The only other gang in the state at the time that could have been considered competition was Nuestra Familia in the Central Valley and Northern CA. They also operated out of the prisons. It was always messy when there were turf wars between them and it often spilled over.