. >> the subject was clearly off the table when we sat down at pelican bay state prison with raul leon, alleged to be one of the leaders of the most powerful prison gang of all, the mexican mafia. >> how powerful is the mexican mafia here at pelican bay? >> i don't even touch on that right there. i don't speak on it myself. you know? >> raul leon had such influence throughout the state by assigning individuals to represent him. he would have people assaulted, he would have riots take place on his orders. >> serving a life sentence for murder, leon lives in what is widely regarded as the most restrictive environment in the state of california -- pelican bay security housing unit, or shu. inmates are confined to their cells for all but 90 minutes per day, which they're allowed to spend in a nearby concrete exercise area. leon had been living here for 14 years when we met him. >> i always tell people, ain't built a prison hard enough to break me, you know? and some of us are stronger than others. i think that's what pelican bay is about. only the strongest are the ones that are going to m