. >> such was the case with epi cortina. he joined a street gang at age 11. it led to a 16-year to life sentence for murder. >> i've been pelican-bay raised. been up here going on 14 years. >> he'd been in prison since he was 19. he was 32 at the time i interviewed him. and he'd just been through years and years of just senseless violence. >> after his arrival at pelican bay, cortina, like many other hispanic gang-bangers from northern california, joined a prison gang known as nuestra. familia. >> i walked into a war atmosphere and i was all for it. let's go, strapped on the boots and let's go. so three months after coming to pelican bay, i was assigned squad leader because squad leader is i'm in charge of educating other people on the bombs, the format, how to make knives, how to stab people, where to stab people, what would be the best times, exercising and making sure everybody's following the guidelines of our gang. right? >> i almost felt like it must have been what it was like 10,000 years ago when you have this almost tribalism. and you have to rely on