. >> at san quentin state prison, we learned that not only do gangs force most of the prison population into racial segregation, they even draw boundaries on the rec yard. >> this is the lower yard. the inmates segregate themselves out here. the reason being that the gangs want it that way. the blacks are over here, the hispanics is our main gang here at san quentin. it's because they're better organized. the white guys over here an the parallel bars and the picnic table, over in the corner you see where the asians are sitting. >> you can't just walk and sit down at a table. i have to explain that. confrontation with that two or three times. i saw a table, i sat down. it's not like that. you got to ask for permission. >> even such a minor misstep can be taken as a sign of disrespect. and that can lead to widespread violence. though correctional staff is constantly on the lookout for weapons, it's well known that many on this yard are armed for battle and none more so than the northern hispanics. >> they have a minister of defense and his thing is he's to have ten weapons ready at any ti

. >> eventually transferred to san quentin state prison, the man who was arguably california's most violent inmate completed his sentence and was released in 2007. >> you have people locked up in this type of environment, then release them to the street, what do you expect? >>> next on "lockup: raw." >> they'll come across their enemy, slice them across the neck. >> the ingenious weapons inmates use to attack. phil! oh no... (under his breath) hey man! hey peter. (unenthusiastic) oh... ha ha ha! joanne? is that you? it's me... you don't look a day over 70. am i right? jingle jingle. if you're peter pan, you stay young forever. it's what you do. if you want to save fifteen percent or more on car insurance, you switch to geico. ♪ you make me feel so young... it's what you do. ♪ you make me feel ♪ so spring has sprung. >>> every day in america's prisons correctional officers are searching for them. >> a lot of these weapons were confiscated on the yards. >> in prison slang they're known as shanks. they are the deadly weapons that inmates create from behind bars with an ingenuity that almost de

few, though, made as lasting an impression on us as solon league of california's san quentin state prison>> i'm a third timer. youngster is a first timer. he got 12 years. i only got 13 days now. so i'm really preparing him to what's ahead for him. keep our house clean. >> league gave both his cell mate and our producer a lesson on the finer points of laundry behind bars. >> i clean my t-shirt. grab my bar of soap. dip it in the toilet. i keep my toilet fresh and clean. scrub it out. use soap. when your toilet fills up, it's fresh water now. i can just rinse it. i fold my towels. put it here. right up under here is my clothesline. >> league went on to give us a cooking demonstration using toilet paper like a stove top burner. >> take this. you sit it on the edge of the toilet. because it's got to breathe. might sit it here. i might light it at the bottom. as you see, it's like a fire. you hold your can over it. and you cook. there are, your water gets hot. flush it down. you grab a damp towel. because you don't want it to be on the toilet. you don't want to burn your toilet up. i get my b

. >>> it was graduation day at san quentin state prison. a real career once they are released from prison. ktvu's john sasaki tells us how they learned computer coding without the internet. >> reporter: two inmates led the way into graduation for code 7370. the program has thought them to be software engineers. >> a way for me trying to be a better person, help other people. >> reporter: he has been behind bars for 15 years after a drug related murder but now he is a graduate and he developed a web application. >> an idea that stemmed from my story of over coming substance abuse. developing a passion for fitness. i created an online life coaching service. >> reporter: they had no experience with coding and some never used the internet. this work and learning happen inside the walls of one of the most famous prisons in american, they do everything they do, learning to code, creating web applications with no access to the internet. >> i owe it to my victim and society to come out of here a better man. >> reporter: the accomplishment brought o

. >>> san quentin state prison graduated another class of computer coders on wednesday. we told you about this program a number of times. prisoners don't make license plates anymore, they write computer code. and then san quentin's entrepreneur's class presented their small business plans to venture capitalists. >> to begin with we sat down and drew out the framework of what we expected -- what story we expected the data to tell. then we selected a graph that we use as a canvas where we projected a map of the united states. >> these fellows are working on disease vector data to help map future outbreaks. this is an extraordinary program. it's already started to graduate its first students in the sense two of them have been since paroled and back out on the streets. and, vicky, they're working on their start-ups. >> scott, i know you were there in person. what was it like to meet some of those folks? it's pretty inspiring actually to see that they have this life 2.0. >> i am a convert to this idea of teaching people how to do things and rehabilitate them. the warden himsel

state seal. it was forged by inmate welders at san quentin from 1952. of the jails in prison that offer vocational trading, welding has always been aamong the most common about. 20 miles south of sacramento's downtown jail sits its branch facility. it's here inmate welders carry on the tradition. >> you get that 9:00 to 5:00 job feeling like you're back on the streets working a job. i've been on a hiatus the last ten years doing nothing. at 52, i guess it's time i start doing what i should have probably been doing years ago. >> overton is serving one year on his laters conviction, possession of a firearm by a felon. >> i haven't been in this jail since '90 something. i thought i would never see the inside of this one again. >> he served time in jail several times over the past 25 years on multiple counts of forgery, identity theft and drug possession. >> i've got the experience of welding. keep a job and get money put away finally instead of screwing around like an idiot like i have been a few years. >> the more experienced inmates take on jobs for outside clients such as thi

. >>> after inmates from san quentin are released, they return to society without the tools necessary to be successful on the outside. that's one reason the state prisonrate is higher than 54%. today ktvu met inmates who have a much better shot once they get out and there's a really good reason why. reporter: two prison inmates led the way to a graduation for what's called code 7370. the program has taught them to be software engineers. >> it's definitely a way that me trying to be a better person and help other people is my way of trying to make amends. reporter: chris has been behind bars for 15 years after a drug related murder. now he's a graduate of the coding program and he developed a web application. >> it's an idea that stemmed from my own story while in prison by developing a passion forfeit necessary. so i created an online life coaching service. reporter: he's had no previous experience with coding and had never used the internet. this man threatened someone with a gun and created an application. >> i code for eight hours a day here and then i can back to my bunk and i read for about another three or four hours -- hours a day. reporter: no