today, investigator franco domma arranges to meet a longtime source nicknamed washington outside city limits. they first began working together when washington was locked up on a gun charge. >> he was known to sell narcotic, have guns on him, shoot at people. i like a challenge. knowing we've been having problems with him in the past, let me give this guy a chance. what can he tell me? he's provide a wealth of information during during inkars nation, no time did he lie to me. i have five great informants and he's probably the best. not only does he tell me about the drugs, violent potential shootings, in the suburbs. i'm around the corner. see him in the black right there coming? got to be very, very eased up here. you see there's a lot of activity in this area. and i have to provide safety for him. yes, he's walking, looking around. looking around for safety. people are at him. he's looking to the left. to the right. once he makes eye contact, pull into an alley. see? he's flagging me down, right? you want to go to a location where we can debrief? sandoval, say there, sandoval. i'm c

. >> but investigator franco domma knows getting to the truth can take time. after vetting the intel they gather from inmates, ciu investigators share leads with outside law enforcement agencies. this training seminar's for suburban police. the purpose is to highlight the ciu's capabilities and help officers identify the gang spreading into their neighborhoods. >> guys, guys and girls we're going to get started. welcome to the sheriff's department. i'm an investigator here. i've been with the sheriff's office about 13 years. last two here in gang i worked all over the compound. a history on the cook county jail. this jail here's probably the largest single site facility in the united states of america. we have a daily population of 10,000 inmates. just about every incident in the jail is gang related. they do violations on their own members. they do hits on staff. they have 24 hours a day to think about ways to get over on us every day. what we try do here with the ciu department is track them. >> you can tell by your shag. that's good, man. respect for your o