so jim davies began tracking dunkel. after kevin collin ss disappeared davies was able to confirm dunkel traveled from his home to the city. the night kevin went missing. >> i determined he was in san francisco not directly from john but from all of his friends. >> belmont police confirmed dunkel's movements that day. >> dunkel may be involved in, from my understanding they may have placed him in san francisco around the time collins boy went missing. >> davies tells me he tried to report that information to police who were heading the kevin collins investigation. >> they didn't want to hear what i had to say. it was that simple. >> oh, yeah. san francisco police to comment on jim davie as kt and give me access to the files but they refused saying it's an open investigation. but they couldn't tell me how long it's been since someone looked at the file. >> this is retired sfpd inspector keeps the collins information with him. he last worked the case in 2003, to see if kevin was a victim of the clergy abuse scandal. weaver

dunkel was old. and ready to put on a show. >> this is great. i had an urge to kill he took belmont police on a tour of his crime scene. >> and i killed him and placed his body on top of the mountain. do you want to just walk up the trail? >> he showed him where he stashed a murder weapon and seemed to get emotional, became annoyed by questions. >> what is going through your mind at the time? >> going through it. >> okay. >> belmont 1971 we never had a case close to this magnitude. it had the community locking their doors. disappeared from his home in the middle of the night. 12-year-old lance turner died near daytime soccer practice. 12-year-old sean dinel died in a sacramento park just after dark. police told media but they lackedtofdz make an arrest. their last resort paid off. >> when he moved to sacramento we planted a female detective in the fast food restaurant he was working in. >> she became his drinking buddy, wore a wire ask called for b whupe snuck into a home. e drunkel awaited trial on

. >> on the screen is scott dunkel. >> by the time he stepped in front of the camera john dunkel was25 years old and ready to put on a show. >> when i was in 6th grade i had an urge to kill. >> he took belmont police on a tour of his crime scenes. >> and i killed and placed his body -- >> did you want to take a step there or walk around? go ahead. >> he showed them where he stashed one of his murder weapons. he seemed to get emotional a couple times and became annoyed by the detective's questions. >> what was done here? >> i started in belmont in 1971. we never had a case that was even close to this magnitude. it really had the community locking their doors and wondering what was going on. >> 15-year-old john davies disappeared from his home in the middle of the night. 12-year-old lance turner disappeared from his shocker practice. sean danel disappeared after dark. and police suspected it him in each of the crimes. even told the media, but they lacked evidence to make an arrest. their last resort paid off. >> when he moved to sacramento we planted a female detective in the fast-food

. >> on the screen is scott dunkel. >> by the time he stepped in front of the camera john dunkel was 25 years old and ready to put on a show. >> when i was in 6th grade i had an urge to kill. >> he took belmont police on a tour of his crime scenes. >> and i killed and placed his body -- >> did you want to take a step there or walk around? go ahead. >> he showed them where he stashed one of his murder weapons. he seemed to get emotional a couple times and became annoyed by the detective's questions. >> what was done here? >> i started in belmont in 1971. we never had a case that was even close to this magnitude. it really had the community locking their doors and wondering what was going on. >> 15-year-old john davies disappeared from his home in the middle of the night. 12-year-old lance turner disappeared from his shocker practice. sean danel disappeared after dark. and police suspected it him in each of the crimes. even told the media, but they lacked evidence to make an arrest. their last resort paid off. >> when he moved to sacramento we planted a female detective in the fast-foo

atf special agent helen dunkel. >> this covers everything from canada, texas, west. >> this is the heart of the lab where analyst tries to find what ignitable liquides are used to cause explosions and fires. in a side room are samples, clocks, gun powders. also in this room this vault filled with all times of handguns and rifels. anything that fires a bullet. this marker in the lab that are different types of pipe bombs. >> that is what makes them so popular and prevalent. it's ease of obtaining the information. ease of obtaining components z ease of assembly. >> this chemist piecing together fragments.. >> two different pipe pieces. this is fit together. you can see pressure and everything how it works. >> the equipment is state of the art. this one provides 3 d images so analysts can look at every aspect of a case and firing pin. she finds a match with a cartridge from another crime scene. see how the lines are. >> this is both from the same gun. >> science is so intricate, scientists can determine if a tool was used to make a bomb or alter a firearm or to construct a homemade silencer

grandma's it dies, grandpa moves in, and san dunkel's. -- aunts and uncles.was great for the kids. probably hard for mom and dad. [laughter] i am the first united states senator i ever knew. [laughter] it was literally true until i ran. other than my opponent, i am the first united states senator i knew in my family. it is a typical american story. people say to me now and i wonder now, what ever gave you the courage as a 29-year-old kid to announce to the united states senate against a man who had an 82% favorable rating, in the year where we knew it would be tough, senator mcgovern knew it would be tough, it was solidly red, overwhelmingly republican, but gave you the courage to run? some thought that made you so foolhardy. the answer is your father. your father. i did not know him but i believed i could maybe go help him and the war. -- end tehe ware. i honestly believed it. what an incredible privilege it was to serve with him. i remember what frank church, i was on the foreign relations committee, the young kid on it. serving with your dad. we got a noti