911 emergency please. medical -- >> we have somebody that just came to our front door that's been shot in the head and needs an ambulance. >> reporter: it was 5:00 in the morning, somebody kicked in the front door of the house. >> reporter: inside, three young adults who shared the home. 20-year-old brienna campos, a college student studying architecture. her 23-year old brother remington campos, working as a mechanic. and a roommate, alex zaldivar, a 19-year old college freshman and aspiring fashion model. all about to become victims of a crime that should not have happened. >> and i'm hearing banging. like, someone's banging on the wall. i can hear pictures rattling against the wall. >> dude comes in, brandishes a gun right there. boom. there was bookshelves getting knocked over, drawers getting thrown.

>> and as i go into the living room, he throws me on the floor and says, "lay down with your face down. don't look, don't look." >> they were behind us. and you hear latex gloves getting put on. >> the next thing that came out of their mouth was, "it looks like someone's going to die tonight." >> reporter: die at the hands of a violent criminal who was awaiting trial. instead of jail, he was confined to his home wearing an ankle bracelet. something meant to deter crime. >> but the very authorities who were supposed to be monitoring it, not even on duty when the crime happened. thousands of people are wearing them, but who is keeping tabs on them, and who is keeping you safe? i'm david muir. >> i'm elizabeth vargas. thank you for tuning in tonight. >> reporter: everyone in the house, brienna, remington and alex were supposed to die that night, in this low-crime, neighborhood outside orlando, florida. the crime scene photos are too disturbing to be broadcast, and these are sanitized representations of what happened.

with no explanation as to why, they were lined up face down on the floor and then each shot execution style in the back of the head. the first bullet was for brienna. >> and then there's just ringing in my ear and intense pressure, not pain but pressure and then, when the ringing cleared away, i just feel the warmth of the blood on the side of my face. and i can hear it drip, drip, drip, drip, hitting the wood floor. and then i hear the second shot. >> reporter: that was for their friend, alex. remington knew that a third shot would be for him. >> well, you think about your whole life. and felt like a brick was dropped on my head. and i thought i was going to die. >> and then somebody said, "did you miss?" and i hear feet walk over to me. and i'm like, "oh my god they see me breathing." so i held my breath.

i play dead until i heard the feet walk away. and finally i peeked up and, like, the front door is wide open. and there's nobody there. and that's when i was like alex, you know, calling out to alex and my brother. and finally my brother popped up. and i said "we got to go." they ran out the back door, raced through the yard to the neighbor's house, desperate to get help for their friend alex who was still on the floor, unresponsive. >> it was tough. having to get up. and, you know, leave alex there. to go get help. to hope the ambulance can bring him back. but we had to go. >> are you responding? >> yes. pd is en route.

the ambulance is coming too. hold on one second. >> reporter: but it was too late for alex. >> he was dead on the spot. he was dead on the spot. he didn't have a chance. he bled out on that living room floor. >> reporter: alex's father, rafael zaldivar. >> we raised him for 19 years. and we lose him in two seconds, two seconds. >> reporter: somehow, brienna and remington survived the point-blank shots. >> it hit my skull, caused a fracture and then it traveled and then it popped out. >> and how about for you, remington? >> same thing. it travelled around the back of my skull and came out behind my ear. >> reporter: it was a miracle, doctors told them, and tonight this brave brother and sister are using that gift of life to come forward on "20/20" to help reveal the troubling story of how a career criminal was able to target them and kill their friend, after being let out of jail and put on an ankle bracelet monitoring system that

did not stop him. >> it could have been prevented. >> reporter: just one of some 50 murders since 2012 that a nationwide "20/20" investigation has discovered were committed, police say, by people ordered to wear ankle bracelets. >> they don't prevent crime. and they are not foolproof. >> reporter: former new york city and pennsylvania corrections commissioner martin horn. >> some have said it offers a false sense of security. >> absolutely there is a false sense of security. >> reporter: in the case in orlando, brienna campos had suspects in mind right away, even as she talked to the 911 dispatcher. >> and do you know who these people were that shot you guys? >> i can only think that they are probably linked to the people that robbed us last time. >> okay. >> reporter: the last time, was just four months earlier when police arrested this man, 27-year old bessman okafor, for tying up and robbing brienna and alex at the very same house and they agreed to testify against him. >> yep, i said 100% that's the man. and will you testify in court, yes i will.

>> did you think that could be trouble? >> no, not at all. >> reporter: but police say okafor knew the testimony of brienna and alex would have been devastating. he had built up enough of a criminal history that if found guilty of that offense, from the original home invasion he would've gone to prison for the rest of his life. at one point before the trial, brienna says okafor's mother even showed up at the house, trying to get her not to testify. >> she said she was willing to pay us money if we would drop these charges and not prosecute against her son. >> what did you say to her? >> i asked her to leave my property or i'd call the police. >> did you ever think "maybe i should just drop this whole thing." >> no. >> reporter: alex's father says his son was just as determined to take the stand. >> i asked him about that. i go. do you want to do that? he goes. yeah. i go, why? he goes because i want to do the right thing. >> reporter: and both alex and brienna were confident okafor could do them no harm, thinking he was securely behind bars while awaiting trial.

>> he was in prison, to my knowledge, the entire time. >> alex told me that they're in jail. they're not going to get out. okay, fine. >> so you thought and he thought they were locked up? >> locked up. >> reporter: but that was not true. and on the night before brienna and alex were scheduled to testify, they had no reason to think he was heading to their house to silence them. next, why was he free that night, and why were the people who were supposed to monitor him 24/7 at home in bed? depression is not just sadness. it's a tangle of symptoms. it's tiredness. and difficulty concentrating. depression is multiple symptoms that can hold you back. my doctor prescribed trintellix. a prescription medicine for depression. trintellix may help you take a step forward in improving your depression. tell your healthcare professional right away if your depression worsens

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in the film "disturbia," with shia leboeuf, people on house arrest with ankle bracelet tracking devices find the police racing to the scene when they go even a few feet over the line. >> no, no, no sir, listen, officer, listen to me, i wasn't trying to go anywhere, i wasn't trying to leave. >> put your hands behind your head. >> reporter: it was the same quick police response in the movie "cherish," but something we found too often just a hollywood movie. >> it's amazing, right? i wish it would have worked that way. >> reporter: it doesn't? >> of course not, it's a joke. >> reporter: as the father of alex zaldivar discovered only after his son was murdered by a man wearing an ankle bracelet. the killer set free on bail by a judge, who trusted the device would keep a career criminal under house arrest. >> i couldn't believe it. not only did i have to deal with the execution of my son. then i found out he's wearing this device that should prevent him from leaving his home. and that's when i started my investigations into the ankle

monitoring business. >> reporter: it's become a thriving, international business with private companies in the u.s. selling the device systems to local and federal government agencies in every state. some 300,000 people are estimated to be wearing ankle bracelets tonight. as seen in their promotional videos, the companies do the monitoring at national centers and then send alerts to local authorities if the people wearing the bracelets violate restrictions or try to tamper with the device. >> any attempts to open the bracelet are detected and reported immediately. >> reporter: marketed as a way to enhance public safety and to save money by reducing the number of people sent to jail. bringing big profits to the companies involved. >> they're making money. my son is dead and they're making money. >> bessman, my names mike moreshi, i'm a detective up here. >> reporter: bessman okafor, the man who police suspected killed zaldivar's son, was still wearing his ankle bracelet when

he was brought in for questioning that same day by orlando police detective mike moreshi. >> you have that thing connected to your ankle still, right? >> yeah. >> it is still there? >> yeah. >> reporter: in fact, police would later determine okafor was wearing it as he and his accomplices drove to the witnesses' house in the early morning hours. >> were you at that house again last night? this morning? >> no, sir. >> reporter: there are many versions of ankle bracelets, and okafor knew his could not track where he went, but simply sent an alert if he left his house. and he denied any involvement. >> i have nothing to do with what's going on. i have nothing to do. >> reporter: records show there were three alerts the night of the murder, as okafor left his house. the last one at 4:40 a.m., about a half hour before alex was killed, but no one saw the alerts because incredibly for budget reasons, there was no one

on duty after 9:00 p.m. at the corrections department to monitor the ankle bracelet cases, to the disgust of homicide detective moreshi. >> were police cars dispatched to pick him up? >> no. >> reporter: that's not how it worked? >> no. >> reporter: the records show okafor's ankle bracelet had set off some 106 alerts even before the night of the murder, but no action was taken against him and the judge was not notified. >> i'm not sure what the purpose of it was because he had had so many curfew violations and didn't get violated. >> reporter: so he just learned he can do anything and it didn't matter? >> right. >> reporter: it was high drama in the courtroom as okafor went on trial raphael zaldivar was there every day, barely able to contain his rage over the murder of his son alex. >> you're dead! you're dead. i wanted to kill him. i wanted to get my hands on him. >> reporter: and now, instead of testifying about the initial robbery, brienna and remington were testifying about their

friend's murder. >> then once the ringing stopped ringing in my ear and i realized that i was still alive, i heard a second shot. >> i've seen him die. >> reporter: the verdict was quick and the sentence harsh. >> as to count one of the indictment, first degree murder with a firearm of alexander zaldivar, the court sentences you to be put to death in a manner prescribed by law. as to count two of the indictment -- >> reporter: zaldivar saw it as justice for his son, but he was far from done, as the retired marketing executive turned his rage towards the county officials who ran the ankle bracelet program. >> everybody who's involved in my son's case, that failed him is responsible. he had a right to live! >> reporter: his first question, why was he put on an ankle bracelet to begin with? >> he's a predator, habitual predator, and they're telling him to stay home and be a good boy until your trial comes up.

>> reporter: wearing an ankle bracelet? >> yeah. this guy shouldn't have been on the streets. >> reporter: his next question, why was no action taken after the more than 100 times okafor violated his curfew? do you blame the people who ran the ankle bracelet program here as much as you blame okafor? >> of course. >> reporter: really? >> yeah, i do. >> reporter: he's the one who pulled the trigger? >> yeah, he sure did. you know, but it was their responsibility to follow up on him and to keep him away from my son. >> reporter: with zaldivar's unrelenting pressure -- >> they didn't do one -- thing, nothing to save my son. >> reporter: and follow up investigations by orlando reporters the three senior county officials responsible for the ankle bracelet program either resigned or retired. >> i had to take everybody to task. >> reporter: you were on a tear? >> i was on a tear. i was ripping it.

>> see this tracker and um i just want to show you guys how to remove it. >> recently, i came into possession of an ankle monitor. i just found it. >> reporter: and then zaldivar made a startling discovery on youtube, all kind of videos from all kinds of people, supposedly showing how to get an ankle bracelet off. >> put the foot in the freezer and try to close the door. >> you're going to scrape off some of the rubber off of one side to expose the wire. >> you can use a nail clipper. that thing in the back, watch this. >> oes oh, it's getting cold. >> you're going to cut right here. >> remove the foot, knock three times. >> they put vaseline on their ankle, just slip it off and put it on the dog. >> reporter: even though the bracelets have been upgraded over time, we're only showing a small part of the process. >> in the criminal world, they know the limitations of these devices far better than you or i ever will.

and it's a struggle to stay one step ahead of them. >> just run outside and enjoy your free time. >> reporter: and as his investigation continued, zaldivar began to discover dozens of other cases involving violent crimes committed by people being monitored by ankle bracelet systems. it wasn't just his son. >> i focused just on homicides. it was not a local problem, it was not a state problem, it was a national problem. it's an epidemic. >> reporter: next, as he launches a crusade to expose the problem, zaldivar discovers a case that shocks even him. >> it's a spooky thing. i'm trying to figure out what's going on here. >> reporter: what's going on? this is important for people with asthma. yes. what's going on? to help prevent severe asthma attacks, and lower oral steroid use. about 50% of people with severe asthmhave too many cells called eosinophils in their lungs.

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>> reporter: for some celebrities, it's like a fashion accessory, something to show off to the paparazzi. the bad boys and bad girls of the tabloids, actors lindsay lohan, michelle rodriguez, teresa from "the new jersey housewives," rapper comedian andy dick, all ordered to wear an ankle bracelet to monitor their location, or in some cases, alcohol use. along with martha stewart, tracy morgan and the famous for being infamous paris hilton. perfect candidates all, hardly risks to the public.

>> in the beginning, it started like that and then it progressed. >> reporter: progressed, discovered raphael zaldivar, to include individuals who are hardly low risk. in an effort to keep down the costs of putting so many people behind bars. >> they give them to child molesters. child molesters. >> reporter: in the investigation, zaldivar was shocked to discover what happened with a man living in this quiet neighborhood in syracuse, new york, where neighbors were unaware that a monster was living next door. >> he is the embodiment of evil, the embodiment of evil. his whole life he's committed actions that make him evil. >> reporter: at the age of 29, david renz, a part-time grocery store clerk, was wearing an ankle bracelet as he awaited trial on federal charges for possession of a huge cache of violent child pornography, desperate to get away from his home, if only he could find a way to get the bracelet off. >> he was experimenting with what he could get away with. and he was loving it. >> reporter: leading to a crime that would horrify the

community. >> syracuse is a great city and a great community but, it's a small community. this ripped the soul out of us for a long time. >> reporter: in a remarkable video deposition conducted after the crime, renz with an ankle bracelet next to him, matter of factly admitted how he gained the freedom to commit his crimes. >> did there come a point in time when you were able to take the bracelet off? >> yes. >> reporter: the model he was wearing is marketed as tamper resistant, but renz said, in part, he learned how to get it off because the probation officers let him watch as they put it on. >> instead of telling him, you know, turn your head or put a paper bag over his face or something. >> reporter: district attorney william fitzpatrick would later prosecute renz for the crimes he committed. >> they were treating this guy as if he had been picked up for shoplifting a box of donuts. >> how many times in total would you say that you took the bracelet off from the time you first took it off until march

14th of 2013? >> i can only give an estimate, but i figure probably ten to a dozen. >> at any point in time when you had the bracelet off, uh, did you leave your home? >> yes. >> reporter: and when he left his home free of the device, renz began to prepare for his crime. first, with a trip to a local home depot. >> what did you go to home depot for? >> to purchase zip ties. >> reporter: zip ties, to be used as plastic handcuffs. and then to walmart. >> and when you went to wal-mart what did you purchase? >> that would be an air soft gun. >> reporter: an air pistol like this one, looking like the real thing. >> when you went into walmart to purchase the air pistol on were you wearing the ankle bracelet? >> i was not. >> reporter: it was in his bedroom. it had sent a tamper alert when he took it off, but renz knew how to quickly tape it back together so the signal was restored.

>> this guy figured out how geththing off and reconnected in less than a minute. >> reporter: and federal probation officers overseeing renz were treating any interruption of less than five minutes as a false alarm, complaining in this phone call about the devices. >> my officers are getting frustrated with the reliability. >> reporter: telling the monitoring company, even before the renz case, not to bother them with alerts less than five minutes, saying too many false a alarms were costing them sleep. >> do you want me to put something in for five minutes? >> yes. >> ok, and that would take care of the alerts so that they wouldn't be, you know, woken up in the middle of the night because. >> yeah, like last night. >> reporter: so each time renz took off the bracelet and left his home, it was treated as yet another false alarm. >> this case is sickening because it was so preventable. it never should have happened. >> can you tell me at any point in time when you had the

bracelet off, did you ever receive a call from the federal government, the u.s. probation department? >> no. >> reporter: on march 14, 2013, renz again left his home, taking with him the air gun and the zip ties he had collected for his well-planned crime. his ankle bracelet was left behind. renz's destination that night, a 10 or 15-minute drive away, the great northern mall, a popular, family-friendly place with a gymnastics facility for kids and parents. he took a position in the vestibule of the front entrance. and soon spotted his targets. he followed them through the parking lot. >> he was able to get to them and pull what they believed was a gun. and get in the back seat and carjack them. >> reporter: a night of terror was about to begin. seven miles away, his ankle bracelet was in his bedroom, sending a message that all was well.

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it was a dark, cold, inclement night. bill cregg, a roofing contractor in syracuse, new york was on his way home. >> as i was driving, i caught out of the corner of my eye, this young person running through the wood line. i continued to drive a little bit further, and probably a

couple of hundred yards down on the right hand side there was a car off into an access road. and i was like something just isn't right here. it's not adding up. >> reporter: an army veteran, trained to handle the unexpected, cregg new he had to turn around and find out what was happening. >> and there was a young girl. and she was screaming that. "he's going kill my mother." >> 911 where is the emergency? >> there's a little girl tied up on the side of the road, and a woman bleeding. it's a spooky thing, i'm trying to figure out what's going on here. >> what's going on? >> reporter: a little girl's voice in the background, he hurt me. >> he hurt me. >> i walked towards her and she immediately began to scream, "are you going to hurt me are you going to hurt me?" >> no, look. i'm not going to hurt you. i am on with 911, okay. honey? >> i gave her my jacket. i put her in the back seat. she had her hands behind her back with zip ties. >> we're not leaving your mom. i want you to get warm, honey. what's your mommy's name?

lori bresnahan? >> reporter: lori bresnahan, a devoted single mom. >> she was wonderful. very, very big heart, very giving person. always very involved in her church. librarian in three different school districts once she adopted her daughter. her daughter was her whole life. >> you could see it when lori would talk about her. her eyes would light up and when her daughter would look at lori, the same, the same thing. >> just the pride and the love that, yeah. yup. >> reporter: after being carjacked at the shopping ll with her daughter, lori had been ordered to drive to a darkened, deserted area. >> he tries to strangle her with the zip ties. and the zip ties keep on breaking. >> reporter: new york state police investigator, todd grant. >> lori, you know, god bless her soul, is able to yell out "run and get away," to the ten year old. >> sir, can you see the mother

at all? can you see if she's breathing? >> i'm going to check right now. >> reporter: she had been repeatedly stabbed and was bleeding heavily. >> she was in bad shape. real bad shape. nothing i could do for her except keep her comfortable. >> keep breathing for me, sweetie, you're doing super, okay? >> reporter: at this point, police had no idea who was responsible. no idea that a man who was supposed to be confined to his home, wearing an ankle bracelet as he awaited trial on child pornography charges, was actually on the loose, the bracelet left behind. >> it's our belief that he was intending to kill both lori and the 10-year-old. >> reporter: the 911 dispatcher asked cregg to get a description of the attacker from the little girl. >> you're doing really good, sweetie. i want you to go slow. was he white, was he black? >> he was white. >> he was a white mail. do you remember, was he my height?

about 5'10'', ma'am. was he heavy, was he skinny? he was skinny. >> reporter: and now the search began. >> i knew that the perpetrator of this crime was still on foot. i knew that he was in the woods and i knew that we were going to have to go in there after him. >> reporter: led by sergeant jeff cicora and his canine partner, dozens of police combed the woods that cold night. >> we knew that this guy had just committed a horrible act and he was desperate, and he had no place to go, and he was on the run, and he knew we were behind him. >> reporter: as the search was under way, word came about the fate of lori bresnahan. bre >> she didn't make it? >> no, sir. no. lori, i think continued to fight to her very last breath to make sure that her daughter was going to be safe. and she succeeded.

i told her that i would promise that nothing wou ever happen to her again. >> reporter: four hours later, david renz was in custody. >> i knew that we had just caught a true monster. >> reporter: and then the added outrage as police discovered he was supposed to be at home, wearing an ankle bracelet meant to protect the public from a man like this. >> had we not caught him that night, he would have gotten home. had he gotten home he would've had the perfect alibi because his bracelet was left at home. he would've had the perfect alibi. >> reporter: for the good samaritan, bill cregg first on the scene, it would change his life, vowing to honor the memory of lori bresnahan and to find out for her daughter what went wrong. >> i say lori deserves answers, the little girl deserves

answers. make sure what happened in upstate new york doesn't happen in any place else. >> reporter: but it has and it does. next, police in hot pursuit, the story behind this car chase. ♪ music playing ♪ je plonge à l'envers attiré par l'extase ♪ ♪ un tourbillon vert illumine les sirènes ♪ ♪ ♪ oh la fête fo', fo' ♪ ♪ ♪ oui l'endorphine s'est envolée ♪ ♪ ♪ d'une fête foraine devenue noire ♪ ♪

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southbound, 100 miles an hour. >> reporter: a police chase along 237 in texas, in hot pursuit of the man driving the cadillac, a killer. >> he just fired at the deputy. >> reporter: yet another criminal who was able to beat

the ankle bracelet system to carry out his crimes. leading to a dramatic end as he crashed into a tractor trailer. >> major accident. >> reporter: his life on the run, finally over as police moved in, returning fire. the man they finally stopped was evan ebu, recently released from prison in colorado who had cut off his ankle bracelet. it sent a tamper alert, but it wasn't until five days later that a probation officer went to his house toheck it out. giving him enough time to kill a pizza delivery man, and then the head of the colorado prison system. those two murders in colorado are among the some 50 murders since 2012 that a "20/20" investigation found were committed, police say, by people being electronically monitored. >> i suspect there are more you don't even know about. >> reporter: from your point of view, there is no reason this

should be used for anyone who poses a risk to the public. >> none whatsoever. that's right. >> reporter: yet it is being done based on what we have found. >> i'm afraid that's true. >> reporter: among the 50 cases we documented, one just this week, a baltimore county police officer, killed, authorities say, when she was run over by a teenage burglary suspect she was trying to stop. he had been ordered to wear an ankle bracelet after a series of arrests for car theft, but went missing five days before the officer was killed. >> dante harris will be tried as an adult. >> reporter: case after case of failure. >> after cutting off their gps ankle bracelets. >> he also had an ankle bracelet. >> the court ordered madonna maguire's husband to stay away from her. >> reporter: in one case, officers actually put the ankle bracelet on a defendant's artificial leg which police say he took off and put on a spare to go kill his victim.

he is awaiting trial. >> this is not a shortcut and it's not a sound way of saving money. >> introducing bi analytics. t >> reporter: the biggest is called bi, under a corporation that runs private prisons. they say it enhances safety, saves money and provides social benefits. >> they allow individuals to be at home and working with their families and in the communities that don't necessarily need to be locked up. >> this is what we're going to utilize to track your movement when you are out in the public. >> reporter: the company helped to arrange a demonstration in phoenix who put a bracelet on me. >> snug on your ankle. >> reporter: once i went outside a restricted area. >> when you hear that sound right there -- >> reporter: the bracelet sent a signal to the monitoring center and there was an audio alert.

>> exiting the zone. leave now. >> reporter: they have time to quickly respond at any hour. >> i first want to note that public safety is only as good as the supervising entity we provide our products to. >> reporter: when it is not good, the results can be tragic. when david renz cut off his bi bracelet, the tamper alert was treated by local authorities as yet another of the false alarms plaguing the office. at the time of the murder, bi was in the process of an upgrade for the ankle bracelet version that renz was wearing, but it came too late for lori. >> david renz proved to us that he could take it apart and put it back together in less than a minute, and this is the technology that we're giving to monitor felons? it's a travesty. shouldn't have happened. >> reporter: since that cold, february night when bill cregg

stopped to help, he has been doing all he can to bring public attention to what happened here. >> i would never forgive myself if i sat on my couch and saw this happening someplace else without trying to do something. >> reporter: that has been the mission of raphael zaldivar too in the wake of his son's death. should anyone put faith in these ankle bracelets? >> zero. absolutely zero. >> reporter: but until now, no one in washington has kept track of all the crimes committed or has been paying much attention to the problem. last week, that began to change as bill cregg from syracuse, and raphael zaldivar from orlando teamed up for the firstime to carry out their shared mission. they met with their local members of congress, the staff of the senate judiciary committee, and a former prosecutor and democrat on the house judiciary committee. >> i'm sorry you're here, and

i'm glad you are here. i'm moved by their passion, two people who have tragically seen what can happen when this goes wrong. >> that's your son? >> our son, alex. >> there are people killed over the last few years, and that means we have gotten something wrong, in who we are allowing to wear ankle bracelets. >> reporter: the man convicted of killing alex will get a new hearing later this year on his death sentence. brienna campos and her brother, remington, are more than ready to testify against him again. >> waiting for a call. >> yeah. yeah. it's going to get done either way for alex. >> reporter: raphael will be in court too, still pushing both for justice for alex and a change in the way ankle bracelets are used in this country. a vow he says he made to his son on the day he died. >> i told him, someday i'm going to be on "20/20," and here we are.

that was my mission. to make sure it doesn't happen again. just as i promised. forever in our hearts. >> a man with a mission. we can report tonight that the little girl is with family and doing well. >> and we are so glad to hear that. when we come back here tonight, we're going to switch gears depression, it leaves me... feeling sad... and empty. it makes it hard to be there... for the people i love. so i talked to my doctor, and she prescribed latuda. latuda is fda-approved... to treat bipolar depression,

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fthere's flonase sensimist.tchy and watery near pollen. it relieves all your worst symptoms including nasal congestion, which most pills don't. and all from a gentle mist you can barely feel. flonase sensimist. and timely tonight here, a bittersweet moment for us. after 22 years here at abc news a news anchor at "gma," a co-anchor at "world news tonight," and leaving her mark here on "20/20," tonight, elizabeth is about to start an incredible new chapter. at home, i know you will feel just as i do about this because elizabeth has guided us through so many, so many important moments from 9/11 taking over, to hurricane katrina. >> that's right. i was in mississippi. you were in new orleans. we have done so much together, and i have been able and privileged to work through so many incredibly big breaking news stories and really

important personal stories that we have done here on "20/20," and i'm very grateful for all the opportunity i have had here, and to work with all the people whom i call not just colleagues, but friends. but i'm moving to a&einvestigates and we start work there on monday night actually. >> you will lead the way there as you have here. on a personal note, i just -- if you will let me, i want to share a little bit about the woman i know behind-the-scenes here. the devoted mom, a determined journalist and more important than that for me, you are someone whose own bravery has given a voice to someone who needs a voice. you know how i feel about you. i miss you already. >> thank you. thank you so much. >> take a look. ♪ >> this is ground zero. >> what do you hope for in your life? ♪ >> something extraordinary happened in that courtroom

because of you. >> reporter: from the very start here at abc, it was her curiosity, and her love of journalism. >> i'm elizabeth. nice to meet you. >> you too. >> why don't you have a seat? >> reporter: we first met her on "good morning america." >> the newest member of our "good morning america" family -- >> the new face, new desk, new news, elizabeth vargas with us. lots of news in that sentence. >> lots of news. good morning. it's nice to be here. >> reporter: on the air, in the hours after 9/11, picking up where peter jennings left off. >> elizabeth, thanks very much. >> abc news continuing coverage of that terrorist attack on the united states. >> reporter: amid the destruction of hurricane katrina -- >> in the next hour, we'll go to many of the hours most decimated. >> reporter: she made her mark in the morning. ♪ and at night, she would co-anchor "world news tonight" with bob woodruff.

>> on "world news tonight." >> so deliver the news straight to you. >> reporter: covering the iraqi elections, interviewing president bush from the white house -- >> thank you. so obviously this is the wash and this is where they cook. >> yeah. >> reporter: but along the way, her most indelible mark has been on this program, "20/20" where barbara walters passed the torch. she is the only other woman than barbara to co-anchor this program, and also highlighting her connection with children. >> oh, she is so beautiful. >> reporter: there were the children held hostage in russia. they watched as more than 300 adults and children were killed around them. >> what do you say to each other to comfort each other? >> translator: i said they are going to let us go soon. >> how about you boys? >> translator: we say to each other that everything is going to have a good ending. >> reporter: there were the wolf pack brothers who spent their

lives locked away from the outside world. >> you have seen 10,000 movies? >> at least. >> wolf pack, meet robert de niro. >> reporter: and it was elizabeth who introduced us all to this remarkable little boy, born with a rare cranial facial difference. >> i'm curious when you realized, hey, my face is different from other people's faces. >> when the first kids called me a monster. >> a kid called you a monster? >> yeah. >> why do you think kids do that? why do you think they say mean things to kids who look different? >> they don't know what to say, and their parents don't really do anything about it. >> do you have a moment please? >> reporter: elizabeth has never shied away from asking the tough questions. >> just a moment. why are you asking for life imprisonment for amanda knox? if you are lying to me about that, what else might you be

lying to me about? >> reporter: and in recent years, she would share her own story. revealing to diane with brutal honesty, her battle with alcohol and anxiety. >> there is a favorite saying i heard that was, you know, when you pray to god, there are three answers. one is yes, not now and, i have something better for you. >> reporter: the audience would reach out. she heard from so many of you, saying her courage to get help inspired many of you to do the same. she returned to that desk for some of the most important moments in recent times, and for me, she was always a force to sit next to, a true partner. ♪ >> yeah. hi, munchkin. hello. hello. >> is she blowing you kisses? that's so sweet. >> reporter: as elizabeth now embarks on her newest chapter, reporting breakthrough hours, we salute her, her strength, her

courage to open up and always her love of journalism. >> you clearly love your country. i don't want to make you cry. ♪ >> thanks a million. >> in the meantime, that's our show tonight. thank you so much for watching. for all of us and david here at abc news and "20/20," have a good night and a great weekend. ♪

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