. she was an 18-year-old girl. it broke my heart. it destroyed me. what do you do? you just keep fighting. >> heidi allen was sweet, spirited and super smart. >> test tomorrow, no sweat, huh? >> yeah. >> she took a job here to earn cash for college. >> she wanted to be responsible. >> she was working the early shift on easter sunday. that's when she vanished. >> they called from the store, they can't find heidi. >> they noticed somebody wrestling with somebody in a van. >> the theory became two brothers did it together. >> mystery solved? maybe not. years later during a chance encounter --

>> he said, you really want to know what happened to her? >> a horrifying story. >> he said, i grabbed her like this. >> an old case blown wide open. >> i said, we can't let this go. >> two women, teaming up for the truth. >> if they think i'm going to walk away, they are mistaken. >> uncovering an astonishing twist. >> attached was a photograph of heidi allen. it had a code name, julia roberts. >> a teenager with a secret identity. did she also have a secret enemy? >> they're going to want to shut her up permanently. >> i'm lester holt and this is "dateline." here's dennis murphy with "the informant." >> tonya priest never wanted to be a star witness, least of all in a long-ago abduction and murder investigation. but after that guy blurted out what he did, she felt she had to come guard. >> would you you live with it? could you live with all of that? >> and she found herself on the

phone talking to a district attorney in upstate new york. >> i know the truth, sir. >> tonya believed she knew who done it, who done that terrible thing at the convenience store on an easter sunday morning many years ago. that store clerk abducted and never seen again. >> they probably only took maybe 60 seconds to do what they needed to do. >> what tonya reopened was a wound that had never really healed in oswego county, new york. >> i can't let it go. i won't let it go. >> i will die trying and fighting for her. >> if they think i'm going to walk away, they are mistaken. i am not. >> even today just say the name heidi allen and a swirl of memories come back. some of them fuzzy now. it was 1994, that missing girl, the van, was it blue or was it white? and didn't they get the guy who

did it and send him away? tonya was a teenager back then. >> did you follow it in the news or did kids talk about it in school? >> i knew they were looking for a van. that's basically all i knew at that point. >> here's what's not in dispute about that snowy easter sunday morning. 18-year-old heidi allen, taking the early shift for a coworker, opened the convenience store about 5:45 a.m. it was a part-time job for her. a way to defray some of her freshman college bills. lisa is heidi's sister. >> she was sassy and energetic and a risk-taker. >> did she like school? >> she liked school. she didn't have to study. she was a smart kid. >> bhafs about the convenience senator. >> it was close to home. our friends owned it so mom and dad felt safe. >> before the early birds started showing up for their newspapers, cigarettes, a few

gallons at the pump, heidi's boyfriend was there. >> he would take her so the people -- when traffic was picking up, and then he would go. >> that's what happened that day. >> yes. gary thibodeau saw her. >> i was there for two basic packs of cigarettes, paid her. i said, have a nice day. >> a few more cars pulled up to the store. reporter john o'brien of syracuse.com. >> some customers had come in and didn't realize she wasn't there until they had been there for a while. they flagged down a deputy and no heidi. >> heidi's sister lisa woke up that morning to very bad news. >> my aunt was on the machine and she said, lisa, heidi's missing. >> missing. >> we saw her the night before. when she delivered our easter baskets in her usual goofiness. >> it was shocking an

18-year-old girl could just disappear like that on easter morning. >> the convenience store was strung with crime scene tape bit time heidi's sister arrived. >> i just really felt like i was watching a movie. inside the store, not promising. they found heidi's purse, her car keys, money undisturbed in the register. no signs of a struggle and her car was parked in the lot. >> i just remember sitting and just watching. i didn't know what to do. >> the community made a "find heidi" volunteer command center at the old fire house while authorities readied their first news alert. >> we have an 18-year-old girl bit name of heidi allen who lives here in new haven, who was the clerk. >> someone listening to that bull ton was richard thibodeau who recognized heidi from the convenience store where he shopped earlier. he turned to his girlfriend, theresa, and said as much. >> and richard said, my god, i

was there. i bought two packs of cigarettes. he picked up the phone and called. >> called the sheriffs and set in motion a sequence of life-changing events he could not stop. other callers that morning offered tips about a suspicious van at the store. the sheriff was under-sheriff at the time. >> they noticed someone driving very erratic, wrestling or struggling with somebody in a van. >> this van, sheriff, did you get a make, model, color, anything? >> different color, blue, light blue. >> in the early hours, in the days before smartphones and ubiquitous security cameras, nothing was coming together. volunteers searched, the national guard was called out. but heidi was gone and stayed gone. >> we followed up on every lead. we had no major people. >> weeks went by without an arrest, without answers. and then a couple of months passed. they had brought in a criminal profiler with the fbi's

behavioral science unit. someone who would later correctly profile the oklahoma city bomber. but in this instance, clint van zandt was the agent in the unit who got assigned to the heidi allen case in upstate new york. his take, look for someone with a history of violence and someone obsessed with the case. >> the person who committed this is somebody who was really interested. i mean, the community was interested in the case, but this is mosh interest. >> obsessed? >> could not let it go. this is someone who would be saving newspaper articles. >> and there would be many newspaper articles. decades of them, in fact. the case of heidi allen was just getting started. >> when we come back, clues to the mystery. >> who would grab an 18-year-old girl? >> our theory then was probably a sex crime. >> and then, unbelievably, the killer seems to out himself. >> he says, yeah, i killed this girl. >> he gives it up. >> he gives it up. my hygienist said the most random thing.

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heidi, the teenager behind the convenience store counter selling sunday papers and cigarettes had vanished that easter morning. sheriff reuel todd. who what was your working theory? who'd grab an 18-year-old girl? >> our theory then was probably a sex crime. >> reporter: abducted, and after

weeks of fruitless searching, presumed murdered. >> she's the 18-year-old girl that had her life taken from her. she was a good kid with goals. >> reporter: but the sheriff's department was pursuing a promising lead. and it concerned a guy who had bought cigarettes from heidi that morning, richard thibodeau. did the cops on the phone start to ask you questions? >> they sent someone over to the house and asked me a bunch of questions. >> reporter: investigators, it turned out, were suspicious of him from the get-go. they'd even put him under surveillance. the reason? thibodeau's was the last transaction recorded on the register that morning and richard thibodeau also drove a white van, one that seemed to match a vehicle described by a witness at the scene. >> at first it was blue. it changed to white as time went on. but he did say in the end that van, the thibodeau van, that was the van. >> reporter: the witness reported seeing more than one man, so investigators also brought in richard's brother, gary, for questioning. the brother said he was home asleep that morning and his girlfriend vouched for him.

but gary thibodeau didn't have a spotless record. he had an outstanding warrant on a minor drug charge in neighboring massachusetts. >> they extradited him to massachusetts, which was an odd thing on a drug charge. >> reporter: in the county jail, thibodeau struck up a conversation with a fellow prisoner. >> him and gary are sitting in there shooting the breeze, and they get talking about something like all of them do. he says, yeah, i killed this girl from oswego. >> reporter: he gives it up, though? >> he gives it up. >> reporter: brother gary is eventually said to have told two prisoners about his involvement in the crime. that he and heidi used drugs together and that she feared gary was going to screw her over in a drug deal. and with that jailhouse confession, investigators now believed they had their case. the two brothers, drugs, an abduction and murder. >> i was waiting for my school bus to come. >> reporter: this is richard thibodeau's step-daughter, amanda. she was just 11 at the time. >> and police cars came pulling into my driveway.

i don't know how many, but they just came shooting right in and stopped quickly. >> reporter: both brothers were arrested and charged with kidnapping in the first degree. >> a major break in the heidi allen case. >> reporter: what's the motive, sheriff? what's the theory that goes with them in their van and being at the convenience store? >> do you know what the motive is? opportunity. they stopped in there to get the cigarettes, and that was the opportunity. >> reporter: it's about abduct this young, cute girl, huh? >> appears to me. >> reporter: there would be two separate trials for the brothers. two separate juries to decide their fates. and in the summer of 1995, the first of the two, gary, went on trial. joe fahey, now a retired judge, was gary's defense attorney. he says the case was forensically and circumstantially light. >> there was no indication that gary had ever been near the d&w that morning. >> reporter: gary testified that he was home asleep that morning. and the jailhouse snitches who got him indicted were flat-out lying. he figured they must have been

angling for favors from the prosecution. >> the only thing they really had to contend with were the two guys from massachusetts. they said gary kind of boasted about they were looking for me, but they'll never find her. >> reporter: but they were statements a jury apparently believed. it took just four hours to render a verdict. >> how do you find the defendant on count one kidnapping in the first degree? >> guilty. >> reporter: brother richard, owner of the van, the one who bought the cigarettes and placed himself at the store, went on trial a few weeks later. his step-daughter, amanda, was certain he'd be found guilty as well. >> it didn't make sense for them not to find him guilty because they found uncle gary guilty. and they're saying that uncle gary did it with him. >> reporter: richard was, without a doubt, heidi's last customer. and witnesses testified they'd seen a van like his at the scene. richard's van, however, showed no trace of blood or anything connected to heidi. this time the jury deliberated eight hours. and -- >> we find him not guilty.

>> reporter: two trials, two opposite results. so, here's the strange thing about the two brothers it seems, sheriff. you've got richard, who's acquitted. and yet, he is the one that says, yeah, i was in the shop. and his brother, who doesn't put himself in the shop, is the one who goes down for it. but don't they have to be in cahoots together for this to make sense? >> i would say so, but it still doesn't matter. and that's what happens with different juries. >> reporter: do you believe good arrest, good conviction? >> absolutely. >> reporter: heidi's family wasn't quite sure what to make of the two trials. heidi's first cousin is missy searles. >> it was confusing to have basically the same evidence just different jury and then you end up with two different verdicts. >> reporter: and there was something that always bothered cousin missy about the trial. the jailhouse informants testified that it was a drug deal gone bad. didn't make sense. >> she wasn't a drug user herself. she didn't participate in that.

>> reporter: clint van zandt, the fbi profiler, was also left scratching his head. his profile predicted the person responsible would be an obsessive stalker type. did you think you maybe missed something in your evaluation? >> the thibodeau brothers did not add up to my profile, so i was trying to figure out what i missed. you know, was it something that i didn't know about, that i didn't have a handle on? >> reporter: the years went by. a fading sign at the center of town was the lingering reminder that once there'd been a girl named heidi allen whose life was taken from her. >> heidi allen has been huge in everyone's mind for years. i mean, because she's never been found. >> reporter: and there was a lingering feeling in the town among some people that just maybe there was more to the story. >> i didn't know what to do. it broke my heart. it destroyed me. coming up -- a chance encounter and the shock of a lifetime.

>> he said to us, do you really want to know what happened to her? >> are we about to learn heidi's fate. >> he said, i grabbed her like this.

it was an odd conclusion to the heidi allen case. one brother convicted. the other brother, the one who admitted to being at the store, acquitted. and even though richard thibodeau was found not guilt y in some people's minds, he'd simply had a lucky day in court. step-daughter amanda. >> growing up, we were known as the kidnapper's kids. we were known as the murderer's kids. we weren't treated nicely. >> reporter: for the allen family, it was an unsatisfying result. they still didn't know what had happened to heidi. and her body had never been found. she's out there somewhere and somebody knows. >> that's right. and someday we're going to know. you can't give up hope on your missing loved one. >> reporter: even after the dust settled, the case stayed in the news for years to come. some young people like tonya priest never really forgot. >> nothing like that had ever happened in our area before.

so yeah, it stood out. >> reporter: a full decade rolled by. tonya was now in her mid-20s. one day while visiting a friend named vicki, the tv was on. up popped a story about the heidi allen case, an anniversary report. >> when the news flashed about heidi, i said to her, i wonder what happened to heidi. and she said, yeah, me too. >> reporter: it wasn't really a question, just an out-loud thought. but someone in the room decided to answer. it was the friend's boyfriend, a guy nicknamed thumper. >> he said to us, do you really want to know what happened to her? we were, like, okay, yeah. >> reporter: and this next version of that easter morning is one that needs close attention. because it didn't involve the thibodeau brothers at all, but put thumper himself and two young buddies at the epicenter of heidi's abduction. >> he said that they pulled in right up by the doors with the vehicle running. they left the back doors open. and he said, i grabbed her like this. he said, we dragged her out of the store.

and then he laughed. he said, and when we hit that van, we hit that van hard with her. >> reporter: could he be serious? i mean, is this a guy just flexing his biceps for the girls? >> no. the more we didn't believe him, the angrier he became. i said, okay, well, how did the white van get involved? he said, we just got lucky. one showed up before we did. i said, thumper, there is an innocent man in prison. he said, not my problem. >> reporter: so did she run to the police then and there? scream out to anyone who would listen? it wasn't that simple. tonya, why didn't you go to the sheriff's office at that point, say, i got a story to tell you? >> well, he lived a mile down the road from my house. >> reporter: tonya says she was paralyzed by fear of thumper. >> i went home and cried. i didn't know what to do. >> reporter: but she never forgot about that chilling conversation. she tried to cut off contact with her friend vicki and the boyfriend, and eventually tonya moved out of state. >> she was an 18-year-old girl. it broke my heart.

it destroyed me. >> reporter: the turning point came in 2010, three years later. that's when tonya learned some sickening news. in a domestic dispute, thumper had shot and killed her former friend. did you then think he was capable of having done that think to heidi? >> oh, of course. >> reporter: a domestic. >> of course. >> reporter: thumper, real name james steen, was convicted and sentenced to life in prison. tonya says that conviction and a tragedy in her own life, the death of her husband, galvanized her to finally speak up. she picked up the phone and called the county prosecutor, a guy she once knew. this is tonya from high school? >> this is tonya from high school. >> reporter: greg oakes had risen through the ranks to become oswego county district attorney, now running that same office that had gotten the gary thibodeau conviction years earlier. and, of course, he remembered the case of the missing girl. >> i was home for easter. and i remember that being on the news. >> reporter: so when

tonya priest called him with a story that implicated three new suspects in heidi allen's abduction, he listened carefully. >> i know the truth, sir. i have nothing to lose and nothing to gain from this. it's just my conscience. >> absolutely. >> reporter: the d.a. flew tonya up to new york to hear more details. and together they discussed how to verify her story, and there was one detail that seemed promising. in the story told by thumper that day, he said they'd taken heidi in the van to the home of a young woman named jennifer wescott. >> he screamed, if you don't believe me, go ask jennifer. >> what we wanted to do is try to follow up to see if there was any truth to that. >> reporter: jennifer wescott was a girl tonya knew from high school. the d.a. encouraged her to get in touch by facebook. they exchanged telephone numbers, and then it was time for a phone call. >> they plugged into my phone, taped the whole conversation. hope she'll answer. [ ringing ] >> hello?

>> reporter: it had been years since they last spoke. tonya made small talk at first. and then eased into the story she'd heard, the murder of heidi all those years ago. >> he just told me that they grabbed her from the store and they brought her to your house. >> i really in my own head dropped that. >> right. >> i don't know, probably about ten years ago. >> reporter: jennifer didn't deny a thing, but she wasn't saying much either. >> why did they even involve you or even do this? >> i don't know. >> you don't know which one killed her, though? >> no idea. >> i had to keep throwing stuff at her. and finally, she would bite. did you even know that this was heidi that they brought there and that is what they were going to do? >> huh-uh. >> had you no clue? they just showed up with her? >> yeah. they didn't even bring her in the house. they made her sit in the van. >> reporter: it sounded as though jennifer had real information. had just delivered the d.a. the evidential goods. >> it bothers me to talk about

it, i won't lie to you. >> reporter: tonya had just one more question. had jennifer ever considered going to the police? >> i would never open a can of worms like that. god almighty, i'm not doing the investigator's job. i don't get paid enough. >> at first i felt sorry for her. the more i talked to her on the phone, and the more i realized she had no remorse. >> based on the conversation that takes place, we had concerns that maybe there was some truth to tonya's claim. >> reporter: 20 years, 20 easters had come and gone since heidi's disappearance. and now with tonya's story, everything old was new again. coming up -- the d.a. starts looking into the evidence tonya helped gather. and -- >> when the investigator talked to jennifer wescott, she explained that, look, my statements to tonya priest were simply not true. >> what will that mean for the case? x of you... for when you stretch out. i want you to stay this bright blue forever...

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greg oakes had grown up not far from where heidi allen disappeared. and now as district attorney of the county, he was tentatively giving the case a fresh look. >> when somebody comes forward with a claim that potentially exonerates a convicted man, we have to take it seriously. >> reporter: inside the walls of the clinton correctional facility in dannemora, new york, we met the convict who was the subject of all this reconsideration. this is gary thibodeau, an old 61 with gimpy legs and a bad lung. did you abduct heidi allen? >> no, i did not. >> reporter: and then kill her? >> no. never abducted or killed anyone. >> reporter: he says those jailhouse snitches lied, and their testimony was the only real evidence against him. did you tell those two they're never going to find the body? >> no. >> reporter: you're not doing drugs with heidi there? >> no, no, no.

>> reporter: thibodeau has been inside for 21 years. he's always proclaimed his innocence but has long since resigned to the way life turned out for him. do you say, why me? >> i've gone through all of them feelings and emotions and thoughts over the year, but i kind of believe that you are where you are in life because that's where you're supposed to be. whether it has anything to do with innocent or guilty or -- >> reporter: but yours is more than 20 years now in the new york state correction system. >> yeah. >> reporter: for a crime you say you didn't commit. >> no, i didn't. >> reporter: back in 2013, when tonya priest stepped forward, gary had no idea the case was being given another look. he had exhausted his appeals. the other brother, richard, the one acquitted of heidi's kidnapping, says his life has been filled with anxiety. >> i've been afraid for the past 20 years actually going anywhere by myself. >> reporter: so you have really been traumatized by this whole thing? >> oh, yeah.

>> reporter: and he has also regretted coming forward as the good joe who told investigators that he'd been in the convenience store that morning. the worst mistake of your life, richard, picking up that phone? >> yeah. >> reporter: calling the cops? >> yes. they had to convict somebody. why us? because i had a van? >> reporter: are the two brothers self-pitying, saying, why me? >> they're together as like one. like, why did it happen to us? >> reporter: neither brother was aware that a woman unknown to them was banging on the authorities' doors to get thibodeau's case re-opened. prosecutor oakes was investigating, and he asked tonya's old friend, the woman on the phone who seemed to know more than she should -- >> they didn't even bring her in the house. made her sit in the van. >> reporter: to come down to the station for a talk. >> what do you know about the heidi allen case? >> i don't know anything about the heidi allen case. >> reporter: the investigator asked her about that recent phone call with tonya, omitting the fact that they had it all on tape. >> did you make reference saying that they brought her to the house and that you -- they kept her out in the van? >> no. i never said anything to her

about a van. >> reporter: well, in fact, she had. that's when they told her the call was recorded. >> oh, my god. i really don't -- i mean, i was -- this [ bleep ] lady. where does she even come up with -- what is this about? and i said, i don't know anything about them taking her in a white van. >> no, that's not what you said. >> i just thought i was shutting her up. i guess i was confessing i had heidi allen at my house. >> when the investigator talked to jennifer wescott, and she explained that, look, my statements to tonya priest simply weren't true. i was trying to get her off the phone. i was trying to appease her. >> reporter: the d.a. tracked down thumper, a.k.a. james steen, and the other two men. each said that the tonya/jennifer story was baloney. investigators also contacted the jailhouse snitches from back in the day, and they stood by their testimony. more importantly greg oakes said they got nothing for testifying. so as you reviewed them, you

found them credible? >> i did. >> reporter: why do you believe some people and not others? >> we have to look beyond just do we believe somebody or not. is there information that they can provide that can be backed up by other independent evidence? >> reporter: the d.a. didn't think he could believe anything jennifer wescott had to say, and he came to question tonya's credibility, too. >> i don't believe in tonya priest and her story. she said that had heard these admissions back in 2006. and i asked her, why didn't you immediately come forward to the police? and her response was, i simply didn't believe him. >> reporter: and after reviewing all the evidence, he decided there was no there there. >> i was convinced that they had had the right person. >> reporter: what would the motive be for these two thibodeau brothers? >> unfortunately, dennis, there has been no obvious motive for all these years. >> reporter: months had gone by since tonya first called the d.a.'s office. now she got a phone call. >> i was told that there would

be no further investigation. >> reporter: what, case closed? we've got the thibodeaus for this thing? >> yep. yep. i started crying. >> reporter: so was that it? had she given it her best shot? time to go home? well, you'd think so. >> if they think i'm going to walk away, they are mistaken. i am not. coming up -- a secret document and a stunning revelation. heidi allen was a young woman with an alternate identity. >> code name julia roberts. >> why this case might just be blown wide open. >> how did this not come out during the trial? >> when "dateline" continues. ke. unstopables in-wash scent boosters. the more you pour the more scent you'll savor. toss into your wash before your clothes for luxurious scent for up to 12 weeks. and introducing unstopables fabric conditioner by downy giving your laundry a bold, captivating scent with luxury you can feel. for long-lasting scent,

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and try olay luminous evens tone for radiant, glowing skin. tonya priest had gone to the authorities with an explosive allegation. she said a man nicknamed thumper had confessed to her that he and two buddies had abducted and murdered heidi allen back in 1994. and she was devastated when the prosecutor checked out her story and ultimately chose not to believe her. >> i was doing it because i was a good person, and that's how i felt. >> reporter: but tonya wouldn't give it up. she was convinced an innocent man, gary thibodeau, was in prison. she made calls and was eventually put in touch with a new york federal public defender named lisa peebles, someone who

had ties to the defense lawyers who'd worked on thibodeau failed appeals. >> tonya felt as though things were amiss by the time she called our office. >> reporter: lisa, the lawyer, listened to that secretly recorded phone call between tonya and her childhood pal and came away with a different take than the d.a. >> i would never open a can of worms like that. god almighty. >> that was, like, jaw dropping. >> reporter: what do you hear on that tape? >> a woman confiding it took her a long time to get the images out of her head. i heard her say they made her sit in the van. she also said that she would never go to police. >> reporter: did you believe tonya priest when she came forward? >> i absolutely did. i said, we can't let this go. >> reporter: lisa called up her friend, john o'brien, a reporter with syracuse.com. >> she says, you know, you've always told me to call you when i have a good case. and i got one. >> reporter: lisa had a morsel that intrigued the reporter. >> this was the first time in 20 years that anyone said they knew anything about what happened to heidi allen. >> reporter: one of the early doors the reporter knocked on

was richard thibodeau's, the brother who'd been accused back when but acquitted. >> oh, my god, finally. it was unbelievable. >> finally, someone's come forward to help my brother get out of prison. >> and i just said, you know, if you have anything that might help here, you know, let me know. he said, well, i do have these seven boxes of documents in my garage. >> reporter: holy cow. he's got the whole thing. >> i would absolutely like to see those right away. >> reporter: for two decades, richard had kept every scrap of paper related to his trial. was there something buried in there that the other lawyers had missed? something that might help his brother? for lisa and the reporter, eagerly digging through those boxes was like opening presents at christmas. >> and i thought, what is this stuff? the whole thing was so bizarre to me. >> reporter: there was something buried in the box, something forgotten that almost glowed it turned the out to be so important for their quest. what they fished out was an internal memo from the oswego county sheriff's office that put heidi allen in a whole new light. she wasn't just the bright-faced, smart girl selling

sunday papers. it turned out she had a secret arrangement with local law enforcement. >> heidi allen was a confidential informant. >> reporter: telling us who is selling acid on school grounds, who's dealing dope? >> right. >> reporter: she'd been issued a 3x5 informant index card. it had her name, fingerprints, even a secret squirrel informant alias. >> it had a code name, julia roberts. it had all of her personal information on this card. >> reporter: saying this woman, code named julia roberts -- >> yep. >> reporter: -- is a drug informant for the county sheriff's office? >> yes. yeah. i was thinking, how did this not come out during the trial? >> reporter: the discovery of heidi's informant status offered up whole new theories about her disappearance. >> it certainly would have opened up the field to many other possible suspects with motive to harm her. >> reporter: turns out, thumper had said as much to tonya. >> he said that that's what happens to rats. she was a rat. she was going to turn some big, big guys in and that's why they did it. >> reporter: as thumper tells it, she's a snitch.

>> she's a snitch. >> reporter: lisa peebles immediately got on with gary thibodeau's trial attorney from 1995, joe fahey. he says back when he did hear rumblings that heidi might have been working with the sheriff's office but was told there was no file, that it simply wasn't true. >> i didn't know anything about the card. i didn't know anything about julia roberts. >> reporter: so who did know? as it turns out, heidi allen's i.d. card wasn't locked away in a sheriff's filing cabinet somewhere. a deputy actually carried it around with him. and, one day, two years before she disappeared, he lost it, dropped it in the parking lot of the d&w convenience store where heidi would one day become a cashier. the i.d. was later found. it's essentially like outing an undercover officer or a protected witness. >> yes. yes. the idea that it's out there, that they believe she's an informant is a problem. >> reporter: what was important for lisa peebles about the discovery of the heidi identity card was that even though it was

in the brother's case file, it had apparently never been given to gary thibodeau's defense team. she argued that was something called a brady violation. prosecutors are required to turn over any evidence that might help the defense. lisa filed a motion to have gary's conviction throw out. and john o'brien broke news, writing the first of many heidi stories to come. >> it just took off, and people are devouring it. >> reporter: a rock had been kicked over. the reporter was now getting hundreds of tips and leads. he even tracked down one of the jailhouse informants from the trial, robert baldasaro, and recorded the interview. the man's story had changed somewhat. >> your testimony came out that he confessed to it. >> i never said he confessed to anything. i just said, you know, he never come flat out and told me that he killed anyone. >> reporter: and a co-worker of heidi's, said in a sworn statement, that shortly before heidi went missing, she'd been afraid because the sheriff's department wanted her to nail

people for dealing coke. but heidi's sister lisa was having nothing to do with the new theories. you believe that the conviction of one of those brothers explains everything? or do you think there's more to be told? >> this means that we trust our law enforcement and we trust our d.a. >> reporter: you had confidence in their professionalism then and you do now i think you're saying. >> of course we do. >> reporter: the judge looking at the new evidence decided to hold hearings. you're saying to the court there's new evidence, give him a new trial or cut him loose? >> yes. i think there has been a huge injustice and it's been a huge mistake. >> reporter: are you in a better place now? >> i feel relieved. i finally got somewhere. >> reporter: but all of the fervent interest outside the walls over the fate of gary thibodeau seemed to wash right over the man himself. can you imagine life on the outside now? >> no, no, no. i'd like to go fishing with a can of beer. yeah. that would be nice. sitting on a bank fishing, having a can of beer. coming up -- the question that provoked this

response. >> are you out of your ever-loving mind? why in god's name would we ever do something like that? why? >> and then another victim steps forward. >> he was dragging me backwards with his hand over my mouth. >> will her story reveal heidi's true killer?

in january 2015, a judge granted a hearing in the matter of gary thibodeau, the man convicted of kidnapping heidi allen in 1994. his brother, richard thibodeau, was also in the court with his family. >> i want the truth to come out. i want to know what happened. i want my uncle to be home. >> so even though i went through all this crazy crap, if he gets to go home in the end, i've done what's right. >> reporter: heidi's family was there but not expecting much. >> there's nothing new today. it's just sensationalized. >> reporter: the narrow issue at

this hearing was whether or not prosecutors years ago unfairly and illegally failed to turn over a key document to the defense. that i.d. card of sorts indicating that heidi had been recruited as a teenage sheriff's drug informant. district attorney greg oakes argued that the state had, in fact, turned over the confidential informant records before trial. >> they did receive this information. they did know about this. >> reporter: but beyond the issue of who saw what discovery evidence when was another layer. the prosecutor said it didn't really matter. >> heidi allen didn't really work as a confidential informant as you would expect. really her activity was limited to giving some high school information to the deputy. >> reporter: there was not a contemporaneous investigation about to go down? >> around the time of her disappearance, no investigation that she was involved with. >> reporter: so if heidi wasn't naming names and turning in drug dealers, then the prosecution argued there was no foundation

to this new theory that bad guys had killed her in revenge for being a snitch. the now-sheriff vehemently denies the defense innuendo that the deputies were somehow responsible for getting heidi killed. did you guys carelessly bust her identity, sheriff? >> are you out of your ever-loving mind? why in god's name would we ever do something like that and jeopardize a girl's life or career or anything? why? >> reporter: accidentally. you know, this resulted in a girl being vulnerable. >> how did she become vulnerable? >> reporter: the sheriff says, yes, her i.d. card was dropped in a parking lot but was returned to the office right away. only the store owner saw it. but something else was going on in the hear. lisa, the defense attorney, was also acting a little like a prosecutor. she was about to introduce evidence about those three men identified as the so-called abductors and killers. >> all i have to do is say, hey, there is this new evidence and

had it been available, it would have created reasonable doubt for a jury to acquit him. >> reporter: he called other witnesses who, like tonya had heard stories of these three men killing heidi and disposing of her body. >> he said he would do us like that girl. >> reporter: and that girl from the phone call, jennifer wescott, she changed her story again. telling authorities on tape that she did know what happened. >> all he said to me was heidi was burned in a wood stove and taken care of in a van. >> reporter: and then the men themselves. first, there was thumper, real name james steen, doing life for murder. >> i have nothing i can tell you ma'am, that will save that man over there. nothing. >> reporter: he claimed not to know about heidi's abduction nor did potential suspect number two, his buddy roger breckinridge, another guy with a record. and then there was the third guy from tonya's story. his name was michael bohrer. he lived a mile from the convenience store and had heidi make him a sandwich most days she was working.

what made bohrer stand out among the three was his admitted obsession with the heidi allen case. had told investigators as much months earlier. >> i knew one day i'm going to pop in the picture somewhere. >> you seemed so preoccupied with the case. >> i was obsessed with it because it just freaked me out. >> reporter: turns out, he had a shoe box full of old news clippings he'd kept for two decades. in court, bohrer's testimony was was videoed, but he admitted years back he'd been a drug dealer, and he became very emotional. >> he started crying when it came to questions concerning his obsession with the case. and he kept driving by the sign that says, where's heidi. and he thought about her six times a day. >> reporter: strange. and remember that profile drawn up by the fbi agent, clint van zandt, today a contributor to msnbc? back then he'd predicted heidi was killed by someone who would

later appear to be obsessed with the case. >> it's going to be someone who knew the victim. it's somebody who will follow this crime very closely, who will gather newspaper clippings, articles. >> reporter: and there was something else the fbi profiler had predicted. >> what i suggested was, this is so bold, they're going to have other type of offenses in their background. you may see stalking, you may see other type of kidnappings. >> holy cow. he just profiled michael bohrer. >> reporter: the attorney tracked down this woman, catherine schmitt, who says she was attacked by bohrer years before heidi's abduction. she told us he tried to push her into a car. >> had me in a chokehold and was dragging me backwards with his hand over my mouth. and, i mean, i couldn't breathe. >> reporter: she managed to run away with minor injuries. bohrer pleaded guilty to unlawful imprisonment. but the judge wouldn't allow catherine schmitt to testify at this hearing, ruling her story about michael bohrer was not relevant. >> he is absolutely very curious. i think he's mentally unstable. >> reporter: or he knows what happened to heidi and he feels

remorse all these years later. >> i don't believe that's the case. >> reporter: so the judge took it all under consideration, dismissed the hearing and said he'd have a ruling in due time on whether thibodeau should get a new trial. weeks went by, then months. >> it's given me a reason to live now. >> reporter: and when it finally came, the ruling was dropped with little fanfare, just an entry in the docket. the judge ruled first there had been no so-called brady violation, no proof that the state did not hand over documents related to heidi's drug informant status. and he agreed with the d.a. that it wasn't legally relevant anyway. >> it's all speculation. it's irrelevant. it's hearsay. >> reporter: and as for those alternative suspects put on by the defense? interesting, but in his opinion too speculative and remote to warrant overturning the jury's verdict. none of the three has been charged with anything related to the heidi allen case. >> i can't let it go. and i won't let it go.

>> reporter: lisa peebles and, most of all, gary thibodeau and his family, lost that day. >> as long as gary's alive, i'm just going to keep on fighting for him. >> reporter: in fact, a high other court has agreed to consider an appeal. and as for tonya? >> what do you do? you just keep fighting. >> reporter: oddly maybe, those two families, the thibodeaus and the allens, divided as to guilt and innocence, both all these years later have the same question -- what did happen to heidi, and will we ever find a shallow grave? >> i think, eventually. >> eventually something's going to happen. someone's going to say something. >> i might not know on this side of heaven. i might have to wait. but i will die trying and fighting for her. >> reporter: she went to work early on an easter sunday morning and was never seen again. that's all for this edition

for now. i'm lester holt. thanks for joining us. one day away from perhaps the most watched debate in american history. >> i'm going to be very respectful of her. >> you have to be prepared for wacky stuff that comes at you. >> will they about the moment that determines who will become the next president? donald trump adviser general mike flynn and the hillary clinton chairman both join me live. plus debate prep school. one moment can change everything. >> i can't. the third one i can't. sorry. oops. >> how the presidential candidates plan to knock their opponents off stride. i will talk to two former campaign managers who have been inside the war room before. also, how does a man who says this about donald trump -- >> this man is a pathological

liar. he's a bully. a narcissist at a level this kae country hasn't seen. >> what's behind his change of heart? >> two police shootings this week. >> don't shoot him. >> peaceful protests are growing around the country as we grapple with the question, what can be done to keep this from happening? joining me for insight and analysis are doris kearns goodwin, hugh hewill, gwef ifil and mike murphy. welcome to sunday. it's "meet the press." good sunday morning. it's an nfl sunday. really, this feels like a pregame show. the big game is tomorrow night on new york's long island. with a super bowl size audience expected. usually the first debate is the most important campaign moment until the next debate.

probably not this time. hillary clinton comes in with nervous democrats feelin a little bit better about things. four national polls showed clinton up. three of the polls she's up by six points. in today's washington post/abc po poll she's up by two. some show donald trump doing better and have a path. trump has never been more competitive than he is now. there's a sense if clinton doesn't knock him out tomorrow, she may never be able to before november. both sides are engaging in psychological gamesmanship. the clinton campaign has placed mark cuban, a huge trump critic, up front in the audience as a way to rattle trump. in response, as hard as this is to believe, trump has invited gennifer flowers to sit in the front who had an affair with bill clinton in the '80s. one thing we know for