thanks for joining us. i have some exciting news. her husband, a decorated military officer, shot in the dark of night. >> it was an execution. >> was this some sort of hit? >> he was in special forces. there must have been something at work. >> that's what police thought too. until they learned about the secret life of this husband and wife. >> they would meet couples on the internet. >> was there a forbidden affair? >> they were probably meeting for sex about four times a week. >> and did it lead to murder?

>> she is absolutely cold-blooded. >> soon, there would be questions for mother and daughter. >> it was another shock. >> "the mystery of the murdered major." hello and welcome "dateline extra." i'm craig melvin. like so many others, this story involves a husband and wife. he was a military man, a respected major in the u.s. army, when he was attacked in the middle of the night, police launched an investigation that would reveal eyebrow raising secrets, secrets that might hold the key to murder. here is keith morrison. >> the wind in the northern prairie sweeps across a vast flatland. grave markers around a military ceremony. the final resting spot for a few dozen veterans, many of whom died in combat.

this is where he is resting now. major david shannon, who lost his life in 2002. his mother shirley comes here to visit and remember. his sister brenda too when she's in town. oh, how they worried that war might put him here. except war didn't. no, there never was a thought back then about what could

happen far from combat, what did happen. all those strange things down south in north carolina. fayetteville is an old town, steeped in revolutionary and civil war history. smack in the middle of the bible belt. but now, cargo planes buzz in and out of pope air force base. all past the confines of the city sprawls the immense ft. bragg, home of david shannon. his house was here, a few blocks off-base. the major, his wife joan, and their four children. it was july, 2002. like a sauna that night, so hot and humid. and then a light rain that cooled it down again. david and joan watched a movie on tv, fell asleep. and then -- >> i don't even remember hearing the first shot. i remember something woke me up. >> and then you heard a shot?

>> and i know whatever woke me up, i know my ears were already ringing. and i turned the light on. and i see that he's shot. you know, it shocks you. never, ever forget that image. that's burned in my brain forever, no matter how much i

try to -- here is the person i love. he's dying. [ sirens ] >> and by the time the police and the ambulance wailed up to the door, it was too late. david shannon, just 40, was dead. all it took was a look, in fact, for lead detective mike murphy to see what happened in david's bedroom was highly intentional.

>> it was an execution. the intruder came in while he was sleeping, placed a gun to his head, and shot him in the chest. >> and joan? the shock of it didn't help, of course, nor the fact that she was sound asleep when it happened. by the time she calmed down enough to talk to police, she wasn't very helpful. >> i did not clearly see the person who shot david. i'm not sure if i saw or just had a feeling of somebody just leaving the room.

but -- i thought it was a shadow. >> did you actually see a shadow or did you tell the police you thought it was a shadow? >> it was a movement, like a shadow that left. >> she was worried about the safety of the children. she returned back to her bedroom. that's where she made the 911 call. >> the children. joan and david's eldest daughter daisy was out of town. but their two young boys, just 7 and 10, slept through it all, unaware of what happened. down the hall was shannon's 15-year-old daughter elizabeth, who told the cops she was also in bed, and spending the night with liz was her best friend vera thompson, also just 15. >> both their statements were similar. they were listening to music, watching tv, and they fell asleep. >> five people in the house, and not a one saw or heard a useful thing to help determine who committed this horrible crime, or why. and there weren't many clues either, at least not in plain sight. but that wasn't necessarily because the killer covered his tracks. >> the home was cluttered. there was filth, clothes all over the floor.

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the only thing that was perfectly clear was that somebody wanted this man dead, wanted it badly. shot him in the head and the chest while he slept. his wife joan sleeping soundly, then startled away beside him. >> she had seen the shadow of a

person, just subscribed the subject as a male subject. >> just like that, in a split second, the kids lost a father. and their life together over their 11-year marriage was over. >> david and i had a good marriage. if he were alive, he would say, we had a good marriage. i do miss him. i miss what we had. there's not anybody that would ever be able to replace him. >> the murder of an army major was big news in fayetteville, especially an officer working in special ops. but truth be told, murders happen.

fayetteville gets its share. david shannon would be missed, all right. but not just here. oh, no. murder is rarely strictly a local event. its waves are felt all over. and news of this one skipped upcountry and crossed the windy prairie to a place called langdon, north dakota. that's where the major was from. this is where he grew up, where he became an unusual young man. >> he was quiet. he wasn't one that was dating. he didn't have a lot of friends. >> brenda strong is david's older sister. >> he wasn't into sports. he just was introspective. >> but his mother shirley says david always knew exactly what he wanted to do. >> i am going to be an army man. that's what he said. >> how old was he when he first started saying that? >> maybe 6, 7 years old. >> by 19, david had enlisted. he was eventually stationed in upstate new york. and that's where he met joan. >> he was funny. he had a sense of humor. he was extremely shy. >> david was different than the other guys how? >> oh, because he treated me a lot different. he treated me like i had value. >> which was something wonderful and new for joan. sexually abused at 12, abandoned

by her parents, married to an abusive husband, had a baby with him at 18, another one in short order, and soon single again, working in a topless club, hooking up with the wrong kind of man. and then she met her knight, her savior. she met david. so before the men had wanted you for sex but that was it. this guy wanted you for you. >> he was willing to protect without controlling. he treated me like an equal. >> less than a year later, joan asked david to marry her. >> i realized he was this really, really great guy. i didn't want anybody else to have a chance to find that out.

>> so in a small north dakota church, joan taft became mrs. david shannon. >> i thought he found somebody that was good for him. he was obviously happy. >> and she, what was your impression of her? >> she just seemed very nice, very sweet, very attendedtive to him, very much in love. >> they complemented each other, is what they did. >> it sounds almost as if you're

talking about jonas if she was one of your children. >> she was almost like a daughter to me, yes. >> as for joan's two young daughters, daisy and elizabeth, david wanted them to be part of his new family. >> because he loved me, he loved them. >> and so he did. david shannon became both a husband and a father. >> they were all having a good time being a normal family, you know. everybody getting along, fighting, as you do. he loved them, definitely. >> soon the shannons became six, with the birth of their two boys. and in 2000, david took the family south to fayetteville, when he was transferred to ft.

bragg. >> david loved the military. he loved being the soldier. you talk about somebody having a first love or something they loved more than anything. he loved that uniform. >> and the military had been good to david. he was major shannon by now, well on his way to becoming a colonel. and that was the phone call the shannon family was really looking forward to from ft. bragg. not the one they got that devastating morning in july 2002. >> they said david's been shot. he's been murdered. it couldn't be, he was in special forces, he must have been into something odd, there must have been something with what he was doing at work that, you know, this must have been a hit. >> execution style, somebody came in with the intent of killing him. >> with the intent of killing him. >> what she was telling us didn't really -- it just didn't really match up at the time. >> and something else that didn't seem to match? stashed away in the bedroom were dozens and dozens of pornographic magazines and videos and sex toys. joan gave investigators a completely unexpected and surprising answer. >> i told them that david and i were swingers. >> and suddenly the investigation turned on its heel and headed in a whole new direction. >> they would meet couples on the internet. and her husband would prearrange it, then they would engage in some type of sexual relation with the couple itself. >> did that make your invective mind click? >> the person who shod david shannon might be familiar with joan shannon. maybe the swinger lifestyle might have had something to do with that. coming up, an intriguing new lead. was there a fatal love triangle in this circle of swingers? when "the mystery of the

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while investigating the murder of major david shannon, police discovered the seemingly straitlaced military officer and his wife had a complicated love life. did it lead to his murder? here again, keith morrison.

>> they seemed from the outside, at least, ordinary, exemplary. a good marriage, four attractive kids. but murder investigations have a way of shattering what seems to be. and now the shannon family secrets were spilling out. of course you can have no idea what might exist behind the photo of family values. that's what detectives are for, after all. the shannons may have moved to the bible belt, here to fayetteville, north carolina. lots of churches here. but there are also other activities that occurred at night that had nothing whatever to do with family values. joan and david shannon were swingers. enthusiastic members of clubs whose sole purpose is to organize various combinations of

spouse swapping. as joan told the police, she and david had been swinging for years, long before moving to north carolina. fayetteville, after dark, to their happy surprise, offered plenty of fresh opportunities to continue their lifestyle, as it's called. david discovered that, said joan. >> we get here, he gets on the computer, and he finds the location of a club. >> right off the bat? >> sure did, yes. >> who knew? it was as if this conservative bible belt state somehow needed secret outlets for its more lurid desires.

>> he would go on the internet. there were a lot of swinger sites. david would look for people on these swinger websites. >> the swingers' club david found was one of many in fayetteville. and this particular one catered

to both couples and singles. and how did that affect your marriage? >> i think it improved it. because, you know, so many marriages fall apart because somebody cheats. but it's not the sex. it's the betrayal, the lies. i don't associate sex and love together. >> in fact you both liked it a lot.

>> we did. we did. >> the shannons often met couples at hotels. sometimes they even brought them home. always trying to be discreet, of

course, so their four children wouldn't find out. they would often find themselves hustled off to a friend's for the weekend and come home to find their bedroom rearranged. their daughters had an idea that something was going on in their absence. but murdered exposes secrets, as they say. ♪ he holds your house in the palm of his hand ♪ ♪ he's your home and auto man ♪ big jim, he's got you covered ♪ ♪ great big jim, there ain't no other ♪ -so, this is covered, right? -yes, ma'am. take care of it for you right now. giddyup! hi! this is jamie. we need some help.

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welcome back to "dateline extra." in the case of the murdered major, one thing became abundantly clear. nothing was as it seemed in the shannon household. for starters, the army major's wife and mother of four was in a sexual relationship with a married man. once again, keith morrison. >> it was quite an eye opener. that is, which joan shannon told detectives that she and her now dead husband, major david shannon, were regular and enthusiastic swingers. but when joan told them she developed a special one on one thing with a married man named jeffrey wilson, now that was a real lead.

could it be the major was the victim of a jealous lover? so detective murphy paid a call on wilson, also a soldier here at ft. bragg. >> jeffrey did confirm he was involved in a romantic relationship with joan shannon. >> where was he when this murder occurred? >> he was actually working at the time of the homicide. >> in fact, a little checking revealed it was an unassailable alibi. jeffrey wilson was innocent. of murder, that is. he was very cooperative. he revealed every lurid detail. >> back in april, they were probably meeting for sex about two times a week. and in july, and of course the murder occurred on july 23rd, at least four times a week. >> so now the deputy d.a. began to flip the idea of a love triangle motivate on its head. it seemed to west the person who had reason to kill david was not

jeffrey, but joan. >> from jeffrey's point of view, he describes how she was in love with him, that she was not in love with her husband, that she didn't want to be with her husband, that she financially could not afford to leave her husband. >> wilson said he kept telling her he was only in it for the sex, didn't want to run off with her. but if secret sex was all he wanted, joan, he said, kept pushing for more. >> and the situation actually continued to escalate. i think it was around july 18th. again, that would have been five days before the murder. jeffrey describes how he talks to joan and joan says, i can't

take this anymore, i want to be with you, can't we just run off together? >> david shannon knew, of course, that joan was seeing jeffrey wilson. after all, he invited jeffrey to join them in the first place. but maybe he wasn't so happy about the cozy friendship joan seemed to be developing. that broke the rules.

>> david told joan that she could no longer see jeffrey because he could see that joan and jeffrey had become romantically involved. and i believe it would have been sunday, she's actually having sex with jeffrey wilson, and actually david is killed in the early morning hours of tuesday. >> if you ask joan, and of course we did, wilson just didn't understand. didn't understand that the affair was actually winding down. why would he say you were in love with him then? >> he's a very self-centered and into himself and believes the whole world loves him. i didn't. we were actually pulling apart. it was coming to the end. >> really? detectives added it up and here's what they had. a story of some shadowy intruder that didn't seem to check out. the swinging, the affair.

the story, true or not, that she wanted out of the marriage. and by the way, she stood to collect $700,000 in insurance money. the detective confronted joan. and she? well, given her lifestyle, she said, she wasn't surprised at his attitude. >> he's disgusted. he's automatically prejudiced against him. he's focused on it, determined he's going to get me. >> in north dakota, david shannon's family tried to keep up with the shocking information. the murder, the revelations about swinging, and now joan was telling them that she had become a suspect, to which they replied -- joan? not a chance. >> we tried to play the scenario. did joan have a part in it? none of us could see that she could possibly have done that. it is just not in her nature to do that. she can't. >> but brenda did have somebody else in mind. >> now, elizabeth?

i could see it. >> elizabeth? the shannons' 15-year-old daughter? is it possible she was a cold-blooded killer who executed her very own stepfather? the man who adopted her, raised her, provided for her? maybe, said david's sister brenda. daisy and elizabeth were always troubled, said brenda. and when elizabeth hit her teens, watch out. >> david and joan did not have the tools needed to deal with what those two girls dished out. it was boys, drugs, violence. if she got angry, she would destroy something of theirs.

>> that was hardly elizabeth's view of things. she conceded she was no angel. she acted out all right, never denied that. but elizabeth always claimed it was the adults who made it ugly and hostile at home, where arguments and not affection were the family routine. joan now says she realizes she was manipulated by her daughter. >> i gave up. i hate to admit it. i gave up on that child. i didn't know what to do. >> joan turned the task of parenting elizabeth over to major david, the military man, who did what he could to keep military order. >> he was definitely the tough one. he was the one that would decide the punishment, how long the grounding was going to be. >> a war of wills. david would ground her. elizabeth would escape. david responded with locks and alarms on her bedroom doors and windows. she squirted out anyway. nothing seemed to work. >> what can you do, if you can't keep your kids at home? you can't chain them. >> clear message to david. you cannot control me no matter what you do. >> that's right. >> in fact just a couple of weeks before he was murdered, david called home to north dakota to vent, ask his mother for advice for dealing with that girl. >> i did ask him, i said, would she do something? >> do something, what did you mean, would she do something? >> do something violent, yes. he says, i don't think so. >> but you asked the question for a reason. >> i did ask him, yes. because i did not trust her. coming up, someone from inside the house that night steps forward.

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returning to our story once again, keith morrison. >> murder. that most abhorrent of crimes is shocking enough. but in the days after major david shannon's sudden passing, the shocks resumed, as disturbing suspicions began to

circulate and grow. by the time they laid the major in the ground, the question of who did this dreadful thing seemed to be heading toward an early answer. it was elizabeth. david's family was convinced that rebellious elizabeth was so full of hate, she actually shot and killed her own stepfather. an opinion supported by several anonymous calls to the fayetteville pd. >> we had crimestoppers tips coming in, saying that elizabeth shannon was actually bragging about the homicide.

vera thompson was telling people about the homicide, that elizabeth shannon might be involved. >> vera thompson, remember her? she was elizabeth's best friend who was staying at the house the night of the murder. police brought her in again for questioning. and this time they grilled her. >> she was extremely emotional. she didn't want to tell on anybody. at that point in time she began to lay the facts on the table. >> and oh, what facts they were. vera was elizabeth's buddy, her bff. they talked about everything, went everywhere together. >> when she started bringing up facts, we were able to

corroborate some of the information. >> vera provided plenty of supporting details. how just days before the shooting, she went with elizabeth to a field and test fired the murder weapon. cops later found matching shells there. and how elizabeth dumped the gun that night with a guy from the neighborhood named dee humphrey who was waiting near the house. humphrey was interviewed. he admitted it was true. vera's story added up. >> so everything was believable. >> then vera, just 15 years old, naive, frightened, no attorney representing her, dropped her bombshell. >> vera eventually became aware of, through elizabeth, that joan and elizabeth had had some discussions about killing david shannon, that her mother had attempted to poison david shannon, that joan shannon and

elizabeth shannon had conspired to kill david shannon and it actually was elizabeth that had shot him that night. >> a conspiracy? joan the brains, and elizabeth the brawn? given the tumultuous relationship between mother and daughter, who could have imagined they could agree on anything, let alone murder? but, said vera, that's the story elizabeth told her. and it implicated both her best friend and joan shannon in a homicide. >> the arrest warrants went out for both of them simultaneously. joan shannon was arrested actually before elizabeth was arrested and before elizabeth gave any statement in the case. >> david shannon's family was in fayetteville for david's funeral. right there with joan when the cops came, saw what they did. joan had been practically paralyzed with grief, they said. and then arrested. >> they put cuffs on her. i imagine they read her her rights right then. but i don't know. it was another shock. >> joan herself was unshakeable

in her insistence she did not do it. she had no part, she swore, in any of it. >> i might not be clear on that night. there's a lot i can't be clear on. but i know i didn't kill him. i know i didn't give elizabeth the gun. i know i didn't try to poison him. and i know i didn't try to get anybody to kill him. >> although, to the police, on the day of her arrest, she said nothing at all. on the advice of paul herzog, the lawyer appointed to represent her, in the battle of her life. attorney on the case, joan's loyal in-laws began to relax. >> once they finally started finding real evidence, they would know it was not joan. >> they would eliminate her? >> right. they would eliminate her. mm-hmm. >> especially once the police arrested elizabeth. but there was a little problem. elizabeth had quite suddenly disappeared. coming up, the hunt for elizabeth begins. where was she? and would anyone believe her story? st one real beef chew givn once a month, every month, helps keep your dog safe all year long. test dogs for infection prior to use. in rare cases digestive and neurological side effects have been reported. for more information contact your vet. get your dog out of hiding. ask your vet about heartgard plus. the vet's # 1 choice

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>> on the outskirts of fayetteville, north carolina, is a mobile park. quiet, wooded, secluded. and in the summer of 2002, it had a new resident. elizabeth shannon was holed up in a trailer here hiding. >> we received a call saying that she was at such and such location. when we entered the home, we found her hiding, you know, underneath a futon in the living

room. >> they arrested her, took her downtown, read her miranda rights and then questioned her without an attorney. at the time elizabeth, remember, was just barely 15 years old. and what did she say after two hours in that room? >> i told the story. >> the whole story? >> uh-huh. >> elizabeth confessed it all. every grisly detail of that awful night in the shannon house. assuming, that is, that what she told the detectives was actually true. >> it got to the point where i finally did for her. but it never would have happened

without her. >> her. her very own mother joan shannon. she insisted her mom had wanted david dead for months. first by trying to poison him. then later recruiting one of liz's friends to kill him. and finally -- >> she was like, would you be brave enough to do this? >> to do what? >> she wanted me to kill my step dad. >> in 25 years on the job, detective murphy had never heard a story quite like this. he pressed further, he said, pushing elizabeth to explain how her mother talked her into murder. and the answer, elizabeth says now, was this. it was love given and withheld. >> it wasn't an affectionate home overall. i wanted, like, a real mother/daughter relationship and it was never really there. >> prior to it, they were going out being a family.

there was some type of parental involvement. >> and she liked that a lot. >> she liked it. that was something she was lacking. >> but having finally offered her daughter the maternal affection she so craved? joan threatened to withdraw it unless she got that gun and used it to kill her father, or so elizabeth claimed. >> sounds crazy at first, but when somebody is in your year let alone your mother every day, it got to the point it was just normal. i just want to do this so nothing changes between me and her. >> and so elizabeth said on that night she took one of her stepfather's many guns, arranged ahead of time for a way to get rid of it, and waited while her parents watched their movie and fell asleep. >> she walked into the bedroom, placed the gun over her father's head, squeezed the trigger. then she placed the gun to the chest and she fired the second round. >> as far as prosecutor billy west was concerned, elizabeth's tale had the ring of truth. >> i think she did it at the behest of her mother and in some respects to please her mother. >> so in exchange for her testimony, the da offered liz a deal. instead of life without parole, she could plead guilty and get a sentence of 25 to 31 years. >> we felt that was appropriate. offered joan the same plea deal that elizabeth had been offered. so that offer was extended by the state.

>> no, i wasn't going to do it. >> why not? >> because when you're innocent, you're not going to say you d >> so it didn't sound surprising that liz would try to set up her mom like that. because as a child, if there was trouble, liz was usually there. but she always had to share the blame. >> she blamed somebody else? >> oh, yeah. >> even if she was caught red handed? >> absolutely. elizabeth always shared the blame. >> so now joan shannon's fate would be decided by a jury. da billy west told them about joan and david's swinging lifestyle. joan's affair. jeffrey wilson's claim she wanted to run away with him financed with insurance money from david's death. then there was the allegation that joan tried to poison david. and testimony from a young man who insisted joan asked elizabeth to recruit him to commit the murder and dispose of

the gun. but the da saved his star witness for last. 15-year-old elizabeth shannon herself who told the jury that joan used a truly devious weapon. maternal love given and withdrawn to manipulate her into murder. >> i can take responsibility for my role in everything. but she was trying to put everything on me. that's the point i kind of woke up and realized, like, let me just tell the truth. >> was it true? on the stand elizabeth's accusation was clear and powerful. >> throughout the whole thing while i was testifying, she couldn't even look at me. >> joan did not testify. she sat quietly and listened as

her attorney portrayed liz as a liar and ruthless killer who acted entirely alone when she executed her stepfather. >> she is absolutely cold-blooded. she is entirely self-interested. >> elizabeth? >> she hated joan. she hated her parents. she wanted out. freedom. she would have done anything. when she killed david, she killed the only disciplinary she'd ever had. then she made a deal to get herself out of it. >> the idea that joan manipulated elizabeth wasn't even possible, said the defense. certainly not for either of her parents.

>> they couldn't keep her in school. they couldn't keep her in the house. they couldn't get her to do anything. then all of a sudden joan's going to get her to turn around and kill david? >> the jury deliberated a day and a half. then -- >> they came back guilty. >> my heart dropped. you go numb. it's like, so many things flash through your mind and you just realize life as you know it is gone. >> it was so unbelievable. we knew joan was innocent and she'd just been found guilty. it shattered our world in so many ways. >> joan shannon will spend the rest of her life in prison for orchestrating the murder. she has no chance of parole. no more appeals. and elizabeth who actually pulled the trigger? she, too, was sent to prison for at least 25 years courtesy of the deal she cut with the da. >> i told the truth from day one. i wouldn't gain anything by lying. i would just sabotage my own life in the process. it doesn't make sense. >> they are in separate prisons now. two hours apart by car. but really a world away. we asked if they wanted to speak to each other, make peace,

perhaps. look at our camera, we suggested. speak from the heart. >> i still love -- i still love you, elizabeth. it's very complicated. it's very difficult. you're still my daughter. and i know the situation is hard for both of us. and i am sorry i wasn't a better mother. i can't go back and change that. >> but elizabeth didn't like this idea. >> i don't have anything to say to her. because it doesn't matter what i say. it's like she's not going to change. she's not going to tell all these people that she lied. >> in the years following their father's death, joan shannon's two sons, david's sons, were living in north dakota and grew up in the major's boyhood home here. his mother became in joan's absence their mother and grandmother. the boys believed in joan's innocence, visited her sometimes, and talked to her on the phone. they were not speaking to their sister. and major david shannon, his remains will spend eternity here

just down the road from home in the old military graveyard under the black prairie sod and the wind. >> that's all for this edition of "dateline extra." i'm craig melvin. thanks for watching. i'm craig melvin. >> i'm natalie morales. >> this is "dateline." >> she was a college student found on a lonely road in texas. >> we figured that she had been sexually assaulted. >> tough questions for her boyfriend. >> where was i the night before. when i had last seen her? >> i really thought he could be our killer. >> why police tried to prove it, another attack. >> he got me by the throat and shaking me and telling me not to say a word. >> you're a prisone