we're going to be roping this whole area off. >> i saw her two weeks ago, and she was fine. >> nicky's body -- >> a mother found dead, covered by leaves. no clues, no evidence. just a little square of video. smoke a late night cigarette on the porch, the last time she was seen alive. >> i said, are you serious? call the police. >> tonight, "20/20" takes you inside that family's nightmare. their home mysteriously hot wired with 21 surveillance cameras. rolling nonstop, recording everything. >> can i help you? >> her husband, a security expert, trying out the latest equipment on his very own family. >> he was trying to watch the

entire world around him. >> but is his wife just being mad. >> no, no, no, no, no. i know for a fact i let it go. >> or go mad? >> my wife has a long history of mental imbalances. >> she was a train wreck waiting to happen. >> this is really freaking me out. >> the pa media, obsessed. >> this woman was murdered. >> and two days of crucial tape missing. >> here's a man waiting for a crime to happen every day, and one finally happens. he has no pictures of it. >> what happens after an autopsy on the computer? >> it was bold. >> tonight, haunted by the case . >> i made a promise to myself, i would never give up. >> the suspect's daughter defending him, taking their crusad crusade public on youtube. >> my father is telling the truth. >> and how it gets stalled by a voice from the grave. >> i don't want any part of this freaking family anymore.

>> what the camera didn't see. good evening. i'm elizabeth vargas. welcome to "20/20" saturday. >> i'm david muir. right here tonight, is the case of a father trying to protect his family, or simply wanting to watch their every move 24/ 7. that verdict is now being appealed. here's what we want to know. what do you think? is a new trial warranted? >> crucial evidence centered on those recordings taken from a command center right inside the home. thousands of recordings that took investigators a year and a half to review, but where are the missing tapes? could they solve everything? here's jim avila. >> reporter: what would we see if your home was being watched inside and out 24 hours a day by 21 surveillance cameras? watching as you sat on the couch in front of the tv, unblinking as you sneak outside for a smoke on the porch. >> show me where you saw cameras. >> if you see the front door to

the right of it, basically, up in the corner, there was a camera up there. from the top, on the back corner of the house. >> reporter: welcome to sydney's cove. a quiet called sack in lawrenceville, georgia. bells of the baptist church can be hard in the backyard. and dinner time is marked by the rumble of the freight train. it's home to matt and nikky lively, and their children. why all the cameras? matt's in the business. he sells security systems, a tech savvy law and order guy when has become a one-man neighborhood watch. we sat down with her family. her father, her daughter and sister, amy. >> i knew that there were cameras all over the place, because i mean, he made it a point to sort of brag about it really. it was sort of a source of pride

for him. >> reporter: the house seems so tranquil on the outside. matt and nikknikky, both 44 yea old, married on valentine's day, together 14 years. she was southern, an account, the bread winner. matt, a new yorker, called her baby cakes. >> nikky told me that she was in love with him. >> their daughters now teenagers, posted this youtube video of the trip to hawaii to frolic in the sun. >> my mom surprised by dad while they were down there, and renewed their vows. she is happy, they were in love. >> it does sound like people in love, and care for each other do. >> reporter: but just like hawaii's famous volcanos, this love affair is about to blow in the dark of night, and thanks to matt's over the top obsession, we hear it all.

>> before i breaking this [ bleep ] office. i'm going to start breaking this. >> i know you are. i know you are. >> reporter: that steel magnolia plus size voice belongs to nikky, 93 pounds soaking wet. matt is a giant oaf of a man. big enough to lift his tiny wife with one hand. on some of the recordings, he he sounds like a punching bag. i can't keep doing this. >> you're un[ bleep ] believable. how you can talk to me -- >> lower your voice. lower your voice. >> how i spend my time. >> reporter: the reasons for their fights might sound familiar. money and sex. they are $300,000 in debt. their love life, troubled. they are see a counselor. >> pick it up. >> i'm saving this manrriage.

>> the problem that you want is not me, and not us. >> reporter: matt's surveillance business has become his obsession. watching, always watching. the porch cams, the yard cams. the driveway cams. all diligently documenting the non-events of daily life. >> he has the systems the military would be jealous of. we're talking about a huge server bigger than what we would have at the police station. >> reporter: alex moved out at 16 because she couldn't get along with her dad, and she left her half-sisters behind. >> it was uncomfortable. he had a camera in the living room, and you were being monitored. but matt insists there was a reason for all that surveillance. he was worried his wife had become mentally unstable. >> i'm going to protect my child, and make sure you're not a raving lunatic first. >> you don't need to protect

them from me. >> reporter: worse, she had a habit of storming off. >> get the blk [ bleep ] out of my way. >> can we compromise here? >> well, i propose you calm down for a moment. if in a clear head, you want to leave, i'm not going to stop you. >> good. >> reporter: now matt's afraid nikky might run off in a rage and get hurt. to deal with that, he turns to another of his tech skills. hidden audio recorders. in her purse, in her car, and using her cell phone to track her. here's matt's explanation. >> i'm recording my wife and i have a tracker on her, you know? i have to find my wife every time she runs away. aye not some over-possessive freak. >> reporter: the girls still living in the house are witness to the constant marital battles. in that youtube video which will play a big role later, they say their mom was the problem.

she was acting crazy. >> she was saying how she was tired of the voices telling her that people were talking bad about her, and she was tired of the voices telling her this, and the voices telling her that. >> reporter: that was june 28, 2011. nikky calls 911. documentation of what matt says he fears. she is running away from home, and he is trying to stop her. >> my husband refuses to let me leave the house. >> my wife is yelling and screaming me, and just woke up the children. doesn't the cops here? i think my wife is throw a tantrum. >> let me have her tell me that. >> pick up the phone, or else they will come. >> you don't need to comp. >> i have them dispatched. >> thank you, ma'am. >> you're welcome. >> reporter: the cops come by to make sure things are under control, but nikky doesn't even look at the officers. that's her bag, packed and ready by her side.

later that day, she takes it and leaves. and within hours, matt has her then 12-year-old daughter, amanda, call and beg her not to stay away. it's haeartbreaking. >> hey, mommy. >> how are you? >> good. mommy, we need to go on vacation. all of us as a family. we need to save this family. >> reporter: the family doesn't go on vacation. nikky comes home. they stay at sydney's cove behind closed doors with those cameras rolling. things seem to be getting back to normal. the family saved for two weeks until a july night, that small figure on the screen is nikky. it's date night with matt. dinner and a movie. and later that night, the lily's surveillance camp show a smoke before bed. we can't tell, but this cigarette is not the only thing smoldering that summer night. nikky is about to disappear.

when we come back -- after 13 years of marriage and thousands of arguments, nikky is finally gone for good. and her husband says it's because she is crazy. where is nikky, and what do all those cameras say about her disappearance? st

>> announcer: "20/20" saturday continues with what the cam are didn't see. >> reporter: a hard-working spit fire of a woman, nikky lily, mother, bread winner, a whom who despite her size, takes nothing from her outsized husband. now she is missing. nowhere to be found in her family's upscale house outside atlanta. we can go inside with video obtained by abc news. any clues that answer the question, where is nikky? go ahead. look around. see any signs of a violent struggle? bloodstains on the carpet? broken furniture? there's a gun in a holster, but it's not smoking. nothing more incriminating that an unmade bed, and there's the

fortress. yet someone so concerned with the comings and goings in and around his house, matt waits two days before bothering to pick up the phone and call her sister, amy. >> he said, have you talked to nikky? i said, no. why? what's going on? he said, she is missing. i said, are you serious? call the police. >> reporter: after that call, matt did file a missing person report and told his story to police. he and nikky had a fight. he slept on the floor of his office, and when he woke up the next morning, nikky was gone. he says the only thing she took was her toothbrush. her purse, her phone, all the tracking devices left behind. >> i go upstairs see what's going on. she's not there. >> reporter: he says she has been breaking down mentally for some time, and just walked away. >> this is the weirdest thing, okay? this is really freaking me out,

okay? this is not the first time she has run away, but she has never been gone overnight. >> reporter: matt overshares with the cop on the phone telling him the fight is about sex in detail. >> on the way home, i said to her, you know, hey, you know, because i wanted sex, but the sex we have been having wasn't anything special, you know? so i said, how about you put on an outfit? that might have set her off. >> reporter: he said, maybe she is in a hospital suffering from a breakdown. >> my wife has a long history of some kind of mental imbalances. okay? >> reporter: now matt says he has had enough. he is done with his crazy wife. >> i told her if she doesn't straighten up, i'm going to divorce her. i saw an attorney about it yesterday. >> reporter: that's right. before police have even launched a search, and before matt spread the word that nikky had gone missing, he had hired a lawyer to divorce her. >> what was that about? >> i couldn't tell you. my response to, that and reaction to that was, who does

that? it was all about him. it was never a frantic, where is my wife? >> reporter: as if divorce is not enough of a threat, matt goes down to the courthouse to fill out paperwork to have nikky committed. here he is telling his brother-in-law about it. >> i was at the courthouse swearing out a warrant for niqwu for involuntary committal. >> reporter: a multigenerational civil war is breaking out with matt and his young daughters about the southern in-laws, and her daughter, alex. >> my mother was the farthest thing from crazy you could get. her family has a different take. >> reporter: and they are angry that matt took two days to tell them she is missing. >> she wasn't worried at all about finding his wife. she was concerned about making sure that he stred the story that she was insane. >> reporter: so a week after she

vanished, he helps organize a search, in order to get the community involved. more than 100 volunteers, all in red spread out through the neighborhood. matt was not among them. skipping what may have been the shortest search in the history of missing persons. ten minutes after friends and family had formed the grid -- >> i saw a huge, big pile, and it looked like it was covering up something, so i started kicking away at it, saw her body and her hair. >> i heard somebody scream from the woods, and i -- you know, so i went up there to see what they had uncovered, and it was my sister. >> oh, dear god. >> family members cry out as a -- >> we're roping this area off. >> when firefighters and police arrive after minutes looking for niqwe lively.

>> i blacked out. >> reporter: she was found nude, less that a mile from her house. if she was running away, she didn't get far. >> her body covered in leaves. >> reporter: the finger-pointing began. this is amy moments after her sister's body is found. >> he waited two days to even report her missing. and he told me they had a huge fight and that, you know, she wasn't well, and she had been having graekdowbreakdowns, but r two weeks ago, and she was fine. >> reporter: the search is closed, but is this murder? >> the investigators are talking with her husband, and searching the couple's home, but police say right now, he is not a suspect. >> reporter: certainly, matt's personal setup will prove he had nothing to do with his wife's disappearances. what better alibi witness than 21 cameras? >> here's a man waiting far crime to happen every day. sitting in his office, looking

around. one finally happens, and you have no pictures of it. >> correct. >> reporter: when we come back -- when the cam

>> announcer: "20/20" saturday continues with what the cam aer didn't see. once again, jim avila. >> reporter: take a good look at this image of nique leili on her porch. hours before she supposedly walked out on her husband matt. it's the last picture of her alive. because, believe it or not, in this house tricked out like a small casino with 21 cameras, none of them managed to capture a single image of her final exit. >> so did you as an investigator think, well, this might be easy? there's cameras all over the place. he's got a recorder here. you might get some evidence off of this. >> correct. >> and did you ask him, can i see the night? >> he stated that when he came back to his office he realized the system was turned off. >> reporter: cue the chorus. how convenient -- and

suspicious. the most puzzling tape gap since watergate. only this isn't just 18 minutes. it's two days' worth of critical video, nowhere to be found. >> you would think we'd have it on video. i mean, this guy was serious about his video surveillance. >> reporter: matt leili tells police that after his wife had that cigarette on the porch -- the last time she was ever seen on the night of july 8, 2011, his elaborate monitoring system designed to watch every move simply went dark. matt's theory -- she stopped by his office where he was sleeping on the floor and pulled the plug on her way out the door on her crazed walk into the night. >> he said she turned off the system. >> reporter: without him knowing it? >> correct. >> reporter: even though he's in the room? >> correct. >> reporter: getting no help from matt's cameras, investigators turn to nique's body under the branches. >> the body's telling you something else. >> yeah, the body's definitely telling us that she didn't walk

there. we're working this as a homicide. >> reporter: then there is the condition of her bare feet. >> that's something that's very telling of, you know, of a body being placed is the clean feet because if you're running around the neighborhood, you're going to get cuts. i mean, these were pristine. the nail polish is clean and not nicked up. >> reporter: after an autopsy, the toxicology report reveals a tantalizing new piece of evidence about nique's last hours. in her system they find high levels of ghb, the date rape drug. >> in hundreds of cases, accidentals, overdoses, homicides, suicides, i've never seen ghb in a toxicology report. so that caught my attention immediately. >> reporter: remember, matt told the police the big blow-up that night was over sex. he wanted it, she didn't. but now there's evidence, somehow he had his way. something he failed to mention in his phone conversation with the cops. >> i said, listen. okay, this has gone on far enough, all right. i'll go downstairs, once again, and sleep on the couch. you go to sleep. we'll talk about this in the morning.

>> reporter: but the autopsy is most notable for what it does not reveal, the georgia summer is a killer's accomplice. >> we don't have an indication at that time, because of decomp and seven days out in july heat, of exactly the cause of death. >> reporter: there are no bullet holes, no knife wounds. no blunt force trauma. >> reporter: you thought she had been strangled. but there's no fingerprints either, right? and there's no marks around her neck. >> right. because of decomp, we don't have the telltale signs of strangulation. >> reporter: matt leili is definitely a suspect in his wife's murder. in fact, the only suspect. but there is not enough evidence to charge him. nique's family is beside themselves. her daughter alex almost feels guilty. >> like, there was something i wasn't doing to help fight for justice. there was something i was missing. sometimes you just wanted to scream at the rooftop. you know, he did it. do something. >> reporter: matt cuts off nique's family. isolating his daughters, they skip a memorial for nique. they don't even go to her funeral. he stops talking to police too.

>> police say matt leili is not cooperating, refusing to meet with them. >> reporter: the case is growing cold. and worse yet -- the day before what would have been matt and nique's 14th anniversary, sidney's cove is being vacated. >> today we found two moving trucks in the driveway. >> reporter: matt leili is moving away from nique's accusing family. >> there is no recourse so we feel very helpless. >> reporter: and the questioning georgia cops. >> as far as restricting his movements, we don't have any right or reason to do that right now. >> reporter: starting a new life 1,000 miles away in a hilltop house in rural londonderry, vermont. and he is taking amanda and rebecca with him. well, he's gone away, alex, but the real downside is your sisters have gone away too. >> it breaks my heart. to be completely honest, it breaks me down. i practically helped raise those girls. >> reporter: time is moving. but the case is not. alex, nique's oldest daughter, is planning her wedding with no mother of the bride. the other two daughters are now

teenagers. sydney's cove is foreclosed and sold off. a family divided. a case frozen in time -- but not forgotten. at police headquarters, located poetically on hi hope road, sits sergeant john richter, unwilling to give up on hope. he spends an entire year listening to what it's like being watched and controlled 24/7. >> i'm supposed to live my life running around wondering where a recorder is? what e-mails are being read? >> who brought that on themselves? >> no, matt. people don't live that way. >> reporter: 1,200 hours that he says reveal to him, the only crazy thing about nique was that she was married to a monster. >> [ bleep ]. lower your voice! i am not going to sit here and listen to this [ bleep ]. >> reporter: matt shows he is just as capable of losing his temper and according to nique -- using his hands as well as his voice to abuse her. >> if i wanted to do harm to you

i could have done it. you think i'm going to harm you? >> i don't know, matt. you tried to tonight. >> i did not. >> [ bleep ]. with 6'5", 250 [ bleep ] plus pounds, with your hands around my throat. you had me pinned to the [ bleep ] wall. >> all my homicide victims over the year, i've never met anybody. but after listening to these recordings, it gave me the -- you know, ability to know her. >> reporter: you liked her. >> i think she was a wonderful person, a wonderful mother, and by all accounts, she was a wonderful wife. just couldn't do enough for one individual. >> reporter: and you became determined to get this solved. >> i wasn't going to give up. >> reporter: that devotion leads to a big break. something as good as a bloody fingerprint hidden deep inside matt leili's computer. >> this was enough to tip the scales. >> reporter: control, alt, arrest. matt lieli, about to find himself in handcuffs.

and his teenage daughters, staying loyal to their father. how far will they go to prove daddy didn't do it? jail house pho

>> announcer: "20/20" saturday continues with what the camera didn't see. seems like over the years, i must have passed this place hundreds of times and i always thought of her. i'd always stop and look. >> reporter: as years passed, some may have figured hell would freeze over before police would solve the strange case of nique leili, found dead near her home in the atlanta suburb of lawrenceville. >> it's a day much unlike today. it's, you know, not snowing. it's july. and it's hot. >> reporter: it is definitely freezing on this day, more than four years later, as cold case cop john richter leads us to the little woods where her nude body was hastily buried under dead leaves and branches. >> reporter: where was it exactly? >> it's right in this area in here, amongst these -- these trees.

>> reporter: detective richter was part of the homicide team called out here the day her body was discovered. here in these woods, richter says he made a vow. >> that day when i was -- i was looking at this person who was placed here, it's like she didn't matter to anybody so i made a promise to myself that day, i would never give up on this case, or nique. >> i think we were all hoping for some sort of resolution by this time. >> reporter: for all matt leili's surveillance cameras, his radio shack syndrome, the fate of nique remains a blind spot. not so much as a flickering image or telltale echo. the story had always been, all that video evidence disappeared because matt leili's hard drives somehow got corrupted. >> now, corruption, it's -- it's a broad term, you know? >> reporter: could have been an accident. >> sure. >> reporter: could have been power went out. >> yeah, the lightning strike. you know? >> reporter: but then that cold case detective has a white-hot idea. he asks detective chris ford, a

forensics expert, to autopsy matt leili's hard drive hoping newly available technology will exhume any evidence buried inside the computer. >> oftentimes in my cold cases, i send off clothing, you know, so you might get a dna hit on some clothing that you didn't prior. well, in this case in particular, it was computers. it was the forensic stuff that i decided, you know, let's get a new, fresh look at the computers and the forensics. >> reporter: two weeks later detective ford casually drops the report off at richter's desk. >> and i look at it, and i see that -- i see the word "deleted." and i said, "no, these video files are deleted." he's like, "oh, absolutely. it was all deleted." >> reporter: now the evidence is clear. this was no accident. somebody intentionally deleted security camera video from the precise hours when nique had left, or been taken, from the house. the difference between the word deleted and corrupted for you is what? >> deleted, to me, means it was deleted by a person. somebody went in there and deleted, wanted this video gone. >> reporter: so now, you got to figure out who had the opportunity to do that.

>> right. >> reporter: and what did your investigation show? >> coincidentally enough, the defendant in this case is, by his account, a computer expert. a surveillance expert. >> reporter: it's all circumstantial but it's enough. the cops are now rebooting their case and the timing couldn't be worse for matt leili. that's because just about this time, he's back in town, in federal court in atlanta to testify in a civil lawsuit over nique's life insurance money. matt's lawyer in that case, jeff diamond. >> my perceptions is that he was a caring father. he was a big teddy bear, really. >> reporter: but big teddy bear has a big problem. >> reporter: were you there in the court? >> i was outside. >> reporter: matt leili leaves the courtroom and gets in the elevator. he thinks he's going to down to the lobby. but he's just going down. detective richter arrests him right there at the courthouse. did you get to put the cuffs on him? >> i did. and it felt good. >> reporter: we're finding out what led gwinnett county police to charge a husband in the

murder of his wife three and a half years ago. >> reporter: our affiliate wsb went straight to nique's sister amy and showed her this video of her nemesis in custody. >> it's a thing i've kind of pictured in my mind for a while but kind of had doubts as to whether i would actually ever see it. >> reporter: matt leili can forget about spending the insurance money. now he's fighting to keep from spending the rest of his life in a georgia prison. >> you have been charged with murder. >> reporter: matthew leili appeared tired and dazed as a judge read him the charges. >> reporter: dazed, maybe, but not confused. from behind bars awaiting trial, these recordings obtained by "20/20" reveal leili has an audacious plan to spring himself. >> make sure you tell people we have set up a youtube channel. to tell you the truth about what happened in our home. >> okay. >> reporter: his secret weapon? his own daughters, amanda and rebecca. they get father-knows-best

instructions from a jailhouse phone calls to launch a youtube crusade to defend him against nique's family. >> all these years we were told to be silent. to protect mom's image. we can't be silent anymore. >> okay. >> my daddy's now in jail because of these false allegations, it's time we tell the truth. that's even better. >> reporter: just listen, they execute his instructions almost word for word. >> and it's finally time for us to tell the truth and for us to call them out on their lies and -- >> now's our chance. >> say something insulting, from this, pathological lying family that doesn't want their dirty laundry aired, but the truth will come out. >> yes, sir. >> and the family is making sure we can't say anything. we can't argue to keep their dirty laundry from being aired. >> reporter: then matt uses his daughters to support his claim that their mother nique was crazy. >> my mom started pacing back and forth and she started kind of mumbling to herself.

>> don't forget to tell everybody about the youtube site because we want it on tv, okay? >> okay. >> love you, baby girl. good luck today. >> i love you too. >> reporter: leili got his wish. the girls' video makes news. >> as focus turns on dad. nique's own daughters take to youtube to defend him. >> the video was created by the man's two daughters. >> this is the teenage daughters, they made a youtube video in support of the father. >> it hurt a lot. they said some -- some hateful things about our family. they painted our mom like someone she really wasn't. >> reporter: as the mystery of nique's murder grips the streets of lawrenceville, just past scotland yard antiques, a street named luckie leads to the courthouse. where the two sides of the feuding family will meet again. >> reporter: happening now, lawyers are questioning the final potential jurors in the trial of a man who prosecutors say murdered his wife. >> reporter: still ahead, the murder trial of matt leili. the star witness, the victim herself, nique leili is about to speak to the jury.

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>> announcer: "20/20" saturday continues. >> reporter: under a threatening sky a year ago, a storm blowing in over the gwinnett county courthouse. matt leili is on trial, accused of murdering his wife. >> the new murder in georgia where a father of two is charged of killing his wife pretending she disappeared. >> before he even called police to report her missing, he calls

a lawyer. >> reporter: in court, two powerful teams head to head, prosecutor lisa jones. >> the evidence will prove, that matthew leili murdered his wife. >> reporter: tom clegg, matt leili's criminal defense attorney. >> he is falsely accused, pure and simple. >> reporter: exhibit "a," the autopsy. the medical examiner, often a casemaker for prosecutors, helpfully testifies she sure does suspect foul play. but if the jury is hoping for something directly connecting matt leili to his wife's death, this witness is no help. she can't even say for sure how nique died. >> they don't have a rock solid case at all here. >> i ruled the cause of death as undetermined. >> reporter: jurors such as kim muenster say when it comes to hard direct evidence. at least at the beginning of the state's case, they're just not hearing it. did any of that bother you? >> i thought from the get-go that you had to have proof, i was like, i need something more, i need something more.

>> reporter: and the prosecution got an unpleasant surprise when they called this woman to the stand, joanne lucie. matt leili's ex-wife. people in the courtroom say the legal bar suddenly turns into a singles bar. no objection, but it sure looks like the witness is flirting. >> okay. you're looking at him, periodically. >> he has beautiful eyes. he'd known that. he knows that i will always look at his eyes. he knows that. >> was that part of what attracted you to him to begin with? >> oh, yeah. his eyes. his height. his physique. >> okay. >> reporter: even though they'd been unhappily and briefly married 20 years before, there was still something. >> be that as it may, you still can't help but look at his eyes, can you? >> no. they're beautiful. >> that was astonishing, okay? she was flirting with him on the witness stand. >> reporter: goo-goo eyes aside, matt's former missus does manage to deliver some damaging testimony, confirming he got

rough with her. >> he would like to push you down to the ground, and pin you down. i'm not a very strong person, so i was easy to pin down. >> i guess she loves his eyes and loves his look, but she doesn't like the things that he did to her. >> reporter: because he did some -- some things that are very similar to what he did to nique. >> very similar. >> there were several nights that i would lay up at night, and listen to her say, "please get off of me. get off of me. you're hurting me." >> reporter: and prosecutor jones has much more ammo in her arsenal. the computer forensics from detective richter's investigation. the cameras were working when this crime happened. >> absolutely. it was intentionally deleted. >> reporter: but there is more. those recordings of a marriage on the brink. detective john richter takes the stand to testify about the year of his life he spent listening to nique. >> they give me a rare view into a victim's life, and how her life was leading up to her death. and i mean, i -- it was -- it

was gold. >> reporter: listen to this gem. not just a garden variety shouting match. richter, and apparently nique, believe matt once made something very much like a death threat. >> the words out of your [ bleep ] mouth. i should've let you kill yourself so i didn't have to [ bleep ] do it. don't [ bleep ] deny it, because those were the exact words that came out of your mouth. >> i said you should've, i should've let you killed yourself, why should i bother, be the one to do it? >> reporter: and so here is the state's theory of the murder of nique leili. what do you surmise did happen? after she and matt come home from the movies, that last security camera gets a glimpse as she sneaks a smoke. very likely the last one of her life. >> he gave her some ghb just to lower her, her resistance level. and then, you know, they had sex. >> reporter: fed up with the fights over sex and money, and terrified that his wife and meal

ticket will leave with the kids, matt leili then makes certain his tiny wife nique will never raise her voice to him again. >> and at some point, she was asphyxiated by him sitting on her, or strangling her. >> reporter: so he killed her with his own hands? >> he did. absolutely. he killed her with his own hands, with his own body. >> reporter: the crime scene bears no signs of a struggle. the body, no defensive wounds. but a dead wife is still a dead wife. >> he's got to get her out of that house, 'cause the girls are going to get up soon. he puts her in the woods like that. now he's got to delete the video. the only video that would show how she left that house. >> reporter: okay, so, that's the theory. prove it, says matt leili. his daughters, amanda, now 17, rebecca, 14, are his best weapons. they arrive at the courthouse from vermont. one after the other, the girls take the stand to defend their father. >> is this gentleman here your dad? >> yes. >> okay. and you love him, right? >> of course. >> very briefly, describe the relationship that your mom and dad had. >> they loved each other. >> did they ever fight? argue? >> they did argue, yes.

>> did you ever see your dad hit your mom? >> no. >> did you ever see any obvious injures or bruises to your mom? >> no, sir. >> reporter: but for juror kim muenster, just the sound of those terrible fights. >> your hands around my throat. >> my hands were not on your throat! >> reporter: the despair in nique's voice. >> if you don't get off, i swear to god. get off! >> reporter: gave her sleepless nights. how hard was it to listen to her audio recordings? >> all i could think about when i would go to sleep is anytime i would close my eyes, that's all i would hear was, "get off me, get off me," her screaming. >> reporter: there is just one more lingering question in this trial, what does matt leili have to say for himself? rumors fly around the courthouse that he wants to take the stand. the judge even asks him. >> mister leili, have you had the chance to speak with your attorney about that decision? >> i don't think i can do it. i'm too emotional. >> reporter: instead, in closing arguments, defense attorney tom clegg throws his client's personality under the bus but claims the state fell far short

of proving he's a killer. >> he can be an argumentative s.o.b. he probably is pretty damn good at pushing people's buttons. but what does that have to do with murder? >> and you need to listen to her. >> reporter: prosecutor lisa jones has the last word. making sure the jury leaves the courtroom with nique's voice echoing in their ears. >> welcome to my world. you killed me a long time ago. >> find him guilty because that's exactly what he is. >> reporter: it's a friday afternoon. the jury has two things on its mind. lunch, and whether matt leili will be eating prison food the rest of his life. >> have you reached a verdict? >> yes, your honor.

>> announcer: "20/20" saturday continues with what the camera didn't see. >> reporter: i'm told by the bailiff that the jury has reached a verdict so we're going to ask the jury to come in. >> reporter: judgment day for matt leili, accused of killing his wife, nique. nearly five years to build the

case, 3 1/2 hours to decide it on a friday afternoon in georgia. this is the moment georgia, this is the moment nique's family hand in hand, they can hardly wait. >> i'm going to ask you at this time if you would stand and read the verdict out loud. >> as to count one, we the jury find the defendant guilty of malice murder. as to count two, we the jury find the defendant guilty of felony murder. >> and as soon as i heard guilty, i probably squeezed her hand so hard i'm surprised it didn't break, because he was like, did he say guilty, did he say guilty, are you sure? oh, my gosh. >> you got my hand too. >> mr. leili, is there anything you want to say? >> i didn't do it. and i'll be filing an appeal. >> reporter: matt and nique's younger daughters, during the trial, i estranged from her family, arrive in court just in time to hear their father sentenced for murdering their mother. >> i need you to stand up for this sentencing portion. i am going to follow the state's recommendation as to count one, and have you sentenced to life

without the possibility of parole. >> reporter: amanda and rebecca still have not given up hope walking out of court somehow convinced daddy will be coming home soon. >> he's filing an appeal and you'll see my dad. >> reporter: the main thing that's left is any kind of rapprochement with your sisters. >> as hard as this has been, and as much hatred that they've harbored, my door is always open. because i don't blame them. i blame him. it's his fault. i love them dearly, and i will always have open arms to them. >> reporter: nique's family wanted to meet some of the people they believe helped deliver justice. >> nice to meet you. >> it's a pleasure to meet you. >> reporter: they asked us to help arrange it and so nique's sister amy dropped by our interview with juror kim muenster. >> thank you so much. >> reporter: and finally, that detective who made the promise here at nique's grave, tells me it's time to turn the page. now that you're back here after the verdict, what are your thoughts? >> maybe now nique can rest in peace, and -- and know that at least justice was served. and her family can know that.

and, you know, now it's time for me to move on to another case. and, you know, hopefully bring some kind of closure to some -- another family. it's time to move on. >> closure for some of the family members, and one or development, matt and nique's daughters have been reunited with their older stepsister. >> attorneys have filed a motion for a new twirial, and that is scheduled for next month. >> for all of us here at aga "20/20," thanks for watching. have a good evening.