of dateline, i'm natalie morales. thank you for watching. >> i'm craig melvin. >> and i'm natalie morales. this is dateline. ♪ ♪ ♪ >> i know my sister would've fought. we used to tell each other that if someone ever tried to hurt us that we would do everything we can to leave something behind, so the other one can figure it out. i believe that she was murdered. >> this is a very bizarre death. >> it was baffling from the start. a young woman dead at her millionaire boyfriend's mansion. >> 9-1-1 what are you reporting? >> i got a girl, hung herself. >> my heart started racing. >> you found her. >> i did.

>> detectives ruled it a suicide, but was it? >> at the scene knives, rose, a cryptic phrase. >> her hands were tied, she was naked. >> this was sending a message. >> that wasn't the only suspicious death here. >> no mom wants to hear that her son was a victim of a homicide. something happened at the top of the stairs. >> what really went on in that mansion. hear from the man at the center in his first television interview. you thought you had nothing to hide? >> i knew i had nothing to hide. >> the worst shock in probably my entire life. ♪ ♪ ♪ ♪ ♪ ♪ ♪ ♪ ♪ ♪ ♪ ♪ ♪ ♪ ♪ ♪ ♪ ♪ >> hello and welcome to "dateline." victims families have often described their feeling of loss simply as surreal. and so it was for both of the shacknai and the zahau families,

their tragedies were entangled in one rivetting mystery that enthralled the nation. at the center of the story to puzzling deaths and lingering suspicions. the search for the truth would pit the families against each other in a battle sparking more questions than answers. here is josh mankiewicz, with the "the mansion on ocean boulevard". >> some places feel secluded, insulated. secure. >> i can remember saying that and feeling that and saying nothing bad could ever happen here. >> here is coronado, california. just over a bridge from san diego. a town of beautiful beaches, people and homes. like this one, on ocean boulevard. except that in the summer of 2011, this mansion became ground zero for a mystery. >> this is a very bizarre

death. there is no doubt about it. >> well actually there's been plenty of doubt and plenty of theories. >> my sister was dead. and did a lot of things go through my mind? yes. >> secrets, both suspected and imagined. >> is it possible that other people know more than they're saying? yes. >> it's certainly possible. beyond that, it's hard to say for sure. especially when it seems everyone has a story to tell. and those stories lead to accusations, often with zero proof. >> people are gonna believe what they wanna believe with no evidence. >> paradise valley arizona was home for the shacknai family, but the summers they spent in coronado were special, for dina and her son max. >> max loves the beach, he

loved the water. he used to tell me on the way to coronado, mommy this is our place. >> she and maxes father jonah met in 1997. >> we had an instant connection, it's very rare you meet someone like that. >> they married in 2001, a second marriage for jonah, who was already the father of two. he'd gotten rich owning a pharmaceutical company. she went back to school to get a ph. d. in developmental psychology. and then along came max? >> and then along came maxie. >> he's almost told the edge. oh my. he did it. how do you feel max shacknai? >> he was an active kid who loved sports and performing, for his mother and her camera. >> mom. this is my song, right? >> it is. >> during one of those summers in coronado, a mansion on ocean boulevard was on the market. >> i said let's go by and look. >> they bought it in 2007. but soon there was trouble in paradise, and a bitter divorce

in 2009 when max was four. they shared custody and worked to be civil, and it wasn't long before jonah met someone new. >> max told me about it and i said, maybe i should meet her and he said, that would be great, mommy. >> rebecca zahau was 32 and born in myanmar. she'd moved in the u. s. in her twenties. you were okay with her spending time with max? >> max said he had feelings for her, he liked her. at that time i had no concerns because i trusted that jonah, based on our history, max would be safe there. >> and safe in coronado, where nothing bad is supposed to happen. >> tell the operator what is

going on. >> hello -- >> july 11th, 2011, max was staying with his dad and rebecca. dina ws in conorado, too, at a home down the street that is when jonah called her. >> he said dino you have to get here right away. >> as rebecca explained it to police jonah had been at the gym, six-year-old max was home with her. rebecca said she heard a crash and found max on the floor near the staircase, the mansion's heavy chandelier had fallen to the floor next to him. rebecca said max wasn't breathing, she started cpr. rebecca's 13-year-old sister xena, who was visiting, called 9-1-1. >> my sister is trying to resuscitate a boy. >> i'm sorry she -- >> he can't breathe. >> police and paramedics arrived within minutes, jonah called dina from the hospital. >> when he tells me, thank god that she was able to give him cpr, i think to myself thank you, thank god. >> he's gonna be okay? >> he's gonna be okay. >> max was unconscious. dina and jonah took up a vigil at the hospital. jonah's brother adam flew in from his home in tennessee. you came out to support jonah?

>> correct. >> how well did you know max? >> i knew max well. he was a really wonderful kid. >> at max's bedside, jonah asked one of the doctors for his prognosis. >> the doctor said i don't know. i don't know, i'm not sure if he's gonna walk or talk. >> that sounds like the worst news that you could get? >> but it was not real. i would've bet my life on it that max was going to be okay. >> there was more bad news on the way. >> 9-1-1 emergency. what are you reporting? >> yeah i got a girl, hung herself in the guesthouse. >> what had happened in that house, police uncovered some disturbing clues? coming up. >> they located a female on the property. the victims hands and feet were bound. >> i guarantee you my heart started racing. >> who was this victim? >> okay. how old is she? >> i'd say about 30. >> 30? okay. when was the last time you saw her? >> last night. >> soon detectives would be investigating not just one puzzling death, but 2. >> it was the worst shock in

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and outdoor allergens, day after day. feel the clarity and make today the most wonderful time of the year. live claritin clear. >> the early morning hours of july 13th 2011, as family members kept a vigil by the hospital bed of six-year-old max shacknai, a breathless man called 9-1-1. >> 9-1-1 emergency. what are you reporting? >> yeah, i got a girl she hung her self. >> once again, police raced through the streets of quiet coronado island.

and once again their destination was the mansion on ocean boulevard. jonas girlfriend rebecca was staying there, jonas brother adam had spent the night in the guesthouse. >> you wake up, you walk out, tell me what you see? >> a woman hanging, at the time i didn't necessarily think to myself, oh my goodness she's bound, or whatever. but just rebecca's hanging. >> naked, bound hand and foot, rebecca zahau was hanging by the neck from the second floor balcony. >> my heart started racing. this is actually happening. >> okay. how did she? >> i'd say about 30. >> 30? okay. when was the last time you saw her? >> last night. >> even as he called 9-1-1, adams said he thought she was dead. but you try to do something

about it? >> i tried to do something, absolutely. it never really occurred to me that someone would look at this as a crime scene or something like that. that was the furthest thing from my mind. >> so you cut her body down? >> yeah. >> and? >> started cpr. >> to no avail? >> to no avail. >> when the coroner units arrived at the scene and located a female on the property who appear to be deceased. >> rebecca's sister, mary was hundreds of miles away in missouri when her husband doug came to her work to bring her the awful news. >> i remember him saying rebecca's gone. and i said, what do you mean? i just talked to her last night. >> in that phone call, rebecca told her sister about what happened to max.

it was the same story she told police. >> she said she was in the bathroom and she heard a loud noise, a loud crash, and when she came out max was there on the floor and the chandelier was close to him. he was unconscious. how did you describe jonah during those days? >> that he was upset. and it broke her heart to see him upset. >> they've met when rebecca worked for an eye doctor, and jonah was a patient. >> he came in for an appointment and started talking a next thing you know they're going out? >> apparently, yes. >> you are making an expression that makes me think that you thought that was not a particularly good idea? >> i never approved of the relationship, if that's what you're asking me. >> because? >> first of all, he's almost twice her age. >> her free spirited sister fell for jonah anyway. they seemed happy, they seem and love? >> i think my sister loved him in her way.

to her she was some what in awe of him to some extent. >> mary says that while rebecca and max were close, rebecca gave the impression she didn't get along well with maxes mom. and when max had his fall, mary said, rebecca worried how dina would react. >> she was upset about it and she said, jeanne is going to kill me. >> she said dina is gonna kill me? >> that's correct. >> rebecca seemed upset, stressed, you get any sense that she blamed himself for what had happened? >> she seemed stressed, but not inappropriately so. >> because everybody was stressed? >> everybody was stressed. and actually sympathize with her, maybe mention that, it has to be tough on you. how terrible. >> soon, rebecca's death became national news. in large part because of details revealed by sheriff's investigators. >> the victims hands and feet were bound, and she was completely nude. it has yet to be determined if this will become a criminal matter or will remain as a death investigation. >> in other words, did rebeca hang herself or was someone

else involved? >> a neighbor reported hearing streams the night before, was that rebecca? there was a scream that somebody heard, did you hear that? >> well, my windows were closed and i did not hear scream. >> meanwhile at the hospital, dina said she was only focused on max. she kept watch by his bedside willing him to open his eyes. it was saturday july 16th, 2011, five days after maxes fall. >> i notice that his eeg was just flat. and i thought that the machine was broken, and i am shaking the machine and i'm thinking, it's not working, it's malfunctioning. and then i'm saying the eeg machine is not working, it's not working. but it was working, six -year-old max was gone. and dina was devastated.

>> i mean, it was the worst shock in probably my entire life. >> a mother in shock and in mourning. but also questioning, how exactly had maxes fatal fall happened? others asked what led to rebecca's hanging? the mystery of this mansion was only getting deeper. >> coming up. ropes, knives, a curious phrase on the scene. >> there was a message painted in black paint on the door leading to the room. >> but to some of the most curious thing of all, the police theory of what really happened. >> this is a very unusual circumstance. >> we conducted an experiment to determine if it is possible for a person to secure their hands behind their back in the fashion we found. >> when dateline continues.

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funeral was held for six -year-old max shacknai in arizona. just a few days later, rebecca zahau was laid to rest in missouri. back in coronado, the mansion on ocean boulevard was the focus of overflowing numbers of both questions and rumors. >> there is roughly 200 years of experience in the sheriff's homicide unit, they all agree that this is a very unusual circumstance.

>> rebecca was found hanging, naked, bound hand and foot. if it was suicide, it looked like a highly unusual one. and remember, rebecca was in the house when max shacknai fell. >> right now we don't see any connection between the two incidents. >> the sheriff's department investigated for two months. coronado held its breath. then at a news conference sheriff bill gore laid out the facts as his investigators saw them. >> was maxes death a homicide? >> the answer is no. it was a tragic accident. was rebecca's death a homicide? again, the answer is no, it was a suicide. >> sergeant dave said that the evidence show showed a sad tale in which one tragedy lead to another. when rebecca checked her voice mail just before 1 am, sergeant said that she heard a grim

message from her boyfriend, max's dad, jonah. >> that message that was left on her phone was to inform rebecca of max's grave condition and imminent death. >> did rebecca blame herself for the child severe injuries? and then, take her own life. the sergeant showed photos from inside the bedroom where rebecca spent her final moments. there was a rope tied to the bed, the other hand had been looped around rebecca's neck. there was also two knives in the bedroom, apparently used to cut the rope. everything was swabbed for dna. >> dna profiles were only from rebecca. >> so what about rebecca's hands and feet being tied, didn't that show another person was involved? sergeant nemeth said, it did

not. >> we conducted an experiment to determine if it is possible for a person to secure their hands behind their backs in the fashion we found. >> they even showed a video demonstration, and while tying ones hands in a suicide is uncommon, the medical examiner said that it is not unheard of. >> people do it, the thinking is that they bind themselves so that they won't change their mind midway through, it's unusual at first glance but it does happen. >> the location of the apparent suicide note was also uncommon. >> is there was a message painted on the door leading to the room, i'm going to show you a message, we will not be revealing with the message said. >> the investigation left some people unsatisfied. none more so than rebecca's family. >> i know in my heart she did not commit suicide. >> also unsatisfied, dina shacknai. sheriff's investigators illustrated their findings with this graphic. they said max was riding his scooter on the second floor

landing, somehow fell over the railing, then hit or grabbed the chandelier and took down with him. >> that sounds to me like max is a stuntman, briefly. >> why is that ridiculous, he's six years old? kids that age do crazy things, i was seven years old i'd trumped off of the roof of the garage -- holding an umbrella as a parachute. >> no. i'm absolutely positive. he was a very smart six year old. he was very athletic, he was very coordinated and he was a very careful person, a thoughtful person. >> dina did not just insist that something wasn't right, she opened her checkbook and hired her own experts. including doctor judy, a respected forensic pathologist who reviewed the autopsy report and photos and who also disagreed with the official conclusion. >> max had too many injuries to be explained with a simple accidental fall. >> the doctor thought that maxes injuries indicated that he had been assaulted before he fail. what's more she suspected whether the fall could happen

as the sheriff's department described it. measurements showed the railing was 32 inches high, six-year-old max was only 45 inches tall. >> his center of gravity was too low. even on a razor scooter, his center of gravity is too low to go over that banister. >> it all pointed to a chilling alternate scenario. according to the doctor, someone assaulted max, and then he somehow went over the bannister. in other words, this was a homicide. >> i would much rather have them say that this is an accident and here's what. no mom wants to hear that her son was a victim of a homicide. and if someone killed max, the doctor's theory focused on one person. >> i think rebecca was somehow involved, but how much she was involved and to what degree, she took that to the grave. >> that alarming suspicion was only the beginning. because it wasn't just dina who was investigating. rebecca's sister mary was equally convinced rebecca would

never hurt max or kill herself out of guilt. two women coping with terrible tragedies. neither willing to accept the sheriff's department's conclusions. mary was about to make some incredible accusations. and she wouldn't back down. >> could rebecca have been killed? a second autopsy magnifies the mystery. coming up. >> there are some deep bruising and internal bleeding, which couldn't be explained by the hanging. >> but could be explained by what? >> somebody knocking her down from behind and hog-tying her. there was a struggle. >> a twist was coming. >> did you have anything to do with rebecca's death? >> absolutely not. >> you thought you had nothing to hide? >> i knew i had nothing to hide. >> when dateline continues.

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here's what's happening. democrat charlie crist introduce carla hernandez who is running for florida's gubernatorial race. she has served as the president of the miami-dade commission since 2016. and will face rhonda scent is in november. a major baltimore area pizza restaurant has been called for 156,000 pounds of pizza that went without u.s. inspection. there has been no report of adverse reactions with consumption of the products. now back to dateline! ♪ ♪ ♪ >> welcome back to dateline. i'm natalie morales. police had ruled six-year-old max shacknai's fatal fall an accident. and rebecca zahau's hanging a suicide. but neither max's mom nor rebecca's sister were convinced. each woman suspected foul play. and one of them was about to

make an explosive accusation. continuing with our story, here is josh mankiewicz with "the mansion on ocean boulevard". >> the official investigation was over. the crime scene tape and evidence marker long gone. that said, an unofficial search for clues was just beginning. online message boards buzzed with theories from the far fetched to the implausible. through it all, rebecca's sister mary didn't buy the official finding of suicide. was she fragile? was she easily upset? is she the kind of person who would fall apart after a crisis? >> not at all. >> so when detectives said that voice mail, the one jonah left for rebecca with the grim news about max, may have caused rebecca to hang herself, mary wasn't having it. >> i was not about to have my sister's name smeared, and the world remember her as this crazy woman who committed her suicide because of a phone call. >> was all this just about how

rebecca would be remembered? after her death came some revelations, things even mary hadn't known about. like in 2005, in california, when rebecca didn't show up for work and just vanished. her boyfriend reported her missing to local police department. rebecca turned up a few days later, saying it was just a misunderstanding. you're persuaded that if she did sort of mysteriously disappear back then for a day or two, it was something that she willingly did and not some sign of mental fragility? >> i really don't know what happened at that time. >> now she said, she needed to know how rebecca died. she had rebecca's body exhumed, and media friendly forensic pathologists performed a second autopsy. his conclusion? homicide. >> was rebecca murdered? her family thought so. and eventually the case found its way to this man. >> it was intriguing from the beginning. >> san diego attorney keith

greer. >> the doctor did identify some of the bruising and internal bruising which couldn't be explained by the hanging. >> wait one second, it couldn't be explained by the hanging but could be explained by what? >> by somebody knocking her down from behind and hog-tying her, something along those lines. a struggle. >> plus greer said the force of falling nine feet from the balcony should've caused more severe injuries to rebecca's neck. he like the other doctor believed someone killed rebecca and then placed her body at the end of the rope. he began to develop a theory as to who. >> the writing on the door is a key to the case. >> remember the message painted on the door? sheriffs investigators declined to reveal what it said, greer eventually found out. the message scrawled in black acrylic paint read, she saved him, can you save her. greer believes the message was

not written by rebecca, it was written about her. she didn't save max? >> she did save max. at the time you have to look at it in context. >> remember rebecca said she did cpr on max after he fell. so at the time those words were written, max was still alive? >> max was alive. >> and maybe because of her effort? >> it wasn't maybe because of her effort, it was exactly because of her effort, and that's why it is the key to the case. because i know, whoever committed the murder, knew that rebecca had saved max. >> it was, he said, a small circle. mostly family. >> i had an eyewitness who put dina shacknai at the scene of the murder that evening. >> dina, the grief stricken mom. could she have blamed rebecca and then sought revenge? remember, mary recalled her sister saying, dina is going to kill me.

where were you when rebecca zahau died? >> i don't know when she died, but i was in the hospital all night. >> in 2013, keefe greer filed a civil wrongful death suit on behalf of the zahau family. based on his eyewitness he made dina as a defendant along with her twin sister nina. there was also third defendant, the man who called 9-1-1, jonas brother, adam shacknai. did you have anything to do with rebecca's death? >> absolutely not. >> greer disagreed. he pointed to those knots tied around rebecca's hands and feet. >> figuring out in the first place is hard, tying them almost impossible. >> he believed whoever tied the knot had to be an expert, possibly a sailor. and adam shacknai worked on the

mississippi river as a tugboat captain. >> when he ties things off he uses a figure eight, and then closes it with a single hitch or two, guess would not's are tied on both her legs and her hands? figure eights, tied off with a single hitch or two. >> sheriffs investigators had questioned adam extensively after rebecca's death. you didn't hold anything back from investigators? >> nothing. >> you help them to the extent that you could? >> yeah, exhaustively. >> you thought you had nothing to hide? >> i knew i had nothing to hide. >> and when investigators determined there was no evidence placing adam at the scene, they cleared you? >> they did. >> did you think this was over at that point? >> yes, i did.

>> it wasn't over. rebecca's sister was determined to hold someone accountable. i'm guessing that somebody said to you that filing a lawsuit, a civil lawsuit, to finance a criminal matter is generally an extremely unsatisfying way of pursuing justice? >> that may be, but my only recourse was the lawsuit. >> soon, they would start to get answers, just not the ones they expected. >> coming up. where was dina the night of rebecca's death? >> this eyewitness was adam, he was very clear, no doubt about it. >> powerful new video evidence and the dna evidence. where was it? >> adam shacknai admits that that morning he cut rebecca down, he loosened the ropes on her wrist to check her pulse. he gave her mouth to mouth resuscitation. >> and there's no dna? >> zero. >> when dateline continues. ladies, six minutes please... this is my life. it's not always “picture perfect.” plus i'm dealing with bleeding from uterine fibroids. enter myfembree,

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but a murder? >> yes, a homicide. >> tara has no law enforcement background. she calls herself an intelligence analyst. she and dina have floated several theories over the years. the current theory, whoever killed max, it was not rebecca zahau. these days their suspission is focued on information from a neighbour that has never been verified. a story of all wild party at the mansion the night before max's fall. >> he has not been interviewed by the police and has not come forward. >> but what connection it might have to max's death, you have no idea? >> i don't. but i think it should be explored. >> she said police never spoke with a neighbor but we did and he doesn't remember anything about a party. and max's dad, jonah shacknai, who was in the house said that there was no party. jonah says that he never doubted the official investigation, but wanted to rebut the theory offered by

dina and others. his lawyers hired the highly regarded investigative firm, krohl, the resulting report says that the evidence is consistent with an accidental, tragic fall. and there is no evidence of foul play, malice, or other non accidental ocurrents. how many people said to you, you need to let this go and move on? >> many. so many. >> even if she'd wanted to move on, it really wasn't possible, because dina, remember, was being sued by the family of rebecca zahau, who blamed dina, in part, for rebecca's death. through it all, dina stuck to her story that she'd been at max's bedside at the hospital the night rebecca died. even though the zahau's attorney keith greer had a witness willing to testify that he saw dina outside the mansion that night. >> this eyewitness was adamant. he was very clear, no doubt about it. >> and turned out to be dead

bang wrong? >> dead wrong. >> in april 2017, after four years of litigation, this security camera video came to light. it's from the hospital where max shacknai was being treated. the same night rebecca zahau died. clearly visible, dina shacknai. at some point you look at the footage and you realize, i'm wrong. and my witness is wrong. dina wasn't there, she was at the hospital provably. >> absolutely. i got mad. i got really mad. >> greer called a press conference to publicly eat some crow. >> when these pictures come out though, you can't refute them. >> he removed dina from the lawsuit along with her sister nina. and the zahau family attorney apologized to you, was that enough? >> he made a public apology. i would say that not as many people saw the public apology, as who saw continuous accusations against us. >> greer pushed forward anyway with just one defendant, adam shacknai.

that says to me, this is some scattershot attempt and you are suing everybody that comes into your line of sight looking for a sympathetic jury. >> that's it. a lot of people looked at it that way. >> why shouldn't that shatter the credibility of the rest of your case? >> i think the reality of it is that we always had adam involved all through the process. >> in the lawsuit, greer outlined quite a detailed and unsubstantiated narrative. he argued rebecca was killed not to avenge max, but instead during a sexual assault. greer's theory is that it began when rebecca stepped out of her shower and saw adam watching her. >> she then gets uncomfortable and tries to escape, screams for help, at 11:30 that night. >> he says that explains the screams heard by a neighbor. >> right after that, to silence her adam hits her at the back of the head knocks or partially unconscious and then he thinks,

wraps the black pink and he paints this phrase on the door. >> she saved him, can you save her? if i'm gonna kill somebody and try to make it look like a suicide, i'm not gonna write a cryptic phrase behind, i'm gonna write a phrase that said, i'm sorry, i'm guilty i did it. >> it wasn't staged to be a suicide. >> even greer says evidence placing adam at the scene is weak. adam shacknai have any marks or scrapes that there had been a struggle with anyone. >> none. >> same with adam's dna. >> it's pretty hard to get rid of your dna. >> hard to get rid of dna. all right. adam shacknai admits that that morning he cut rebecca down, he loosened the ropes on her wrist to check her pulse. he gave her mouth to mouth resucitation, he gave cpr pumps to her chest -- >> and there's no dna? >> and how much dna and how many fingerprints are found on the knife, the rope, her body, how much? >> none.

>> zero. zero. >> zero of adam's, that is. rebecca's dna and fingerprints were everywhere. according to greer, that means adam, who had no criminal history, knew exactly how to wipe down the scene, somehow removing his own fingerprints and dna, but leaving just rebecca's. of course, it could also mean that adam simply wasn't there when rebecca died, which is exactly what law enforcement came to believe. i'm guessing that if you walk in court in any case, and opposing council said, there is no evidence here, there are no fingerprints and there's no dna, and that is the proof of the case that i am bringing, you would think to yourself, i have a grand ball here. >> the absence of evidence isn't the evidence of absence. and so, we know it's murder because it's wiped down. we know it's not suicide. >> would a jury agree? greer had to prove that adam shacknai was somehow

responsible for rebecca's death. that his own actions made him liable. in a wrongful death civil case the standard is more likely than not. a significantly lower bar than beyond a reasonable doubt, which is the standard in a criminal case. it is however still a challenge, and when the case went to trial, keith greer would be against a top notch defense team. did you feel overmatched? >> i was so out gunned it was pathetic. >> two families connected by tragedy prepare to go head to head in a courtroom. coming up. >> did you attack her? >> no. >> did you sexually assault her? >> no. did you tie those knots on her body? >> no. >> would a jury believe him? >> i sat down next to him and said merry i'm sorry, this is probably not good news. >> when dateline continues. enamel is the hardest tissue in the body. it's the protective layer outside your teeth. pronamel repair is our first line of defense.

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rebecca zahau's death had been ruled a suicide but her sister mary was convinced she had been murdered by adam shacknai. adam insisted that he tried to save rebecca after finding her hanging from the balcony. now the two were facing off in a civil lawsuit. a jury would decide who was responsible for rebecca's death, and the verdict would leave both sides stunned. here is josh mankiewicz with the conclusion of "the mansion on ocean boulevard". >> the plans attorney, he has a

good imagination. >> adam shacknai said it was simple, he had nothing to do with the death of rebecca zahau. were you present when rebecca died? >> no. >> did you attack her? >> no. >> did you sexually assault her? >> no. >> did you tie those not on your body? >> no. >> are those a types of not that only a sailor would know? >> no. those are common knots. >> sheriff's investigators found no evidence adam was present when rebecca died. and they cleared him. that didn't stop rebecca's family from suing in civil court. the lawsuit, the long string of accusations, what do you think

is going on here? >> it's denial, it's they don't wanted to be seen that their sister committed suicide. >> we asked rebecca's sister mary about that. a lot of times, families do not want to admit that someone committed to side. because they blame themselves for not maybe having seen the signs, is that what you're doing here? >> no. and i have been accused of that multiple times, including the sheriff's department. >> is it possible that rebecca was depressed and you missed it? >> no. >> in march 2018 the wrongful death long sued began incendiary go. defending adam was dan web, former u.s. attorney and a veteran of many courtrooms. >> there is no evidence that shows that adam shacknai had anything to do with the death

of rebecca zahau. >> in particular, no dna or fingerprints from adam were found at the death scene. plaintiffs attorney keith greer called several experts who testified that the lack of physical evidence could show that adam had cleaned up after himself. >> there was nothing on the doorknobs whatsoever. as far as prince. >> and that's consistent with them being wiped down? >> yes. >> and a handwriting expert who looked at that message on the door. >> the writing on the door is more consistent with adams than rebecca's. >> greer also claims that rebecca had been sexually assaulted with a knife prior to her murder. his expert testified a steak knife found in her bedroom had her blood in the handle. greer said the sheriff's department had overlooked that

evidence. >> they never considered that. they never analyzed that. >> to defense called a forensic technician who does testified she did find the blood on the knife and with it a simple explanation. a recent cut on rebecca's right hand. and when greer asked her if the blood could've come from a sexual assault? >> i didn't see any evidence of that. >> no evidence. a point the defense hammered home. >> no fingerprint evidence. no finger evidence that was indentified or directed to adam shacknai. >> adams brother jonah took the stand, he called rebecca's death unfathomable, but said adam was not responsible. >> is there anything that adam has ever done in his life that would cause you to believe that

he ever would've done the acts that he is accused of in this case? >> never. anything, it's inconceivable. >> adam took the stand too. >> did you hit rebecca on the head? >> i never hit her back on the head. or anywhere else, for that matter. >> did you devise this scheme to try to cover up your wrongdoing by painting the saying on the door and making it look like she had been hanged by someone else? >> absolutely, positively, not. >> the case went to the jury. >> did you feel confidence deliberations began? >> i felt like we could possibly win very convincingly. >> less than four hours later, a verdict. >> i sat down next to mary and said, i'm sorry, this is probably not good news, this was it a decision that even keefe greer would be in for

quite a plot twist. >> number one did adam shacknai touch rebecca-- before rebecca zahau's death with the intent to heart hurt? the answer is yes. did that touching cause the death of rebecca zahau the answer is yes. >> yes, meaning that the jury found adam shacknai responsible for rebecca zahau's death. >> i just broke down. i was just like ok, i'm not crazy. i'm not the only one who believes that adam murdered my sister. >> that's not quite what the jury said. finding someone liable in a civil case is not the same as finding them guilty of murder. what's more, the verdict in this case did not have to be unanimous, and it wasn't. nine jurors found adam responsible, three did not. the jury did award the zahau family $5 million. >> courtrooms are supposed to be a place where justice is dispensed, was this about justice? >> no, it wasn't.

>> since this wasn't a criminal case, adam didn't go to jail, he returned home to tennessee and filed a motion for a new trial, which was denied in january 2019. then in february, adams insurance company and rebecca's family reached a settlement of $600, 000, and the case was dismissed. after the civil trial, the sheriff's department took a fresh look at rebecca's death. eight months later, that review also concluded that rebecca died by suicide. dina shacknai would like to see authorities reinvestigate her son's case. do you think they will reinvestigate max's death? >> i think it's the right thing to do. do i think it will happen? i really don't know. >> how does a mother ever truly accept the tragic loss of her child? the ripples keep on spreading to this day. in a place where nothing bad was supposed to happen. >> that's all for this edition of dateline, i'm natalie morales. thank you for watching.