accident? >> she's got a huge gash on her head. something like that is not consistent with just falling down. >> a husband and father is suddenly under suspicion. >> he is crying. we're crying. he said, they think i hurt mom. >> three daughters stand by their dad. one prosecutor stands firm. >> he is holding his wife of almost three decades under the water. my job is to get justice. >> was it murder? welcome to "dateline." in this hour, a story that calls to mind the master of suspension, a plot out of an alfred hitchcock film. a young woman looks into her neighbor's yard and seeing something for a few seconds. a man, a woman and a moment that's unsettling. was it some kind of accident, a crime? maybe even a murder. what she saw and what she did would set in motion a chain of events that would divide a family and a jury. here is keith morris. >> it's unsatisfying not to have that answer. >> reporter: even if we have seen something or if we think we have. the question at the heart of the puzzle. is this woman right? >> i know what i saw. i know the conclusion of my story. >> reporter: of course she does. >> she didn't know what she saw. >> reporter: a question on which all the rest will turn. why don't we begin here? historic missions, smalli inspr suburbs. here is where chris and kristy hall had come to live out their golden years. they're a unit. >> these are the three daughters, courtney, the oldest is a teacher. brianna, a personal trainer. and ashton, the youngest, here just returned from playing professional volleyball in europe. and all of them, of course, have heard scores of times the story of how their parents met. it was 1978, christy had gone to see a relative at the air force base in nearby san bernardino and quite by chance while she was there, encountered a security guard who, to her at least, looked just like elvis. it was blair christopher hall, chris to his friends. >> apparently she was a little flirty at the gate. >> in short order, chris and christy got married. she was 17, he 20. and as the girls grew up, they said they never doubted for a single moment the powerful bond of love their parents with them and with each other. >> they were probably closer with our parents than most children. they're the parents i hope to one day be. >> christy the vivacious glue in the family, chris the mirror. >> my dad was kicked back and relaxed. thee they were a perfect balance i think. >> chris was a police officer in san bernardino until he was shot in the line of duty. then he went off to become police chief in two small towns in idaho. then in 2005, anticipating an empty nest and eventual retirement, the halls bought this place back in cala mesa, which they loved for its backyard pool and spa and life in the spring of 2007 seemed to have hit a sweet spot as ashton and brianna remember their mother telling them. >> we happened to be laying on the bed with her. she started talking. she was like, i am just -- i'm so happy that i have you girls and dad. >> it was kind of one of those conversations that you don't have every day. >> still, there was work to be done. it was not a new house, could use some remodelling, particularly the bathroom. courtney was still living with her parents as the work began. >> they were going to be doing the tile work and stuff so we wouldn't have a shower for that day. >> so, shower out of commission, they decided to wake up early, put on their bathing suits and rinse off in the outdoor spa before the contractor arrived at 6:45 a.m. it was june 7, 2007. chris got up first, turned on the spa to warm it up and then called brianna at her college dorm? san diego. >> here's your wake up call, babe. get out and go on that run. >> back at the house, courtney dozed through her first wake up while chris and christy made their way outside to the spa. just after 6:30 chris looked in on courtney again, second call, then headed back to the spa. life's last normal moments. 6:37 a.m. >> i got up out of bed. i was putting on my robe. and i heard this panicked, just panicked scream for my dad yelling for me. i ran down the hallway to the back porch and i saw him just trying to pull my mom out of the spa. >> we have an emergency. >> it was she who dialed 9191 as s -- 911 as she and her father struggled to lift their mother out of the spa. >> it was the worst moment in my life. >> is it possible for people to know what it's like to be in that situation in >> i don't think so. to see both your parents in the worst times that you've ever seen them. obviously my mom unconscious and my dad just panicked and for the first time in my life seeing him just that way, not knowing what to do. >> he was a cop. he was used to dealing with those kinds of things. >> he's a cop used to dealing with those kinds of things with people that weren't his wife. >> so courtney took charge. after calling 911 she started cpr on her mother with her father. emt and firefighter eric nor wood was the first to respond. >> he just started -- help my wife, oh, my god, help my wife, help my wife. >> chris kneeling beside his wife's side. so hysterical it was hard for the emts to help. >> it took us a little bit to get him out of the way. >> he didn't want to leave her. he was just holding her hand yelling her name. >> the paramedics worked on christy for more than 20 minutes. no vital signs, none. >> and no words to describe the fear and the anxiety. >> you're losing your mother. you're watching her go right in front of you. >> we tried to save her together and we just couldn't. >> the ambulance rushed her off to the hospital where she was declared dead. she had drowned in the family spa. a private family tragedy, except maybe not so private after all. someone was watching. for all the eyes that get itchy and watery near pollen. there's flonase sensimist. it relieves all your worst symptoms including nasal congestion, which most pills don't. and all from a gentle mist you can barely feel. flonase sensimist. behr presents: ordinary versus overachiever. behr premium plus, "behr" through it all with a top-rated paint at a great price. find it exclusively at the home depot. janice, mom told me you bought a house. okay. [ buttons clicking ] [ camera shutter clicks ] so, now that you have a house, you can use homequote explorer. quiet. i'm blasting my quads. janice, look. i'm in a meeting. -janice, look. -[ chuckles ] -look, look. -i'm looking. it's easy. you just answer some simple questions online, and you get coverage options to choose from. you're ruining my workout. cycling is my passion. hey, want thedone.est internet? and now, xfinity mobile is included. you can get up to five lines. you can save 400 bucks or more a year, which you can spend on a funk-tastic music video. ♪ dance party boom. ♪ simple. easy. awesome. come see how you can save $400 or more a year with xfinity mobile. plus, ask how to keep your current phone. visit your local xfinity store today. returning now to someone who was watching. here is keith morrison. >> on the morning of june 7, 2007, brianna hall was on the road from san diego driving home from college to what she didn't know, except that her elder sister courtney had called and it sounded bad. >> she said, there was an accident. you need to just, you know, come home right away. >> it was courtney who eventually broke the news to ashton and brianna. their mother, their father's wife of close to 30 years, was dead. but neither courtney nor chris waited at the house to tell the sisters what happened. or to comfort them, nor did they linger over the body at the hospital. they couldn't because father and daughter were escorted to separate squad cars and driven to the police station to talk about the accident. what was that ride like? >> quiet. i just remember crying the whole time. i couldn't comfort my father, he couldn't comfort me. when we got to the station, he said my dad would be a few more minutes. >> chris so frenzied at the scene had calmed down by then. he was a cop among cops, after all. he understood, he said, what was necessary to help them sort out what happened. >> i can't even start to imagine what you're going through, okay. just, you know, it was a death investigation, happy to do this. >> happy to help, he said. whatever would get him back home to comfort his daughters as quickly as possible. >> i didn't kill her. >> you were all so close. >> chris told investigators what happened. how as courtney slept he and christy were in the spa bathing. >> she got up, went in, went to the bathroom, got some more coffee, tried to wake up courtney, courtney didn't wake up and apparently she came back out. >> as christy returned to the spa, said chris, they passed each other on the patio. he went in the house, stopped by courtney's room, make sure she was awake, then went right back outside and saw his wife floating face down in the spa. he called courtney then, he said, and they began a frantic effort to revive her. >> from what, a fall. >> tell me in your gut what happened. >> i'm thinking she slipped in, she slipped or something. i don't know. that's the only thing i can think of. >> but chris apparently hadn't noticed the nasty three-inch laceration on christy's head, and here suddenly the point of the police interview is revealed. >> the gash she has on her head, she's got a huge gash on her head. >> okay. >> something like that is not consistent with just falling down. >> not consistent with just falling down? why would the police think that? >> i mean, you've been around for awhile. >> i know where you're going. no, there's nothing. >> why was this ex-police chief being questioned at all about the apparently disastrous accident that killed the love of his life? and the answer was right next door. when chris and christy hall took their outdoor bath that morning in june, someone was watching. her. >> i got up at 6:00, got my coffee. >> lyndsay patterson was on leave from her i.t. job in the navy visiting her mom who lives just over the backyard wall from the hall house. lyndsay was inside in the bathroom that faced away from the hall house and out onto the street when she heard a noise. >> it was a horrible scream. it was just something was wrong kind of scream. >> a woman's, she thought? she went outside to tell her mom. >> and i said, did you hear that scream? and she said, yeah, but i think it's just kids playing in the pool. >> kids, at 6:00 something in the morning? lyndsay walked over to the 6-foot brick wall between their yard and the halls'. she stepped on the planter and looked over the wall. >> at that point i saw a man with his hand, one hand on top of a woman's head. and then one hand on her back. and she was face down in the water. >> like something was going on? >> yeah. that's what i assumed. >> that is, she thought she was looking at a sex act in progress. >> i don't know why it didn't seem right, but something made me want to look again. >> it's 90 seconds she said between her first and second looks. and this time she said she only saw the man in the spa. >> he was leaning back, just relaxed in the hot tub. but i don't see her. he's got his elbows back, looking around like nothing. >> where did the woman go? lyndsay told her mom something seemed strange. >> she tells me, lyndsay, stop being knowsnosey, don't worry a it. but it just didn't seem right. it wasn't enough time for her to have gotten out and gone inside the house. >> so, said lyndsay, she went to the wall again, her third and final look. >> at that point he was getting out of the jacuzzi and he was in a very big rush. she's still nowhere to be seen. the look on his face was almost undescribable. it was almost as if he had just gone into another world. it was scary. >> it was instinct that told her something was wrong, said lyndsay. so she called 911. >> 911, state your emergency. >> so now, hours and hours later, the detectives confronted chris with lyndsay's story. why, they asked, didn't her story match his. >> so, am i supposed to believe the witness is lying? >> i'm not saying she's lying. it sounds like a truthful kid, whatever. i mean, i don't know. you know, i can't explain what she's saying she saw. >> so now that question we posed as we began, did lyndsay pattison really know what she saw? ♪ with this level of intelligence... it's a supercomputer. with this grade of protection... it's a fortress. and with this standard of luxury... it's an oasis. the 2018 e-class. it's everything you need it to be... and more. lease the e300 for $569 a month at your local mercedes-benz dealer. mercedes-benz. the best or nothing. with esurance photo claims, you could have money for repairs within a day. wow! that was really fast. so it doesn't have to hurt for long. that's insurance for the modern world. esurance, an allstate company. click or call. ♪ ♪ i want some more of it. ♪ i try so hard, ♪ i can't rise above it ♪ don't know what it is 'bout that little gal's lovin'. ♪ ♪ but i like it, i love it, ♪ i want some more of it ♪ we know you love it, so get more of it, with applebee's new bigger bolder grill combos. now that's eatin' good in the neighborhood. they feel that they have to drink patients that i see that complain about dry mouth a lot of water. medications seem to be the number one cause for dry mouth. dry mouth can cause increased cavities, bad breath, oral irritation. i like to recommend biotene. biotene has a full array of products that replenishes the moisture in your mouth. biotene definitely works. it makes patients so much happier. [heartbeat] after his wife's drowning death in the backyard spa, police asked chris hall to explain what happened that morning. what chris did not know was that his neighbor had also talked to police, and she told a very different story than the one chris was telling. here again is keith morrison. >> chris and christy hall's three daughters clung together in grief and shock all through the dismal evening hours of that worst of all days, june 7, 2007. waiting for this father to return from the police station and they wondered why was it taking so long. then the phone rang, and they had their answer. >> you know, broken up words and he's crying and we're crying, and that was when he said, they think i hurt mom. he was very upset. >> but he didn't sound surprised -- >> he was crying. he was crying. he was upset. >> very upset. >> but by the time police investigators were questioning chris, remember, they had heard from lyndsay patterson. and at the station chris's version of events in the spa differed in one crucial detail from what lyndsay described seeing that first time she peered over the wall and into the halls' backyard. >> that specifically, me holding her down in there, there is nothing that took place in that jacuzzi that would explain that. there was no sex. there was no -- i don't even think we had any contact when we were in the jacuzzi other than when i was getting her out. >> but investigators were getting a good look at christy's body and saw wounds that to them suggested a struggle, and more than one nasty blow to the head. so, the police had to choose which version chris hall's or lyndsay patterson's was more likely the true story of what happened. tom dove is a senior investigator for the riverside d.a. >> i think they felt there was enough to say this was not an accidental drowning. it was purely much more suspicious than that. >> and so before the night was over, chris hall was arrested and charged with the murder of his wife. the girls could stop waiting. he wasn't coming home. >> it was obviously a tragedy losing our mother that day, but this is a tragedy on top of a tragedy now. >> because knowing our parents -- >> the farthest thing from the truth. >> and one that felt infected by some kind of madness, said the girls. christy was the love of their father's life, the center of everything. how could anyone so happy in his marriage and his life be accused of harming her? and she was happy, too, they said as happy as she'd ever been. they knew it based on that mother/dau mother/daughter talk they had not long before she died. >> she kept reiterating how happy she was. me and bri didn't think much of it at that time, but that being the last time we actually saw her -- >> kind of burned in your memories. >> yeah. >> but right or wrong, the legal trigger had been pulled. chris hall spent almost two months in jail until his daughters received the payout from christy's life insurance policy and used the money to meet his million dollar bail. and then he went back to what was to be his retirement retreat, to prepare with the help of his daughters for a murder trial. >> that's very surprising to have a client in a murder case out on bail, but he was a special man and this was a special situation. >> these are attorneys who would eventually defend him, though at first they only heard about the case. steve harmon and paul gretch. you said two things there, special man and special situation. >> both of us can say this is a man we like and that we know and we don't feel he could have done anything like this. >> so chris hall and his daughters prepared for a trial which they hoped would make clear to everybody the police, the neighbor, the world that chris would not, could not, did not harm the love of his life. >> there was never in 30 years of marriage, never one moment of violence. there was no motive for this man to kill his wife. >> harmon and gretch had a look at neighbor lyndsay's eyewitness account and suggested it was not conclusive at all. it was tragically incomplete. >> she saw three snapshots. what is missed by everyone is the wife getting into the jacuzzi, slipping, falling into the jacuzzi, hitting her head, going unconscious, and drowning. >> see this sharp corner sticking out into the spa? hitting your head on this would certainly have opened a gash and knocked christy out, said the attorney. >> she didn't see what was really happening during the times when she was not looking. >> that scream that made lyndsay patterson look over the wall, lyndsay, they pointed out, was in the bathroom that faced the street. she wasn't in the backyard when she said she heard it. could have been anybody. and courtney, who was inside her own house near the spa didn't hear a thing. >> we don't think she's lying. she misinterpreted what she saw. >> in any way, lyndsay to a certain degree, concedes she didn't know what she was seeing in her glimpses that morning. >> something was wrong. >> and yet you hadn't really seen anything. >> i -- no, but i knew something was wrong. i don't know if in my brain i was putting things together, but from between the scream, the position that he was holding her, and not having enough time for her to have gone inside. >> it was like you kind of got three different snapshots. >> right. >> of something going on in there. >> right. >> and had to kind of work out what this was. >> yeah. you know, i wasn't thinking at that point oh, this man just murdered his wife. >> but now based largely on that account, chris hall would go on trial for murder. and it was a trial for his daughters, too. >> he loved her. they were each other's best friends and this is just -- this is not fair to him because he truly loved her more than -- more than anyone. >> and yet the prosecutor was going to try to prove that this family man and former cop murdered his wife. could it be done? 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ask your doctor about opdivo. thank you to all involved in opdivo clinical trials. we need to help more tocalifornians get ahead.d, that's why antonio villaraigosa brought both parties together to balance the state budget with record investments in public schools... and new career training programs. as mayor of la, he brought police and residents together to get illegal guns off the streets and keep kids out of gangs, and on the right path. that's antonio villaraigosa. a governor for all of california. i'm dara brown with the hour's top stories. the secretary of homeland security is issuing a warning to members of the cara van at the u.s./mexico border hoping for asylum in america. in a statement secretary kneel son saying the u.s. will enforce its immigration laws and secure the borders. t-mobile and sprint have reached an agreement to combine into a new company which would reduce the number of major cell phone providers to three. the deal would have to be approved by regulators. now back to "dateline." ♪ ♪ chris hall was charged in the drowning death of his wife christy. as prosecutors were preparing to lay out their case, hall's daughters stood by him proclaiming his innocence. would anything change their minds about their dad? here again is keith morrison. >> he is a hard charging man. ex-member in good standing of the san francisco d.a.'s office now senior deputy d.a. in riverside. that takes skill, persuasive powers. he would need them in the murder case against the former police chief and family man chris hall. >> mr. hall, on the surface, looks like a loving family man. he looks like a good father, was somebody that had the support of his family. >> so he did. he wasn't buying the loving father and family man bit. no, when he heard about chris hall's very obvious grief, the whaling that went on after the so-called accident, the phrase that crossed his mind was, it's an act. >> i think it was a wonderful performance by the defendant of acting like a bereaved husband. when you look at his actions, how little he did to save his wife. >> who tried harder to save christy? not chris, his daughter. >> she called 911. she did chest compression. she was the one who helped his wife. >> a matter of opinion. he poked around in chris hall's past as a police man and what did he find? >> this man had an uncanny ability to fabricate stories. >> seven years earlier while hall was chief of police in cascade, idaho, he was charged with and convicted of misuse of public money, em bezled $19,000, spent ten months in jail. a white collar crime, hardly murder. but what struck the prosecutor is that he says hall tried to cover it up. to plan a fraud, not just lie about it, but lie about it effectively. >> i think that was very telling about who we were dealing with. >> suddenly the prosecutors' prospects were looking better. at the trial, he made lyndsay patterson his star witness, of course, it was her story, after all, that got the whole thing started. but almost as important, he called the riverside county medical examiner who testified that those lacerations in christy's head could not, in his opinion, have been the result of a single accidental fall. and he argued the particular type of bruising on christy's face and body was a homicide. >> the fatality ands injuries were not consistent with somebody slipping and falling and then a rescue attempt. >> and there was a clump of hair in the bottom of the spa still entwined with a broken plastic hair clip. that, said the prosecutor, could only have come from a violent struggle. >> when you lose that amount of hair, it's not reasonably explained by any kind of fall. >> there were some minor hiccoughs in the case. lyndsay patterson, for example, was a little inconsistent about how long she looked over the backyard wall that first time she saw something going on. was it just a few seconds? or as long as a minute? but either way, said the prosecutor, lyndsay was sure she saw physical contact. that was the important thing. >> he was given the opportunity to explain any physical contact that could in any way reasonably explain what lyndsay patterson missaw. in other words, were they washing each other, were they involved in a sex act. was there anything that she could have misinterpreted. and at the end of the day, you're not just stuck with the fact that lyndsay patterson made a mistake. you have to actually believe that lyndsay patterson really hallucinated about everything she saw. >> and what made lyndsay's story all the more convincing, said the prosecutor, was she told it before finding out what happened to christy. she dialled 911 a full minute and a half before anyone from the hall house did, before lyndsay had any idea how it would end. here's what the jury heard her say in that call. >> and hold her there. >> she was still on the phone with 911 when chris hall came outside when he found his body floating in the spa and called out for courtney. the investigator tom dove. >> i heard it best described during the trial as a cosmic coincidence that someone could see something that they perceived to be more than just some kind of kinky action in a jacuzzi in the morning and then that actually turnout to be true, that a woman was actually drown ed in that spa. that is not a coincidence. that is what she saw. >> the prosecution's theory, somehow sitting in the spa that morning, chris was overcome by some private fury. who knows what. a hidden violence is what he called it. and then killed his spouse when he thought nobody was looking. >> chris hall ambushed his wife, grabbed her by the hair, slammed her head twice into the concrete edge. he's holding his wife of almost three decades under the water, showing absolutely no mercy, no remorse, and absolute desire to end her life at that point. >> and then the resistance. >> then gets out of the spa, walks into the house where his plan is to wake his 22-year-old daughter who he can use as an alibi witness. >> one little quibble. why? in fact, as convinced as he was of hall's guilt, he conceded the why was a problem. didn't legally have to know, he said, but he just didn't. there it was. >> it's emotionally unsatisfying not to have that answer, not to know the entire narrative of what happened. >> but you'd want to know why this guy married to this woman for almost 30 years, apparently happily, would suddenly turn on her and drown her in the pool. >> right. i'm not sure we got the answers to that specific question -- >> kind of an important question, isn't it? >> it's an important question, a question that we ask in all spousal homicides. >> so, proof enough? or reasonable doubt? almost three years after christy hall's death, a riverside jury would have to decide. if you spit blood when you brush or floss you may have gum problems, and could be on the journey to much worse. try parodontax toothpaste. it's clinically proven to remove plaque, the main cause of bleeding gums. for healthy gums and strong teeth. leave bleeding gums behind with parodontax toothpaste. and experience more adventure it's with audible.utside audible has the world's largest selection of audiobooks and for just $14.95 a month you get a credit good for any audiobook. if you don't like it exchange it any time. no questions asked. you can also roll your credits over to the next month if you don't use them. with the free audible app adventure goes wherever you do. start a 30-day trial and your first audiobook is free. just text listen17 to 500500 to start listening today. racing isn't the only and with godaddy, i'm making my ideas real. with godaddy you can get a website to sell online. and it will look good. i made my own way. now it's time to make yours. ♪ everything is working just like it should ♪ janice, mom told me you bought a house. okay. [ buttons clicking ] [ camera shutter clicks ] so, now that you have a house, you can use homequote explorer. quiet. i'm blasting my quads. janice, look. i'm in a meeting. -janice, look. -[ chuckles ] -look, look. -i'm looking. it's easy. you just answer some simple questions online, and you get coverage options to choose from. you're ruining my workout. cycling is my passion. the jury in chris hall's murder trial heard dramatic testimony from his neighbor lyndsay patterson. patterson claims she had seen hall in the spa with his wife moments before she drowned. she said chris hall's hand was on his wife's head and back while she lay face down in the water. now it was the defense's attorney to show that chris hall loved his wife, would never harm her, and that her death was a tragic accident. here again is keith morrison. >> chris hall's daughter sat through every miserable minute of their dad's trial for murder. here at the courthouse in riverside, california. their review of the prosecutor's portrait of their father, it was a lie, they said. >> it was hurtful for us to hear someone basically say that he knows our parents better than we do. and he knows our father is a sociopath and that we're blind to it, and he knows that there was hidden violence in our parents' marriage and we just didn't see it. you're basically telling us that we didn't know our whole lives -- >> there's no proof of that. >> chris hall had never been violent, argued the defense. had no motive, no reason to suddenly turn on his wife. it had to be a freak accident. so, said the defense, lyndsay patterson didn't really know what she saw. in fact, if she really witnessed chris hall drowning his wife, why then didn't she claim to see christy's body in the spa when she looked again? didn't make sense. but the highlight was the hall daughter's testimony, emotional, quite powerful. so it put prosecutor tronsky in a strange position, at odds with the victim's own family. it was so clear. we had any inkling he had done this, believe me, we would have said so. we would have seen it. >> i think that's what they truly believed in their hearts. and, you know, it weighs on me greatly, but my job is to get justice for christy hall. >> now it was up to a jury to decide. after six days of testimony, two days of burt stronsky was disappointed, too, and was determined to retry the case. but first he sent his investigator on a mission to explore the life and marriage of chris hall. and what do you know? in idaho where hall had been a disgraced police chief, the investigator uncovered a startling accusation. >> chris was a great, great con man. >> former los angeles police officer jerry winkle is a county commissioner up in idaho now. but once upon a time, he was chris hall's friend. that is, before a night of poker and booze when he said hall made a disturbing revelation that he'd shot himself in the leg when he was a cop in order to get medical retirement benefits. >> chris had been drinking beer and he came right out and told me that he had shot himself. >> but there was more. d.a. investigator tom dove had discovered a secret, not in chris's past, but in christy's. >> there had been infidelity in the marriage for six years prior while chris hall was in custody in idaho. >> christy's affair was relatively brief, years earlier. but she'd been in phone contact with the man just days before she died. had chris found out? impossible to know. but when investigator dove talked to christy's coworkers at the clinic where she was an exray technician, several ever them said they noticed an unusual change in her usually vibrant personality. one coworker told us more. >> she told us she was contemplating a divorce. >> if true, and it was only an if, it might well persuade a jury. and also prosecutors tronsky needed to explain what lyndsay patterson saw or didn't see. why didn't she see christy's drowned body when she peeked over the wall a second time? >> we were not able to explain to the jury why she didn't see christy at that point, and i think that allowed the defense to make the argument that christy hall was inside. >> the prosecution hired a water expert to do a recreation of hall spa. andrea zafaras has been assisting nationwide with investigations the past 20 years. she got in the spa and videotaped where lyndsay was watching. >> from the center of the pool and towards where lyndsay was standing, anywhere i was laying, you could not be seen from lyndsay's viewpoint. so once i sank below the surface and hit that bottom, you could not see me at all from lyndsay's viewpoint. >> and now the prosecutor was ready. in may 2011, one year after the first jury dead locked, bert stron ski went back to court with a brand-new panel of hall's peers. he heard medical experts testify about injuries to christy's head. and heard lyndsay's 911 call. christy's coworkers testified for the prosecution, and jerry winkle traveled from idaho to tell jurors what he thought of chris hall. >> i was ashamed to admit he was once a police officer. >> but if the prosecution upped its game between the two trials, so had the defense. that's when well known attorney steve harman and gretch entered the scene and they came out swinging. that story about christy's affair, for example. >> there's a shadow hanging overall of this stuff, very human sort of shadow, which is that she was having a little affair, right? had a boyfriend. >> yes. if the husband knew about it, but the wife never, ever mentions it and tells the husband, no one tells the husband. >> quite right, said the judge. and because there was no evidence that chris knew about his wife's affair, he ruled it out of the trial. the story about hall shooting himself for retirement benefits -- >> that was just absolutely a lie. that's wrong. there was never, never any evidence or indication or not even a moment's breath that he shot himself. >> anyway, the story was prejudicial, said the judge, so he threw that out, too. as for what lyndsay patterson said she saw, chris hall holding his wife's head under water, the defense had prepared its own visual demonstration, had taken pictures from her angle at the wall to show that it could look like two people were touching in the spa, even if they weren't. >> this is what she described seeing in her testimony. but on the close-up, what do you notice? >> they're not touching but they're in position where they could be. >> but that's different than actually touching. >> again the hall daughters were there every minute. their father's enduring champions. this time more family members came to court. two of christy's own siblings testified for chris. >> they said the same thing. we have not a doubt in our minds that this was not a moment of violence. this was not a murder. the victim's own sister and own brother, that is an amazing thing to see. >> perhaps it was. but listen to this. the defense had one more very significant witness, a witness who oozed credibility. the sitting medical examiner from neighboring san bernardino county who stuck his neck way out to disagree publicly in a court of law with the medical examiner from riverside. >> he found this to be an accidental death, not a homicide. >> this was not some ordinary hired gun. this was a public official who said straight out that christy's head injuries could and perhaps should be explained by an accidental fall. >> he didn't rule out homicide. >> he didn't rule out homicide, but he said the accidental drowning. what -- i have always been astounded by with this case is that the hall family lived so close to the san bernardino border, if cristi had slipped and fell four or five blocks over, the pathologist in that county would never have filed criminal charges. an accident of geography. >> so now a second jury would have to sort through these two sets of allegations, these two opposing realities, and decide whether chris hall would turn and embrace home and his loving daughters or a pair of handcuffs and a life in prison. my bladder leakage was making me feel like i couldn't spend time with my grandson. now depend fit-flex has their fastest absorbing material inside, so it keeps me dry and protected. go to depend.com - get a coupon and try them for yourself. these are the specialists we're proud to call our own. experts from all over the world, working closely together to deliver truly personalized cancer care. expert medicine works here. learn more at cancercenter.com chris hall's first trial ended in a deadlocked jury. but with new evidence presented by both sides during his retrial, the jury was able to reach a verdict. now, with the conclusion to our story, here is keith morrison. >> may, 2011. for the second time, 12 men and women of riverside county, california, filed out of the courtroom, a second jury, to make a life decision about chris hall. did he murder his wife? which of the medical examiners should they believe? whose account of the defendant's character and, perhaps most important, what did lindsay patterson see when she peeked three times into the halls' back yard. >> do you ever have those sort of little dark moments of the soul where you think, i may have misinterpreted, misremembered -- >> it's something i've thought about every day, whether i misinterpreted, whether i think i saw something that wasn't there. i didn't see everything. >> yeah. >> but i saw what i saw. and i know the conclusion of my story. i know it. i know it. right here. i know it. >> of course, chris hall's daughters say they know the truth too, real thing. in their hearts. >> i think that we were the three most critical jurors in that courtroom. believe me, if we had heard anything or had any inkling that our father could have done this, as much as it would hurt and as much as we love our father, we would want that justice for our mother. >> the jurors deliberated two days and then broke for the long weekend. it was memorial day. halls' daughters felt good. >> things can only go so wrong for so long before something has to actually go right for us. >> we just did a lot of talking about the future and this, you know, being over, this being finished and honestly i was concerned about dad and how he was finally going to be able to grieve for the loss of his wife. >> then it was tuesday, 8:45 in the morning. the jury gathered. and minutes later, a signal. they were ready. chris hall and his daughters rushed to court. and in the end it was very quick. guilty of first degree murder. their father would not be coming home. probably ever. >> he was being cuffed. and potentially put away for life. and yeah. it hurts. and we are angry about that. >> you can still hear those daughters. >> i can. >> thinking you unfairly convicted their father. >> absolutely. it weighs on me. but at the same time, i know who i am dealing with when it comes to chris hall. in fact, he is the one that's stolen their mother from them. >> it had been a peculiar fact of this case that the victims' and defendants' families stood solidly together against the prosecution. what no one knew was the truth was more complicated. after the verdict at chris hall's sentencing a letter was introduced. it was from another of chris hall's brother, billy carlton, who until now had said not one public word about the case. we would like to ask his honor for the maximum sentence, wrote billy. the pain that my family has suffered through this tragedy is unforgivable. >> i didn't want to hurt the girls. i had to say what was on my mind. >> there was a deep divide in christi's family, said billy. some of the relatives believed chris was innocent but he and he said others including cristi's uncle steve mundy urged on the prosecutor silently. >> half the family was convinced he was innocent and half was convinced he wasn't. that's hard to do when you have a big family and you all have to be together once in a while. >> when it involves a member as loved as cristi was. >> exactly. >> does that explain why this kind of group of people in the family decided to just let justice take its course? >> we had talked about about it quite a bit. >> i think so. >> you have to know when to show up sometimes and when not to show up, just to keep what's left of the family as together as you can have it. >> thank you so much for coming. >> when it was over, hall convicted and sentenced to 25 years to life, some of cristi's relatives met with prosecutor strunsky and thanked him. >> thank you for putting the guy away, because he's a murderer. >> and the hall daughters, having lost their beloved mother, fought to save a father they adored, and having lost that fight, aren't quite sure what they'll do now. >> it's a devastating reality. it really is. especially for a family that -- you know, to say that we are close is an under statement, you know. to go from that to being not able to be there with each other, it's a -- it's the greatest heartbreak that anyone can ever experience, i think. >> that's all for this edition of "dateline: extra." i'm craig melvin. thank you for watching. due to mature subject matter, viewer discretion is advised. damn somebody got clocked. >> a jailhouse assault leads to one bloody inmate. >> who swung? who swung first? >> i didn't swing at all, he the one swung on me. >> and two sides to the story. >> we both swung on each other. mine's hit, his hit. mine's affecting him more that's all. >> in this picture you can see mr. green running down the street