a murky case. he got a friend to buy him a shotgun. said good-bye to the ivy league, and on a winter's day, drove home. that's all for this edition of "dateline." i'm craig melvin. thanks for watching. >> i'm craig melvin. >> i'm natalie morales. >> and this is "dateline." >> oh, please, god. why? >> it is the case that stunned parents everywhere, the dad whose young son died in the car. >> apparently, he forgot the child was in the car seat in the back and went to work. >> i know you didn't, baby. i know you didn't. >> i think any parent can put themselves in that situation. >> full denial, that it wasn't happening. >> then came the jaw-dropping news. police said it was murder. >> there was far more to the

story that we were beginning to realize. this guy clearly was leading a double life. >> oh, my baby. >> could any parent ever do this on purpose? inside this landmark case. >> there were a whole lot of secrets about to be revealed. >> yes, ma'am. >> ross and leanna harris's seemingly picture perfect world was shattered one hot georgia day when their toddler cooper was left in a car for seven hours and died from overheating. was this a horrific mistake or murder? here with unimaginable is andrea canning. >> you're watching as a police cruiser races to an atlanta

parking lot. a call for help over the radio. child not breathing. he had been found in the back seat of a hot car. every year an average of 37 children die from heat stroke after being forgotten or left behind in cars in the heat of the sun and parents pay the ultimate price for lives that are busy, distracted, sometimes overwhelming. police weren't able to save 22-month-old cooper harris is 2014 and his death in a hot car made headlines nationwide. >> new details in a tragic case we've been following. the death of a georgia toddler. >> but there was something different about cooper's story, something darker, because cooper's dad, ross harris, ended up being charged with a crime, accused not of forgetting cooper but of murdering him and his murder weapon of choice, prosecutors said, was a hot car. >> some disturbing -- >> even if you have seen the

headlines, there's more to this story you may not know. we'll take you to the scene, show you surveillance footage from that day and give you an in-depth look at the evidence. >> it sent chills down our spines knowing we were in the head of a murderer. >> we'll also talk to insiders who have never spoken out before. they say ross harris was not a killer but a doting dad. >> was he a proud dad? >> so proud. >> he loved that boy. >> a father who ended up on trial for an unimaginable crime. >> the entire case was a house of cards. >> like the people around him, you can decide whether it is the face of a dad who made the mistake of his life or a murderer. >> oh, my god. what have i done! ♪

>> ross harris grew up in tuscaloosa, alabama, and that's where his close friend billy kirkpatrick met him. >> you called him a massive dork. >> massive dork, yes. >> why did you call him that? >> because he's a massive dork. >> billy says ross was a lot of fun to be around. he remembers one beach holiday in particular. >> ross took his guitar and, like, walked up to people on the beach and started conversations because that's who he is. >> but ross seemed to settle down when he met his wife, leanna. she encouraged him to get his college degree. his cousin katie said leanna made ross want to be a better man. >> we said without leanna he would have been a lost little puppy. >> after six years of marriage, they moved to atlanta where he was offered a job at home depot.

>> what was it like for you when you first saw cooper? >> he was so beautiful. blonde hair, blue eyes. tiny little perfection. >> i have this vision of ross and cooper on the couch and ross is just goofing around with him and getting in the floor with him. it was hilarious. >> any extra thing that cooper could do, any milestone that he hit, he would share it with everyone. one of the conversations i had with ross, he said that it was so cool that cooper knew his name. and he said, and he loves to yell it at me. so instead of saying dad he would just go, ross, and he would yell ross at him all the time. >> it was ross who took cooper to daycare most mornings, and that was where leanna expected to pick him up on june 18, 2014. here she is arriving at the daycare. >> she got to the daycare and cooper wasn't there. >> leanna called ross to see if there had been a mixup but he didn't pick up, and then she had a worrying thought.

maybe ross accidentally left cooper at home. >> she texted her neighbor and asked her to just go look. she has a key to her apartment, go look, see if he's there. she's like, maybe the house will be torn up, it will be a little toddler tornado when she gets there but he'll be there. obviously he wasn't. >> leanna rushed over to ross's office to see if cooper was there. it was at home depot that a police officer tracked her down. their conversation was recorded as he gave her the worst possible news. >> there's going to be no easy way to tell you this. your child is deceased. i'm very sorry to have to tell you that. >> where's my husband? >> your husband is up at our headquarters right now. >> the officer explained ross had never taken cooper to daycare that day, that he had done the unthinkable and left cooper in his car for seven hours in the georgia heat.

>> has he ever done anything like that, for getting about -- >> no. >> do you know what might have made him forget about it? >> no. >> i think any parent could put themselves in that situation with their own child, and it is so hard to fathom being in a place like that. >> i think she was in full denial, like it wasn't happening. it was a nightmare, is what she said. i'm going to wake up and it will be fine. this didn't happen. >> leanna was taken to the cobb county police headquarters. ross was already there in an interview room, telling detectives what had happened. but to them something about ross harris and his story wasn't adding up. >> what really happened that morning? was it a tragic accident or something far more sinister? coming up -- >> oh, please, god. why? >> questions about a father's story. >> the antennas went up on the detectives when they heard that.

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ross harris sat alone in the place they call the box, an interview room at the cobb county police department. >> oh, please, god. why? >> he could barely keep still as he waited for detectives to

question him about the death of his son, cooper. he had a horrible story to tell. >> ross, just kind of run me through your morning today. >> prosecutor chuck boring was brought into the investigation early on. >> i think the main goal in a case like this is to get a timeline of the events. >> ross told detectives the morning had begun like many others. leanna set off to work early. ross set out for breakfast at chick-fil-a near his office. >> we do that approximately two to three times a month together. >> after they ate, ross said he strapped cooper into his car seat. >> i gave him a kiss. he gave me a kiss. what i do every time, it is my routine, and just today was just -- careless. i got in my car, and instead of going from here to here, i went straight to work. >> ross told police he'd simply forgotten to take cooper to daycare. >> i went to work as if he wasn't even in the back.

and i probably didn't even hear him because he falls asleep very easily when you drive a car. that was it. >> he said he didn't realize what he had done until hours later when he got in his car after work and started driving. >> i caught a glimpse of him in my -- when i looked to my right to change lanes. >> ross said he went flying into the closest parking lot and pulled a lifeless cooper out of his car. a bystander called 911. >> there is a baby on the ground. >> dash cam video from a police cruiser captured ross at the scene minutes later, pacing, hands-on his head. it also captured audio of ross exploding in anger at police. >> all right. all right, all right. >> they cuffed him and put him in a patrol car to cool off. and this is the moment police started wondering about the way

ross was behaving. he cried out one moment. >> oh, my god, what have i done. >> the next moment he seemed calm. >> we're going to sit here and talk to you a little bit. >> at the police station, detectives who interviewed ross thought his demeanor seemed a bit strange. they noticed he never shed a tear in front of them. instead, he was casual as they searched his pockets. >> lead guitar player at stone bridge church. >> okay, yeah. >> even jokey. >> and he was your partner in language. >> he is. if not, i'm doing really good. >> prosecutor jesse evans. >> you look at it and say whatever the reaction is you're supposed to have, that ain't it. >> what really got detective's attention was how much ross seemed to know about children dying in hot cars. >> the -- the worst fear for me is to leave my son in a hot car. and just recently there was a vet on -- on the internet who, you know, said even if you have

your windows rolled down and regardless, you know, i'm going to show you how hot it can get in a car. >> the antennas went up on the detectives when they heard that. >> detectives weren't in the room when ross was finally reunited with leanna, but the cameras rolled and ross showed a completely different emotion to his wife. >> you know i didn't mean to. >> i know you didn't, baby. i know you didn't. i know that. >> i didn't mean to. >> i know you didn't. >> i think my life is over. >> it's not over, baby. it's not over. >> ross pulled himself together and told leanna his story just like he told the police. >> i turned out of chick-fil-a and just went to work, like -- like it was nothing. he wasn't making a sound. you know, i think he fell asleep. >> he had some comfort for leanna, too. >> at least i know that he's in heaven right now. >> i know he is. >> i know he is. >> he's playing with all the

trucks in the world. >> oh, my boy. >> but it was something else ross told leanna that really got the investigators' attention. >> he said it while he was talking to leanna. you know, he was dreading how cooper was going to look when he got him out. >> almost like -- >> he knew what was there exactly. he knew what was going to be found. >> they were also struck by how calm leanna seemed to be and by this surprising question. >> did you say too much? >> detectives wondered what she meant. they came back into the room and told ross he wasn't going home. >> he's going to jail. he's being charged. >> investigators thought they had enough to prove ross had been negligent by leaving his son in the car. >> his negligence caused the death of your son. >> and their investigation was just beginning. later that night when katie reached leanna on the phone, she told her she had been sitting outside her home on the

sidewalk. >> and she's told me that, you know, as long as she sat outside she could pretend like this wasn't happening because once she goes inside, you know, there's an empty bedroom where cooper's supposed to be. >> an empty crib. >> there's his toys, his pictures. it is not real if she doesn't go inside. >> katie says leanna was numb without her child and her husband. >> did she go through that emotion at any point, i'm angry at you, how could you do this? >> i don't know she was ever angry at him. >> you go through that scenario as a spouse, would i be able to understand? >> she is such a composed woman and her faith i don't think would let her be angry at him for something he did not do intentionally. >> as cooper's family began to grieve, detectives started building their case against ross harris, and what they found convinced them this was no simple case of negligence. they believed this was

premeditated murder. >> coming up -- >> did he lie? >> he absolutely lied. >> there were a whole lot of secrets about to be revealed? >> yes, ma'am. >> when "dateline" continues. when you combine ancestry's dna test with its historical records... you could learn you're from ireland donegal, ireland and your ancestor was a fisherman. with blue eyes. just like you. begin your journey at ancestry.com like nothing you, ncy or she, has ever seen.

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after his son cooper died from being left in a hot car, ross harris was brought in for questioning. even though harris was apologetic to his wife,

authorities were not convinced. they charged him in the death of his son. the father may have been negligent in forgetting cooper was in the car, but were his actions intentional? here again is andrea canning. >> reporter: the day after cooper's death ross harris sat in the cobb county jail. his family and friends were in shock. billy was a paul bearer at cooper's funeral. >> have to carry that -- that little casket, you know. >> katie says the family grieved in full view of the media. >> i felt like it was a circus and we were the monkeys. everybody was watching us. >> police were watching too. prosecutor susan treadway. >> we have to review all of the evidence. we have to see where it leads us.

>> investigators pulled surveillance video from the chick-fil-a restaurant where ross said he took cooper for breakfast. there they were, father and son. >> nothing really seems out of the ordinary. it looks like a father and son grabbing breakfast. it doesn't look like a child killer waiting to carry out his crime. >> i would say completely to the contrary. i looked at the video when i first saw it and i thought it seemed very out of the ordinary. in particular the way that he was introducing cooper to some of the workers there and how they eventually described it to us as being almost like he was putting on a show, almost like he was going out of his way to do that. >> maybe more interesting prosecutor jesse evans says is what the video showed about cooper. >> cooper is wide awake. didn't appear to be sleepy or anything like that. >> ross had told detectives cooper was most likely asleep in the car and that's why he had forgotten about him, but detectives were skeptical. the entire drive from the restaurant to ross's office was

only about half a mile. >> and there was something else investigators found interesting about ross's route that day. it is how quickly he would have forgotten cooper if it happened the way he said. we decided to retrace ross' route that day. we're making a right out of the chick-fil-a parking lot, and we have to cross a lane of traffic just as ross did to get to this u-turn right here. he made this u-turn very quickly, and then headed toward this intersection up here. this is a critical intersection coming up. it is here ross had to make a decision, going left would have taken him to cooper's daycare, going straight on would have taken him to work. he went straight on. that means he for got cooper was in the car within two minutes of strapping him into his car seat and giving him a kiss. >> it does seem remarkable that we can forget a child in a car very quickly. >> dr. david diamond is a neuro scientist at the university of south florida. for a decade he has studied hundreds of cases of children

who die in hot cars. >> in a recent case i was involved in in australia, a mother drove one block, a 30-second drive, and in a matter of that brief time for got that her child was in the car. >> what we're talking about here, there is actually a name for this. >> this is referred to as forgotten baby syndrome, which actually describes a phenomenon in which normal attentive and loving parents for reasons we don't fully understand lose awareness their child is in the car. >> diamond says it can happen to anyone. distraction and exhaustion often play a role. he adds, once the child is forgotten, the brain plays a dangerous trick. >> what is remarkable is these parents create an artificial memory that the children are actually at daycare and that they are safe. >> but in this case, investigators were increasingly convinced that cooper's death had nothing to do with a slip of the mind. >> there's been a lot made of how could you forget something that quickly.

now, i don't know what was going through this man's mind, but i do know i have five children and i forget things in an instant. it just happens. is it fair that -- to say, oh, he wouldn't be able to forget something so fast? >> this is something that if you look at it alone, can somebody forget something that fast, is it possible? yes. but then you look at the location of the car seat and all of the other factors together, and that showed us that he could not have. >> investigators noted that coopers' car seat was just inches from the driver's seat, and when they looked at surveillance video from ross's work parking lot they saw this, video of ross backing up before he parked. they were sure ross must have seen cooper when he backed up. >> we wanted to see for ourselves. we're in the same type of car ross harris was driving. we placed the same model of car seat in the same spot cooper was sitting.

if i turn around i can definitely see it. if i use my mirrors to back up, i can't. >> and there was another detail the surveillance video from home depot reveal. ross had gone to lunch with some friends. there he is getting picked up. but look here, nearly an hour later there he is again getting dropped off at his car. he opens the driver's door and throws a box of light bulbs on to the front seat. ross never told detectives about going back to his car in the middle of the day. >> did he lie about going to the car or did he just not disclose that he had gone to the car? >> i think when you look at it in totality he absolutely lied about it. >> investigators were sure ross was hiding something. they believed there was no way he could have opened that door and missed his son in the back seat of the car. >> did you consider the possibility that maybe he really just did throw the light bulbs in there and didn't see cooper? >> absolutely. but when you look at everything else in the case, absolutely not. >> and that everything else

included what investigators uncovered on ross's cellphone. >> there were a whole lot of secrets about to be revealed? >> yes, ma'am. >> coming up -- >> did you engage in sexual acts with him? >> yes, on three different occasions. >> this guy clearly was leading a double life. >> when "dateline" continues. ♪ ♪ protect your pet with the #1 name in flea and tick protection. frontline plus. trusted by vets for nearly 20 years. 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.

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i'm dairy brown. the top stories. the ongoing crisis at the border, president trump continued to stress the importance of maintaining a strong southern border while speaking at a nevada gop convention. thousands of protesters gathered across the country to keep families together rally to protest the immigration policy. the department of homeland security says 522 children that were separated from their families will be reunited with them in the next day or so. now back to dait line. "dateline." welcome back to "dateline."

i'm craig melvin. investigators probing the hot car death of cooper harris discovered video evidence they say proved his father ross would have known cooper was still in the car. now secrets about ross's personal life were about to be revealed. surprising details that could provide a glimpse into a possible motive for murder. here again is andrea canning. >> police were suspicious of ross harris from the moment they met him on that first terrible day. but their next discovery would turn this strange case into an explosive one. police seized his phone and computers, and that's when they found the photos and texts. >> this guy clearly was leading a double life. >> investigators found a sordid stash of sexually explicit online chats and texts between ross and a number of women, one as young as 15.

and what's more, some of the sexual chats happened on the very day cooper died. >> he was communicating with a woman ten minutes before he left with cooper? >> right. and we were able to determine that he had been messaging at least six different women throughout that day, sending pictures of himself, asking for photographs. >> prosecutors believed ross harris was in the grip of an escalating obsession with sex and they came to an awful conclusion. that ross wanted so badly to be rid of the constraints of family and fatherhood he decided to kill his own child. >> does being a creep with women make him a child killer? >> absolutely not. in this case though it showed us the extent to which he was living this other life. it showed us how it had overtaken in his life what was important to him. >> so they threw the book at him. ross was indicted for malice murder, the first person ever accused of using a hot car to intentionally kill a child.

the case became a media sensation with more revelations. investigators said ross had done internet research on hot car death and even visited an online forum for people interested in living a child-free life. a monstrous portrait was emerging, but even after weighing all of the allegations ross's friends were still convinced he never meant to hurt cooper. >> did you ever hear ross get frustrated with cooper? >> no. >> treat him like he was a burden at times? >> no, no. >> you know, there are times when kids can get on our nerves. >> uh-huh. no, no, there are times when you definitely need a break, okay, but he -- he loved that boy. >> ross harris' family enlisted the help of defense attorney mat tox kilgore and his team. >> the entire case was a house of cards. we felt that despite public sentiment and despite the

bravado and of the state and the charges, we felt extremely confident that house of cards was going to collapse in trial. >> in october 2016, more than two years after the death of his son, ross harris went on trial for murder. >> death. deception. and a double life. >> chuck boring, the lead prosecutor, told the jury why ross's story had never added up. that chick-fil-a video showed cooper wide away. that drive was too short to forget a toddler. the car seat was just inches behind ross. and at ross's office there was a photo of cooper and a gift from cooper. he even sent a text to leanna in the afternoon about cooper. when you getting my buddy, it said. none of that jogged his memory? >> there was just cue after cue after cue, that if he had actually forgotten would have triggered something.

>> and then the prosecution showed what it believed was powerful evidence that ross had to have known that cooper was still in the back seat, that video of ross returning to the car. >> why would ross harris return to the scene of the crime? >> we know first of all doing this job enough people do return to the scene of their crime. once he went into the car he realized either this child was still alive or this child was dead and he couldn't take what he had done and he threw the light bulbs. >> and prosecutors dissected ross's behavior later that day. witnesses at the scene testified his reactions were off. >> did he ever ask to be with the child, ask to hold the child or anything like that? >> no, sir, not that i recollect. >> prosecutors pointed out that when ross got into the patrol car he complained about, of all things, the heat in the back seat. >> feels like i'm -- >> and while jurors heard that ross seemed disconnected from his son's death, they also

heard he was obsessed with the sexual contacts he had made outside his marriage. a parade of women took the stand. a woman ross said he was in love with, another woman he met at his home. >> we had sex. >> and a prostitute. >> did you actually engage in sexual acts with him back in may. >> yes, on three different occasions. >> this is one of the six women ross was communicating with on the day he says he forgot about cooper. >> at 5:26 a.m., within 17 seconds of your messages, did he respond? >> he did. >> did you have to consider the fact maybe all of these women were causing a distraction for ross which led to what happened versus that the women were actually a motive? >> no, absolutely. but when you look closely at the content of the messages and what's going back and forth, and specifically you are trying to prove to a jury this person had the intent in his mind to kill a child, you have to get to know that person. you have to get to know what they're made of.

>> and prosecutors say one message in particular said it all. just minutes before ross strapped cooper into his car seat for the last time, he messaged a woman on an anonymous app called "whisper." he typed this. i love my son and all, but we both need escapes. >> honestly, it sent chills down our spines knowing we were in the head of a murderer. >> nonsense according to the defense. >> if he is in the throes of committing a heinous murder, is he really going to announce that by texting it through this application right in the middle of doing it? >> ross's defense team says the entire case against him was outrageous, built on evidence that was twisted by prosecutors to make him look like a killer. they say that message about escape, for instance, was about hanging out with friends, not killing his son. >> if you take that one message in isolation, you can make it

mean all kinds can of things. >> another case in point, that child-free website ross supposedly visited, he actually found it repulsive. >> the link was sent to him by a friend in jest. ross goes to the link, looks at it and he responded, grossness. >> and the defense says there was more misinformation released early on, like that story about ross researching hot car deaths. ross had clicked on one video posted on a popular website about pets in hot cars, but the defense said that was hardly research. a computer expert testified ross never actively searched for information on hot car deaths. >> i didn't see him searching for anything at any point in time that would have been how to kill a child within the car or hot car deaths or anything like that. >> as far as his return to the car that day, the defense says ross had no idea his son was in

the back seat, never even glanced inside as he tossed the light bulbs on to the front seat. look at this angle of the video. >> the proof was his head never got below the roof of that car. the proof showed that he was turning in the other direction. >> but what about those reminders during the day. >> shouldn't one of those have triggered his mind to say, wait, cooper, where's cooper? >> i think that's a fair question to ask. if ross had forgotten that he had a son, seeing a picture of cooper would have reminded him he had a son. he didn't forget he had a son. once ross slipped into his workday, he had every reason to believe that cooper was at the daycare. >> as for those witnesses who said ross seemed detached, they didn't know him, the defense argued, so they called people who did like his friend billy. >> in my opinion, just was incredibly loving and doting. >> a colleague from home depot.

>> when cooper was born, he was -- that's all he would talk about. >> even prosecution witnesses wound up vouching for ross as a good dad. a teacher from cooper's daycare. >> he would just spend quality time with him, interacting with him during the activities. >> and some of those women who testified for the prosecution about sexting with ross, even they agreed he seemed to love his kid. >> what would he say about his son? >> that he was great and that he loved his son. >> he just talked about how much he loved him and how he would never do anything to hurt him and that kind of thing. >> but the woman who should have known ross harris best was about to take the stand. she had something to say about the man who betrayed her and left her son to die, and it may be the last thing you'd expect to hear. >> coming up -- >> cooper was the sweetest little boy. >> heartache laid bear. cooper's mom tells her story. >> i just kind of went into a panic.

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nexgard. the vet's #1 choice. leanna harris had lost so much, her child and her life as she had known it. by the time ross went on trial leanna had heard all of the revelations she could stand and she had divorced him. >> if anyone had a reason to hate ross, to be angry at ross, to not get up on that witness stand for ross, it is her. >> right. >> but yet she did.

>> because she believes 100% that it was not intentional. >> so there she was in court, not condemning ross but defending him. >> tell me a little bit about cooper. >> cooper was the sweetest little boy. he had so much life in him. he was everything to me. >> and everything to ross too, she testified, as the jury watched family videos of father and son. >> what are we looking at there? >> that's them in our bed, and they would just -- that's kind of a little game that they would play. >> leanna said ross was the kind of dad who always played at the park. >> you do it. go. >> he made goofy videos of his

son at snack time. >> you want it? >> yeah! >> ross loved his little boy? >> yes, he did, very much. >> did you -- did you ever see ross express anger or hatred or malice towards his son, ever? >> no, never. >> then came that terrible day. the courtroom was silent as leanna described arriving at cooper's daycare and being told he wasn't there. >> she said, he didn't come today. and i just kind of -- i just kind of went into a panic. i didn't -- i didn't know what to do. i was just -- it didn't make sense. cooper was supposed to be at daycare. i was supposed to be the one to pick him up. it didn't make sense. the only thing that made sense to me based on everything that i

knew that day, ross was -- ross must have left him in the car. >> it made sense because she knew ross so well. he could be forgetful. >> when she saw the video, she recognized that guy, too. the overly social guy chatting away. >> he would just talk to everybody. very outgoing, very vocal. he didn't -- he never met a stranger. >> but leanna also told the jury how ross looked when she first saw him at the police station. she says he was in terrible pain. >> it was very difficult to see him like that. >> this was the true face of ross' grief and guilt, the defense said. >> and leanna explained to the jury why she asked ross that question that made investigators so suspicious.

>> did you say too much? >> i couldn't understand what was happening. i didn't understand why he was being charged, and the only thing that i could think in my head was what -- what did you say. and so those words came out. >> as for that prosecution theory that ross had wanted to escape his family for his secret life, leanna said it wasn't true. she had known for years that ross had a problem. >> i came home from work one day and he told me that he had a problem with pornography. two years after that probably i found a message on his phone that, i guess you would describe it as sexting. she says they worked hard to save the marriage. if ross had wanted out all he had to do was ask. >> i just very bluntly one night said, do you want a divorce?

i mean if you want a divorce, you can have it. i will give it to you if that's what you want. and i believe his answer back to me was, that's the last thing i want. >> prosecutors told us there was no evidence leanna knew what her husband was supposedly planning, and when she cross-examined her they suggested she didn't know her husband at all. >> do you agree there's a whole part of his life that you had no clue about? >> i would agree e that i did not know the depth. >> have you read the text messages he sent to the other women? >> no. i have no reason to have read them. >> okay. so, if he's saying foul things to a 15-year-old girl, you wouldn't think that was something different than the way he portrayed himself to you? >> i think it's horrible. >> the prosecutor pointed out that ross lied to her all the time. one example -- >> did you know there was an

afternoon he actually called a prostitute and went to have sex with her instead of being in your home? >> i didn't know that. >> humiliating as it was, she stuck it out for nearly two days of testimony. >> that woman had every reason in the world to hate ross harris. and despite all of that, despite all of that, she was willing to come testify for him because she knew what the truth was. >> and then, in his final question to leanna, ross' attorney wanted to make something clear. leanna was there for one reason only. she believed that what happened to cooper was a mistake, not a crime. and now she was ready to walk away. >> how do you feel about your ex-husband? >> he ruined my life. he destroyed my life. i'm humiliated, i may never trust anybody again the way that i did. if i never see him again after this day, that's fine.

>> nothing further, judge. coming up -- >> ross harris is an innocent man. >> the jury has its verdict. when "dateline" continues. o power your wellness. new emergen-c probiotics plus. purposeful probiotics to help boost your microbiome, plus vitamin c to support your natural immune defenses. new emergen-c probiotics plus. emerge and see. new emergen-c probiotics plus. ♪ protect your pet with the #1 name in flea and tick protection. frontline plus. trusted by vets for nearly 20 years. find thenah.ote yet? honey look, your old portable cd player.

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welcome back. leanna ross testified that her husband ross did not mean to kill their toddler, cooper. but the prosecution presented a

compelling case pointing to his guilt. what would the jury decide? here with the conclusion to our story is andrea king. >> ross harris, the man whose ex-wife said never met a stranger was about to have his future decided by 12 of them. how are you all feeling as the jury went out to deliberate? >> i didn't think there was any chance of them coming back with guilty on anything that had to do with cooper. >> ross' cousin kate said nothing she had seen in trial swayed her belief in ross' innocence. >> you can hold a gun to my head and tell me that i had to say that ross hurt cooper on purpose and it will never come out of my mouth. it will never come out of my mouth. >> ross' best friend billy was equally confident. >> the prosecution did not do well at all. they did not prove the motive. they didn't get close to it. in fact, i feel like their witnesses could have been defense witnesses. >> the jury took its time to deliberate the charges.

not only multimillion counts of child cruelty and murder, but ross faced charges with explicitly exchanging with a minor. one day passed, then two, then on the fourth day word came, a verdict. >> we the jury find count one, we find the defendant guilty. >> guilty on all counts. i'm sure you will never forget that moment. >> it's ludicrous. it's insanity. >> what would you say to the jury? >> i'm disappointed and don't feel like they did their job. >> we wanted to know how the jury reached their decision. none of the jurors would speak to us on camera, but they said they played close attention to the video showing ross harris returning to his car at lunchtime. in fact, they wanted to re-examine it during deliberations. and the juror told us in his heart of hearts he says ross

harris meant to kill his son. the prosecution says the jury got it completely right. but hearing the word guilty was no cause for celebration. >> what i want to hear announced is -- you know, to bring cooper back. you can't get that from it. >> three weeks later, a judge sentenced ross harris to life in prison. >> the sentence in the court is life to serve confinement without parole. >> reporter: his defense sentenced an appeal arguing that they never should have allowed all the testimony about sex into the murder trial. and the defense says inaccurate information released early on about ross' computer searches made it impossible for him to get a fair trial. >> our personal belief, not lawyer talk, our personal belief in knowing ross, in knowing this case better than anyone in the world, ross harris is an innocent man. >> are you going to keep

fighting? >> this case is far from over. >> having seen this, he says he has complete faith in the verdict. >> i believe the verdict will be affirmed. >> but ross harris' family and friends think this conviction will make it worse for parents who make a terrible mistake. >> this sets the precedent that anybody who does this is a monster. and that is not the case. this really can happen to anyone. >> cooper? >> the family may never stop grieving for the little boy who just learned to say his dad's name, loved trucks and loved to smile. what does leanna want cooper's legacy to be? >> that he was loved.

he was very loved. by everyone he knew. especially his parents. >> that's all for this edition of "dateline." i'm craig melvin. thanks for batwatching. good morning. i'm dara brown in new york at msnbc world headquarters. it is 7:00 in the east, 4:00 out west, and here's what is happening. president trump doubled down on his push for tough borders despite the outrage over family separations. >> even if they saw any weakness, they will come by the millions. we have to have strong borders. this morning, whether immigration will be a winning issue for republicans in november. plus, 86-sarah huckabee sanders. a little restaurant is in the