two innocents riding their bikes through a park, on a sunny day. >> that's all for this edition of "dateline." i'm natalie"dateline." thank you for watching. i'm craig melvin. >> i'm natalie morales. >> and this is "dateline." i did not want to believe it. my sister's dead. and i just -- sorry. just kind of fell apart. >> inside a silent home, an eerie scene. water pouring through the rooms. >> you heard the water running? >> yes. it was just like gushing. i saw her in the bathtub. >> facedown? >> right. >> drowned? no. >> she was badly beaten. lots of bruising. >> but clues would be hard to

come by. >> detective sanchez claims that by leaving her in the water, that washed away any dna evidence. >> i thought it was over. she was just dead, and nothing was going to be done. >> not if this family could help it. >> we started looking for what happened. there was still water in the tub. we pulled the drain and saw black scuff marks. >> a case that would see a key suspect skip town. >> i was like, wow, he's going to alaska. >> that's exactly what people do. they get in trouble, they take off. >> and unearth dark deeds from the past. >> she would wake up, and he'd be standing over her watching her. >> that's creepy. >> sinister stories. >> she told me that he was following her. >> yet justice was anything but certain. >> you want that smoking gun, and there's just not one. ♪ >> hello and welcome to "dateline." cassie fairington was building a

new life in the tiny desert town she called home. the single mom head two beautifl kids, a doting boyfriend, and an exciting new job. that future washed away when cassie was found dead in her bathtub. unsatisfied with the police investigation, cassie's parents said out to solve this mystery and would stop tat nothing to gt justice for their daughter. here is keith morrison with "suspicion in silver city." ♪ >> out in the middle of new mexico, hours of desert highway from better-known haunts like santa fe, is an old mining town called silver city. and such an unusual place it is. quirky would be a good word. >> there's a lot of history in silver city. >> a vast era desert one way out of town, lush green mountains

the other. four sixth generation ranchies and silver miners co-exist with artists and hippies and wide-eyed newcomers. as we say, quirky. >> just lots of different perspectives which is always fascinating. >> but of course this is not a travel log, no. no, this is about what happened here or, more precisely, what happened in there. inside that little house to her. >> she was beaten from head to toe. she had bruises from top of her head down to her feet. >> her name was cassie farrington, and what was done to her in the bathtub of her own house was dreadful. >> she's in the bathtub, and she's -- i can't even -- she's

stiff. >> it was also for a very long time an unsolved mystery. cassie brooks was her name then. her mom and dad, darlene and chuck. >> she was very, very outgoing. driven, motivated. >> from when she was a little kid? >> yes, from the time she was little. straight as, perfect grades. she worked hard. >> cassie seemed to be good at pretty much everything. >> she lettered in five sports her senior year, too. and she was in the national honor society, future business leaders of america. >> what sports did she play? >> volleyball, basketball, softball, track, and palms. >> you must have amazed. >> she never quit. i would have to make her take down time. take a weekend, a saturday, and i would tell her, you're not doing anything, you're going to town with me. i would add, i have this -- time for a break.

she just pushed herself so hard. >> she aced high school in just three years, announced to her family that she was going to be a doctor. and then she was 16 years old, she tried to hide what happened. but of course couldn't. she was pregnant. med school was not going to happen. and then, said cassie's siblings, elizabeth and bo o, events kind of whizzed by. >> she had a baby, got out of the hospital, graduated high school, got married, and moved out in one month. >> wow. >> yeah. >> super fast. >> but the marriage didn't last. by 22, cassie, now cassie farrington, was on her own in silver city with two small kids, working as a nurse. in fact, she moved into a house owned by one of her nursing professors, this woman, charnel

lee. was she a got tenant? >> oh, yes, like the best. >> all the time -- >> always. yeah. she was awesome. >> just around that time, charnel was heading to a breakup with her husband billy. billy was also a nurse. maybe a mentor of sorts to cassie. and he seemed to be very fond of her. saw her a lot at work, around the house. then pretty soon, a serious boyfriend came along for cassie -- david berry. >> he was wonderful with the children, and that was something that she really liked about him. >> cassie's friend and co-worker, mary flores -- >> they had a relationship that was fun. they were just building a life together. >> especially on the morning. march 24th, 2014. something billy lee had been trying to arrange for her came through. >> she had just been notified by

billy lee that she was getting off of the medsurg floor, going to the e.r., the job she wanted. >> cassy had just finished her graveyard shift at this silver city hospital when she called her mom to tell her the news. that was the plum job. the one she always wanted. >> yes. >> then she went to get the kids off to school and have a nap before meeting her friend mary again later. >> i had heard that the shift was particularly difficult. so i texted her and told her to go home and get some rest. and then when she got up, to get the kids from school, we could all -- they could come by. we'd go get ice cream or something. >> the afternoon came -- no cassie. >> i understand, you know, you have kids and who knows -- a million things could have come up. >> and when cassie's parents got a call from their grandson's school to say she didn't show to pick him up, they weren't really worried. >> i was hoping that she'd just slept through her phone because

she'd worked graveyards the night before at the hospital. >> but eventually a request to charnel, the landlord, could she check on cassie, please. >> so i drove from my house up at the hill. >> up there -- >> down this way and up here to go in and check on her through the back door. >> which is where she noticed the strangest thing. >> i looked at the door, and there was water, you could see through the door, there was water rolling out. i knocked. >> was it coming out under the door -- >> no. rolling out into the kitchen right there. >> weird. that would be very strange. >> yeah, it was very strange. and then i -- as soon as i saw that and i knocked, and i called for cassie. and nothing happened. and then so i had to go back up to the other house to get the key. >> and then just came right back here. >> yeah. then i unlocked the door. >> dread gripped her then, something bad in there. and where was cassie?

>> a home full of water, an ominous sight. but nothing compared to what came next. coming up -- >> you're a nurse. you've seen lots of things. >> yeah. >> but that can't have been easy. >> no.

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>> reporter: something was clearly wrong inside this small home on the outskirts of silver city, new mexico. >> very strange.

>> reporter: charnelle lee, checking on her tenant, cassy farrington, opened the back door and was confronted by water everywhere. and you heard the water running? >> yes. it was just, like, gushing. >> reporter: coming from? >> the bathtub. >> reporter: so she ran to the master bathroom, intending to turn off the water. and there she was. >> i saw her in the bathtub. it was like i've never seen anything like it. it was heaped up, and the waves were just, like -- >> reporter: that's a deep -- big -- >> -- cresting. >> reporter: -- deep bathtub, too. >> yeah, it was, like, cresting. and she was on the top. >> reporter: oh. >> and she was -- >> reporter: in the water. >> yeah. she was upside down. and it was -- >> reporter: face down. >> right. right. >> reporter: i mean, you're a nurse. you've seen lots of things. >> yeah. >> reporter: but that can't have been easy. >> no. well, at the time, you know, you're just in like emergency mode, you know? you just -- you don't even stop to think. you -- and so i just went and grabbed her and pulled her over to here and turned her over to see if there was something i could do to help her.

i mean, it was kind of horrifying because she was still in her nursing scrubs. and then i checked to see if she had a pulse an she didn't. >> reporter: nothing to do now but call 911. >> she's been in the bathtub and i -- i can't even do cpr. she's stiff. >> okay, so she's unresponsive right now. >> she's dead. >> reporter: as charnelle talked to the 911 dispatcher, she turned off the faucet and -- >> oh, my god, why is there water running everywhere? that's weird. i heard water running in the extra bathroom. >> reporter: at the other end of the house. >> yes. >> reporter: so charnelle ran back there and discovered water running in the other bathtub, too. no flooding. that drain was unplugged. and when she turned off the water, charnelle noticed that the towel rack was broken. this bit right up here. >> yes. >> reporter: it was just sort of yanked off the wall then, huh? >> totally yanked off the wall. >> reporter: huh. >> and then that's her --

>> reporter: leaving a gaping hole or something, right? >> right, yes. >> reporter: by then the grant county sheriff deputies were arriving, and they asked charnelle to leave. what'd you see? >> i saw water on the ground on the north side that had been coming out of the trailer. it was still dripping, in fact. >> reporter: lieutenant ray tavizon was the supervising chief deputy. while his lead detective, jose sanchez, took charge of the scene and the investigation, tavizon had a look around. any sign of forced entry anywhere? >> no, no. >> reporter: no sort of footprints or tire marks or anything? >> no. the way the ground is, the gravel and stuff, there wasn't any. >> reporter: and inside the house? >> we saw that there had been what looked like maybe a scuffle in that bathroom. >> reporter: what told you that? >> well, there was a broken towel rack -- >> reporter: uh-huh. >> -- laying on the floor. there was a pair of glasses laying on the floor. and then from there, we went to the north end of the trailer. her bed was made.

it hadn't been slept in. her lunchbox, her backpack and her purse were all on the foot of the bed. >> reporter: in other words, this was not a robbery. >> apparently not, no. >> reporter: it didn't look like it. they would have taken that stuff. >> correct. there was a laptop in the bathroom. >> reporter: uh-huh. >> and then she was laying on the floor. and at that point, i went out and called my superiors to inform them what we had. >> reporter: there is no getting over the phone call cassy's parents got then. >> all i remember is she starts screaming, "no!" and then she told me, "they found cassy dead in her home." and i just grabbed my car keys, and we were out the door and gone, headed to silver. >> reporter: what was that drive like? >> it seemed like it took forever, but it was the fastest i'd ever made that trip. >> reporter: what goes through your minds? >> we're just hoping that they're wrong. >> yeah, hoping they were wrong. >> reporter: but they arrived in

time to watch cassy being carried away in a body bag. and then, traumatic as that was, as they stood there, lieutenant tavizon approached them and seemed to say it looked like she'd committed suicide. >> lieutenant tavizon mentioned to you how many times, three times? >> three times in that evening. he brought up suicide and -- and i said she wasn't suicidal. >> reporter: as if, what, he's trying to persuade you that that's what it was? >> yes. >> it wasn't a suggestion that was made. it was a question that was asked. >> reporter: but sitting here, all this time later, lieutenant tavizon told us they must have misunderstood him. you heard that they eventually decided that what you had done was suggest that it was suicide. >> well, yeah. they were -- they were upset because i asked the question. >> reporter: did you think so at the time? >> no. >> reporter: so what did the lieutenant think? >> a young lady just doesn't die, you know, just out of the blue. we consider it a homicide till

we're proven otherwise. >> reporter: sure. of course, there was that other matter that needed proving. who did this? >> coming up, after just a few hours at the house, detectives leave the scene. >> how can you be done with your investigation that quick? >> so the family decides to do a little detecting of its own. >> there was still water in the tub. we pulled the drain. and we saw black scuff marks. >> when "dateline" continues.

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>> reporter: it's a terrible thing to encounter, cop or not. so young. just 23 and a mother of two. but there she was. and what happened to her, as the deputies could clearly see, was close up and intense and murder. did you see any obvious injuries on her body? >> well, there was some bruising on her arms. there was some bruising around her neck. >> reporter: what was less clear, however, was exactly how her death was caused although -- did it leap out at you, though, and say, "somebody beat this girl or strangled her, or something"? >> it was suspicious. very suspicious. >> reporter: the sort of thing that could keep crime scene investigators busy all night. swiping for dna, taking fingerprints, collecting all the bits of evidence.

and yet -- and this was very strange -- after just a few hours, during which they didn't do those things, the deputies left and told cassy's family, "go on in if you want." >> yeah, they released the house. "you can go in." >> and they put their hand to -- at the door, "you can all go in now." >> how can you be done with your investigation that quick? >> reporter: odd. not exactly normal protocol, especially since once people start walking in and out, the scene becomes highly compromised. did you go into the house that day? >> yeah, when -- when they said, "you can go into the house," we went in. >> reporter: they were hoping to find some sign or clue to explain what happened to cassy. but they never imagined they'd find evidence that the deputies just left behind. >> there was still water in the tub, so we pulled the drain. and when we pulled the drain,

then we saw black scuff marks, like, from shoes, rubber. black rubber -- >> reporter: in the tub? >> in the tub. >> reporter: and where did those scuff marks come from? >> from a struggle. >> reporter: they also found cassy's glasses and a hair ribbon near the broken towel rack. no one had bothered to collect them as evidence. so they did. it's so strange to have the family as a kind of csi group. >> yeah. we gathered up the hair with the bobby pin and the ribbon, her glasses. >> reporter: did it seem shocking -- >> we were gathering evidence. >> reporter: -- to you that you were gathering evidence and not -- >> that was -- >> reporter: -- the police? >> -- frustrating. >> yeah. >> reporter: kind of, like, a tell right off the top. this isn't gonna necessarily go well. deputies did return to the house the next day, though, and discovered the carpet in her bedroom was gone. >> billy lee, the landlord, goes in and starts rippin' the carpet up. >> reporter: wait a minute. >> yeah. >> reporter: you've got a guy going in right after, and the first thing he does is rip the carpet out of the master bed -- >> well, it's soaking wet. >> reporter: and that finally seemed to get the attention of

the lead investigator, sergeant sanchez, who by then already had a few reservations about mr. lee. why would he remove the carpet? to get rid of evidence? and what was his relationship with cassy? >> mr. lee told him that he really didn't have any dealings with cassy. then later found out that she had applied for a position in the -- in the emergency room. and billy lee was the one that was helping her. and that's what threw red flags up for -- for sanchez. >> reporter: why? >> well, because he was thinking maybe he was there to try to collect a favor for -- for getting her the job. >> reporter: did cassy reject billy lee and pay a terrible price? a few days after cassy's death, the investigating deputy set out to officially question billy. but billy was gone, had quit his

job and left town, was far, far away in alaska without his wife. >> i was like, "wow, he's going to alaska. maybe sanchez is on to something." >> reporter: but that's exactly what people do. you know, they get in trouble. they take off for alaska or someplace like that, or mexico or something. but for whatever reason, no effort was made to bring billy lee back to silver city for questioning. and investigators quickly turned their attention to another man in cassy's life, her live-in boyfriend, david berry. >> his behavior the first few days after her death was very strange and peculiar to me. >> reporter: how so? >> i, myself, never really saw him shed a tear. but i was suspect of everyone that had any contact with her. i didn't trust anyone. >> reporter: at the funeral cassy's casket was left open to tell the world what was done to her, said her siblings. >> her face was covered in bruises.

her neck was a giant bruise and swollen. her hands were black. >> reporter: but who had done it? for months, all anyone could do was speculate. >> i thought it was over. i thought she was just dead and that was it and nothing was ever gonna be done about it. >> reporter: at the sheriff's office, investigative supervisor tavizon questioned his deputy, sanchez. why hadn't he even dusted for fingerprints? >> he said, no, he said, "it's too clean." to him it wasn't anything that would've been helpful to the investigation. >> reporter: kind of an assumption there, huh? >> well, i guess i would -- that's what you could call it. >> reporter: what's the old expression? to assume makes an ass of you -- >> it makes both -- >> reporter: -- and me. >> reporter: yeah, exactly. so, with zero physical evidence to point to anyone, the case of the murder in the bathtub went cold.

until? until six months later, a particular friend, once suddenly gone, just as suddenly reappeared. time for a pertinent question or two. >> coming up, billy lee back from alaska admitting he and cassy were close. >> we were real good friends. >> but what will he say to this? >> did you inflict any injuries to the victim on march 24th? she wanted a roommate to help with the cooking. but she wanted someone who loves cats. so, we got griswalda. dinner's almost ready. but one thing we could both agree on was getting geico to help with our renters insurance. yeah, switching and saving was really easy! drink it all up. good! could have used a little salt. visit geico.com

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with a saturation level between 96 and 98%. the team is cautiously optimist big his recovery. now back to "dateline." welcome back. in the hours and days after cassie farrington's death, headquarters landlord's husband, billy lee, was raising suspicion. first he tore up the carpet in cassy's home, then skipped town. detectives wondered if billy had something to hide but failed to haul him back for questioning. cassy's family felt the investigation had been boshed, and the search -- botched, and the search for answers was taking a toll. here again, "suspicion in silver city." >> reporter: cassy's parents were in pain, deep endless, about her murder and the long

wait for justice. >> that period of waiting? >> hard. >> very difficult. difficult on us. between us. >> how come? >> i was crying all the time. >> few things eat at a marriage quite like grief. even the best marriages. >> all she wanted to talk about was cassy's case. >> when months went by with no arrest. >> i got to the point where i told her i can't do it anymore. i thought about it, too, but didn't want to talk about it all evening with her. >> reporter: but the topic was unavoidable. any new lead or development had to be discussed. the medical examiner's report, for instance, that didn't come out for four months. when it finally did, it was vague. >> it was homicide by undetermined means. >> reporter: undetermined means? you saw bruises all over her body and apparent strangulation.

>> and they wouldn't classify it as strangulation was the cause of death. multiple mechanisms is what caused the death. >> they knew that if the case went to trial, that vagueness could be a problem, that is if it went to trial because the investigation seemed to be going nowhere. the family found things out like how boyfriend, david, had a solid alibi. so why wasn't he officially cleared? why did darlene seem to be a more active investigator than the deputy. >> she drove me nuts. trying to play crime scene investigator. but it also helped me to push the cops. >> too hard, maybe? >> detective sanchez said i'm tired of mrs. brooks calling me all hours of the night. >> but they kept pushing anyway. >> i asked, well, did you get billy lee down from alaska, have him do his polygraph? he said, yes. >> reporter: now, remember, he

lived on the same property as cassy and was married to her landlord and hours after the murder he ripped out her bedroom carpet and then went to alaska. the question was, why? months after he left, billy returned. >> my name is billy lee, or william actually. >> reporter: and sergeant sanchez had his chance to question him. >> how long did you know cassy? >> i knew her when she was a tech in the emergency room. >> reporter: curiously sanchez did not ask why billy removed the carpet or why he suddenly took off for alaska, but he did ask about the nature of billy's relationship to cassy. >> we were real good friends. we didn't go to bars together and we didn't go fishing together. we didn't do that kind of stuff but we had a working relationship that was pretty close. >> reporter: really? back at the crime scene day of

the murder, he claimed he barely knew her. now they were pretty close. too close? billy told the detective he had an alibi. he and a buddy were out in the country working on his cabin. >> we were working on that roof and when i got the call, we'd been out there for a couple of days. >> reporter: but, of course, as any detective could tell you people lie all the time about alibis. sanchez asked billy to take a polygraph. >> did you inflict any injuries to the victim on march 24th? >> no. >> reporter: the results were inconclusive. not so good for billy and that alibi? it just kind of sat there unchecked. until finally a year later lieutenant tavizon did some checking and confirmed his alibi was absolutely solid, though,

when we tracked him down, he said this -- >> they never did in my mind ever really truly suspect me because i had such an alibi. >> i hate to say it but i've looked at what they were saying. you were their number-one person of interest. at least one investigator's number-one person of interest. >> they never told me that. >> reporter: billy also found any suggestion he was too close to cassy particularly offensive. >> absolutely never even thought in my mind to have had a relationship with cassy. not even a little bit. treated her like a daughter. >> reporter: why take off for alaska after the murder. >> got a lucrative job offer up there so i took it. not even thinking of -- >> reporter: that it would look bad. >> yeah, why would it look bad? >> reporter: he felt the same about the carpet he ripped up in cassy's bedroom. there were some people thought billy took it out because billy didn't want evidence to be found.

>> well, what could of evidence would have been in the carpet more than somewhere else. >> reporter: you knew that question was being asked about you. >> after the fact. >> reporter: yeah. >> yeah, sanchez said, why did you take the carpet? i said, because you released the place and we needed to save the flooring. >> reporter: what about the polygraph? why that inconclusive result? >> i can tell you why, instead of you ever been in the house, i said, yes. and she kind of raised her eyebrows because that was our rental house, of course i been in the house, multiple times. >> reporter: maybe they should have asked cassy's family who didn't for a minute suspect billy lee. they would have told the deputies it was long past time to focus on someone new. and who could that be? the person the family had suspected all along. >> he did it. he killed her. we know he did. coming up, disturbing stories about one of the men in cassy's life. >> she would wake up and he

would be in the dark watching over her. >> then a new theory of the case. >> he said a cop did this. that this had been done by someone who had been trained in police tactics. >> when "dateline" continues. at carvana, no matter what car you buy from us, you get the freedom of a 7-day return policy. this isn't some dealership test drive around the block. it's better. this is seven days to put your carvana car to the test and see if it fits your life. load it up with a week's worth of groceries. take the kiddos out for ice cream. check that it has enough wiggle room in your garage. you get the time to make sure you love it. and on the 6th day, we'll reach out and make sure everything's amazing. if so... excellent. if not, swap it out for another or return it for a refund. it's that simple. because at carvana, your car happiness is what makes us happy. here's to the duers. to all the people who realize they can du more with less asthma thanks to dupixent, the add-on treatment for specific types of moderate-to-severe asthma.

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>> reporter: a dreadful whispered suspicion was making its corrosive way around silver

city, new mexico, that somehow cops were protecting cops. the blue code, they called it. >> at first i didn't wanna believe it, but as time went on, it became more apparent that it seemed that way. >> reporter: why? maybe because the investigation of cassy farrington's murder had been going nowhere for so long, even while the family kept trying to tell the detective, sanchez, that a particular silver city cop killed cassy. but the detective hadn't done a thing about it. >> reporter: he never questioned him? >> huh-uh, and i asked him that. and he said he was trying to eliminate everyone else that could be possibly a suspect, and then he was gonna talk to him. >> reporter: but sanchez's supervisor, lieutenant tavizon had already confirmed billy lee's alibi. boyfriend david's too. >> we know he was at work, he left at 5:00 in the morning to go to work in demning, and all that was verified.

>> reporter: and still nothing happened. so one day months after the murder, the anger cassy's family was feeling boiled over. >> i called the d.a.'s office, asked for a meeting to complain about the sheriff's department. >> reporter: and complain he did. forcefully, said chief deputy district attorney george zsoka. >> people got a little hot under the collar, the sheriff, the undersheriff were there. and lieutenant tavizon was also there. >> reporter: he and the others had to admit that lead detective, jose sanchez, had made mistakes, many mistakes. >> i had no reason to doubt him, but i should have. i should have micromanaged him. >> reporter: so maybe the whispers about some blue code were understandable, said deputy tavizon, just not true. >> we do not protect officers if an officer makes a mistake or commits a crime. we treat them just as we would any other person. >> reporter: the real reason

behind a stalled investigation? >> just, uh, laziness. >> reporter: the decision was swift. sanchez was off the case. and this ranch owner and veteran detective stepped in. >> i came in one day and i was told, "hey, we're going to assign you to the -- to the cassy farrington case." >> reporter: sergeant jess watkins. see what you can find, they told him. >> first thing i did was i sit down, read through all the interviews, read through all the reports. >> reporter: and then he listened as cassy's family told him about the city police officer who had never even been questioned about the murder. >> i knew it was farrington that did it. >> reporter: brad farrington, cassy's estranged husband. when cassy died, the two had been separated for more than a year but were going through a nasty custody battle. >> as soon as we found out she was dead, we all thought it was him.

>> reporter: cassy's family told detective watkins that cassy had been living in fear of brad for years and wasn't shy about saying so. >> he had her convinced he was gonna kill her. >> reporter: watkins listened to their stories. many stories. one, when cassy's mom was right there watching. >> he has her against the wall on her side, but he has her in a headlock. >> reporter: didn't you wanna call the police? >> yes, but i felt like if i did anything, he would hurt her. >> and she would wake up during the night and he'd be in the dark, standing over her, watching her. >> reporter: that's creepy. >> yeah. that is the first time she said, "he's going to kill me." >> reporter: and she really believed this? >> yes. >> reporter: the first time? >> uh-huh. >> reporter: how many times? >> she told me at least three times. >> reporter: and then there was this, what brad did to the kids. binding their hands and feet together, even taping the baby's mouth. cassy told her mom about it, said he called this a game. they were relieved when the

couple finally split. and they liked her new boyfriend, david berry. >> i thought when she moved in with david, that maybe she'd be more safe, could get on with life. >> the kids loved him. >> uh-huh. >> tristan actually started calling him daddy david, which cassy would be like, "you can't call him that. your dad's gonna get mad." >> reporter: and sure enough, said cassy's sister, he did. >> he expressed to cassy that he didn't like it. that the kids better not call him that. >> reporter: he blamed cassy for it. >> yeah. >> reporter: and a few weeks before cassy's death, she told her parents, son tristan came home from a visit with brad utterly terrified. >> they ask him, "what's wrong, tristan?" he says, "daddy said he's gonna kill mommy and david." he was 5 years old. i don't think a 5-year-old makes that up. >> reporter: by then brad was no longer on the police force. and things weren't going so well for him. when sergeant watkins finished

reviewing it all, police reports, his own interviews, what he felt was something like amazement. >> wow. nobody in this world is pointed out as having any reason to want to harm her other than brad. as long as she was alive, cassy had the kids and a new man and a great job. and he was losing everything. >> he no longer was working at the police department. you know, they hadn't reached any agreements on these kids. i think that was his way to take what he could from her. just say, "hey, look. those kids are gonna -- they're not gonna have you." >> reporter: was watkins right? we asked to hear the farrington side of the story from brad or his family or both. we asked multiple times, but they told us they didn't want to be interviewed. anyway, for sergeant watkins, the evidence was too compelling to ignore, especially what came

right out of the autopsy. photos which the detective said to the prosecutor told an unmistakable story. >> he said a cop did this, that this had been done by someone who had been trained in police defensive tactics. >> reporter: what'd you think when you heard that? >> well, i thought, we now have the evidence we need to charge bradley farrington. >> reporter: five weeks after sergeant watkins took over the case and a year and a half after cassy was killed, law enforcement tracked down brad farrington in tucson, arizona, where he had taken the children, and they arrested him and charged him with first degree murder. just one nagging worry. there was no evidence at all to put brad at the murder scene. and without that, odds of conviction weren't good. >> i was scared that he was gonna get off. >> coming up, at trial the defense comes out swinging.

>> it will be clear that other people had access, motive, and ability to complete this crime. >> what will the jury think? >> i was so nervous. i just paced up and down halls, in and out. ♪ wild thing,

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welcome back. when sergeant jess watkins took over the cassy farrington, he

came what her parents believed from day one. cassy's ex-husband brad was the only person who wanted her dead. now he was headed to courts charged with the murder. with no physical evidence tying him to the crime scene, could prosecutors prove it? here's is keith morrison with the conclusion of "suspicion in silver city." >> reporter: it was the day the brooks family feared they'd never see, brad farrington on trial for murdering cassy. >> i never thought we would get this far. >> reporter: too far? the prosecutor's opening argument was a warning to the jury, we don't have a lot. >> no one saw the defendant enter cassy farrington's home. no one saw the defendant strangle her. >> reporter: no. and there was absolutely no evidence from the crime scene to help their case. the prosecution didn't even call the now retired detective jose sanchez as a witness. >> what we were rather brief on was the scene.

>> reporter: that was a weakness actually. >> well, i don't know if i would call it a weakness. but it wasn't a strength. >> reporter: you should be in the diplomatic corps. >> well, there just wasn't anything there that was terribly useful. so we showed the scene so the jury could see, you know, this is where it happened. >> reporter: it was unilluminating. and that was a problem until the prosecutor argued for the right to present hearsay evidence, normally disallowed. and he won. >> brad was being verbally and physically abusive toward her. >> reporter: so one by one, cassy's friends repeated stories cassy told them about her fear of brad. >> there would be times where he -- she felt like he was following her. >> reporter: and then cassy's mom told the jury what she saw when brad was with cassy. >> he had her in a chokehold on the bed.

>> when you say a chokehold, can you describe for us just how he was holding her? >> his arm was up on her neck like this. he had her neck. >> reporter: to frighten? control? darlene wasn't sure. but shortly before she died, said her mom, cassy confessed there was another reason, too. >> he liked to choke her during sex. >> reporter: how did that relate to murder? remember, the medical examiner was vague about the cause of death. but not this guy, dr. michael hunter, chief medical examiner in san francisco. >> we're seeing bleeding within some of the muscles. >> reporter: he made it crystal clear to the jury that cassy's killer strangled her. >> once you see injuries to the neck, petechial hemorrhages, evidence of assault that you can form an opinion. and i have formed an opinion that this represents strangulation. >> reporter: but why should the

jury decide brad did that? >> he was in the academy from january 2006. >> reporter: this is ed reynolds, retired silver city police chief and also, once, brad's police academy instructor. the man who taught him the chokehold. >> when i execute this technique, you pull down. >> reporter: so eerily similar to what darlene demonstrated. >> his arm was up on her neck like this. >> reporter: all of which was interesting, said defense attorney nathan gonzalez, but did not prove that brad was the killer. in fact, he told the jury, they arrested the wrong man. >> it will be clear that other people had access, motive, and ability to complete this crime. >> reporter: but their star witness to drive that point home was none other than retired grant county deputy jose sanchez. and what he said on the stand? oh, my. >> was mr. farrington a suspect in your investigation?

>> not my suspect, no. >> reporter: now that was shocking because sanchez had told cassy's parents that brad was a suspect. >> he believed there was an altercation, a fight and that he killed her and then took her and put her in the other tub. he told us that the day after her death. this is sanchez? >> this is what sanchez said. >> reporter: but now, in court, sanchez told a different story altogether which, if the jury believed it, could undermine the prosecution's entire case. >> i was focused already on -- >> mr. lee. >> mr. lee. >> reporter: mr. billy lee. >> why did you decide to focus on mr. lee? >> there were just too many discrepancies. >> reporter: remember, billy was cleared, had a solid alibi. but now the defense was using sanchez to raise doubt about who the real killer was. >> lot of smoke here but no fire. >> reporter: muddles it up. >> and that, i believe, was the defense strategy, that if you

have enough of that, then the jury won't see through it. >> reporter: the jury retired to consider. >> oh, i was so nervous. i just paced up and down halls, in and out. >> reporter: four hours later, they were called back into court. >> has the jury reached a verdict? >> we have, your honor. >> the defendant shall please rise. we find the defendant, bradley farrington, guilty of first degree murder as charged in -- >> reporter: when they announced their verdict? >> there was a lot of tears, a lot of sighs of relief. one of the deputy attorneys says, "thank you for not giving up. thank you for pushing." and i said, "how could i? it was my little girl." >> reporter: brad farrington was sentenced to life, no parole for at least thirty years. he's filed an appeal. and cassy is but a memory now. and so her parents remember their way through their pain to the good in her life. the kids live with brad's family now.

so chuck and darlene's one hope is to see their grandchildren again. >> they don't allow us to see or talk to 'em. >> reporter: anything you'd want to say to them if you could? >> that we love 'em. >> that their mama loved 'em unconditionally. >> reporter: that's all for this edition of "dateline." i'm natalie morales. thank you for watching. i'm craig melvin. >> and i'm natalie morales. >> and this is "dateline." >> i knew she would never leave her kids in the middle of a hurricane. i always knew it wasn't going to be good. >> crystal was gone, and there were lots of reasons to worry. >> she had numerous lovers, men and women. >> you have both the husband and the boyfriend failing their polys. on the same day. >> what the hell is going on? >> the answer would have to