it, my sister is dead, and i just-- i'm sorry. >> inside a silent home, an eerie scene, water pouring through the rooms. >> you the water? >> yes, it was disgusting. i saw her in the bathtub. >> drowned? no. but clues would be hard to come by. >> detective sanchez claims that by leaving her in the water, that washed away any dna. >> i thought it was just over, there was a dead end for me we would never talk about it. >> not if this family could help it. >> there was still water in the tub, we pulled the drain and saw black scuff marks. >> a case that would see a key suspect skipped town. >> i was like, wow, you're going to alaska? >> and on earth dark deep from the past. >> she would wake up and he would be standing over her. >> sinister stories. >> she told me he was following her. >> but justice was anything but smoking. smoking. cassy farrington was building a new life in the tiny desert hello and welcome to "dateline." cassy farrington was building a new life in the town she called home . the single mom had two kids, a doting boyfriend, and exciting new job, but that future washed away when cassy was found dead in her bathtub. unsatisfied with the police investigation, cassy's parents set out to solve this mystery and would stop at nothing to get 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 santa fe is an old mining town called silver city, and such an unusual place it is. quirky would be a good word. >> there is a lot of history in silver city. >> a vast area of desert, on one side of town and lush greenery in the other. fourth, fifth, sixth generation ranchers and silver miners coexist with art hippies and wide-eyed newcomers. as we say, quirky. >> it is just lots of different perspectives, which is always fascinating. >> but of course, this is not a travel log, no. this is about what happened here, or more precisely, what happened there, inside that little house, to her. >> she was beaten from head to toe. she had bruises from the top of her head, down to her feet. >> her name was cassy farrington , and what was done to her in the bathtub of her own house was dreadful. >> she has been in the bathtub. i can even do cpr. statement it was also for a very long time, an unsolved mystery. cassy brooks was her name then peered her mom and dad, darlene, and chuck. >> she was very, very outgoing, driven, motivated peers >> from the time she was a little kid? >> yes. straight a's all the way through . perfect grades. she lettered in five sports her senior year too. she was in the national honor society, future business leaders of america. >> what sports did she play? >> basketball, softball. she would never quit. i would have to make her take down time. take a weekend on saturday or sunday and told her, okay, you're not doing anything. you're going to town with me. you just pushed herself so hard. >> she aced high school in her three years and announced to her family she was going to be a doctor. and then, she was 16-year-old, she had to tried what happened, but of course couldn't. she was pregnant. med school was not going to happen. then, with cassy's siblings , the events kind of whizzed by peers >> she had a baby, got out of the hospital, graduated high school, got married and moved out in one month peers >> year. statement superfast.>> but the marriage didn't last. by 22, cassy, now cassy 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 peers >> was she a good tenant? >> oh yes. always. she was awesome. >> just around that time, chanel was heading toward a breakout with her husband, billy. he seemed to be very fond of her, saw her a lot, would help with work around the house. pretty soon, a serious boyfriend came around for cassy, david berry. >> he was wonderful with children, that was something she really likes about him. they had a relationship that was fun. they were just building a life together. >> especially on the morning of 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 the med surge lord, going to the er, the job she wanted. >> cassy had just finished the graveyard shift when she called her mom to tell her the news. >> that was the job she always wanted. >> yes. >> and then she went off to school, went home and had a nap . >> i had heard the shift was particularly difficult, so i texted her to go home to get some rest and was she got up to get the kids from school, they could come by and we would go get ice cream or something. >> the afternoon came, no cassy. >> i understand you have kids, who knows, 1 million things could have come up. >> and went cassy 's parents got a call from their grandson's school to say she did not pick him up, they weren't married peers >> i had just hoped she slept through her phone because she had worked graveyard the night before the hospital. >> eventually, the request of the landlord to check on cassy, please peers >> i went my house from the hill, down this way, up here to go in and check on her through the back door. >> which is where she noticed the strangest thing peers >> i looked to the door, there was water, you could see through the door there was just water rolling out and i knocked . >> was it just coming out? >> no, just rolling out to the kitchen right there. it was very strange. as soon as i saw that, i knocked i called for cassy, nothing happened, so i had to go back to the other house to get vicki -- the key, and then i unlocked the door. >> dread ripped her then, something bad in there and where was cassy? >> a home full of water, an ominous site, but nothing compared to what came next. coming up.>> you are a nurse . you have seen lots of things. that can't have been easy. >> no. went "dateline" continues. . you can cuddle and brush that hair off. bounce, it's the sheet. mom! he gave us a break on our car insurance. and he'll look after you two. yep, with flexible payment options. ok, but why is shaq coming too? to show you how it's done. ♪♪ for a great low rate, go with the general. stuck at the dmv, and i think i'm late on my car insurance. good thing the general gives you a break with flexible payment options. let's get you a break while you wait. what is this place? this is our dmvip. vending machine charcuterie? for a great low rate, go with the general. and they're all coming? for a great low rate, those who are still with us, yes. grandpa! what's this? your wings. light 'em up! gentlemen, it's a beautiful... ...day to fly. keith morrison (voiceover): something was clearly wrong inside this small home on the outskirts of silver city, new mexico. ry s something was clearly w inside this small home on the outskirts of silver city, new mexico. >> very strange. >> turned out, lee, checking on her senate, cassy farrington , opened the back door and was confronted by water everywhere. and you hurt the water running? >> yes, it was gushing, coming from the bathtub. >> so she ran to the master bedroom, intending to turn off the water, and there she was. >> i saw her in the bathtub. i did never seen anything like it. it was heaped up. and the waves were cresting and she was on the top. >> in the water? >> yeah. she was upside down. >> face down? >> right. >> and you're a nurse, you have seen lots of things. but that can't have been easy. >> know. at the time, you are just in emergency mode. you don't even stop to think. 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, and she didn't peers >> nothing to do now but call 911.>> and she's been in the bathtub. i can't even do cpr, she's stiff . >> so she's unresponsive right now? >> she's dead! >> as charnelle talked to the 911 dispatcher , she talked to the dispatcher and-- >> oh my god, why is the water running? >> i heard water running in the extra bathroom. >> so, charnelle ran into there and discovered other water running in the other bathroom too. the drain was unplugged. charnelle noticed that the towel rack was broken. totally yanked off the wall? >> totally yanked off the wall. and then, that is her-- >> leaving a gaping hole or something?>> yes. >> by then, the grant county sheriff's deputies arrived and they asked charnelle to leave. >> i thought water in the ground on the north side that had been coming out of the trailer. it was still dripping, in fact. >> lieutenant was the supervising chief deputy. while his lead detective, jose sanchez, took charge of the scene and investigation, tavizon took a look around. >> no tire marks or anything like that? >> no. >> no sort of footprints or tire marks or anything? >> no, the way the ground is, the gravel was stiff. >> we saw what looked like a scuffle in the bathroom. >> was told you that? >> there was a broken towel rack on the floor, a pair of glasses on the floor and from there, we went to the north end of the trailer. her bed was made, had not been slept in here at her lunchbox, backpack, and purse were all on the foot of the bed. >> in other words, this was not a robbery? >> he did not look like it. >> they would have taken that stuff. >> there was a laptop in the bathroom and she was laying on the floor. at that point, i went out and called my superiors to inform them what we had. >> there is no getting over the phone call cassy's parents got then. >> all i remember, she started screaming. then, she told me they felt cassy dead in her home weird i just grabbed my car keys and we were out the door and gone, headed to silver. >> what was that drive like? >> it seemed like it took forever, but that was the fastest i had ever made that trip. >> what goes through your mind? we're just hoping they were wrong. >> yeah, hoping they were wrong . >> but they arrived in time to watch cassy being carried away in a body bag. and then, dramatic as that was, as they stood there, lieutenant tavizon approached them and seemed to say to me it looked like she had taken her own life. >> lieutenant tavizon mentioned to you how many times, three times ? >> three times in that evening. he brought up to preside and i said, she wasn't suicidal. >> as if he was trying to persuade you? >> it wasn't a suggestion that was made, it was a question that was asked. >> but sitting here, all this time later, lieutenant tavizon told us they must have on misunderstood him. >> you heard that they eventually decided that what you had done was suggest that it was was i? >> well, yes. all i had done was asked the question. the young lady just does not die out of the blue we consider a homicide until we are proven otherwise. >> 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 peers >> there was still water in the drain, we pulled the drain and there were black scuff marks. went "dateline" continues. . that's better. and that. even this. dupixent is an add-on treatment for specific types of moderate-to-severe asthma. it works with your asthma medicine to help improve lung function. that's pretty good! dupixent is not for sudden breathing problems. it's proven to help prevent asthma attacks. it can reduce or even eliminate oral steroids. and doesn't that make things better? dupixent can cause allergic reactions that can be severe. tell your doctor right away if you have rash, chest pain, worsening shortness of breath, tingling or numbness in your limbs. tell your doctor about new or worsening joint aches and pain or a parasitic infection. don't change or stop asthma medicines including steroids, without talking to your doctor. when you can get more out of your lungs, you can du more with less asthma. and isn't that better? ask your doctor about dupixent, the most prescribed biologic in asthma. ask your doctor about dupixent, keith morrison (voiceover): it's a terrible thing to encounter, cop or not. is 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? >> there was some bruising on her arms, there was some bruising around her neck. >> what was left clear, however, was exactly how her death was caused. although-- >> did it leap out at you and say, somebody beat this girl strangled her? >> it was very suspicious, very suspicious. >> the sort of thing that could keep crime scene investigators busy all night, swiping for dna, taking fingerprints, collecting all the bits of evidence come and yet, this was very strange. after just a few hours during which they did not do those things, the deputies left and told cassy's family, go on it if you want. >> yeah, they released the house . you can go on in. >> and they put their hand at the door, you can go in now. >> how can you be done with your investigation that quick? >> odd. not exactly normal protocol, especially since once people start walking in and out, the scene becomes highly compromised. >> did you go in the house that day? >> yeah, when they said you can go in the house, we went in. >> they were hoping to find some sign or clue to explain what happened to cassy , but they never imagined they would find evidence that the deputies just left behind. >> there was still water in the tub, so we pulled the drain. when we pulled the drain, we saw black scuff marks collect from shoes, black rubber shoes, in the tub. >> and where did those go scuff marks come from? >> from a struggle. >> 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 the family did. >> it is strange to have the family as a kind of csi. was it shocking to you that you were gathering evidence? >> it was frustrating. >> kind of like a tilt right off the top, this is not necessarily going to go anywhere. >> 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 ripping the carpet up. >> wait a minute? you've got a guy going in right after the first thing he does is start ripping the carpet out? >> it was soaking wet. >> that gets 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 them, he really did not have any dealings with cassy, and later found out she had applied or a position in the emergency room and billy lee was the one that was helping her. that is what blue red flags up for sanchez here it's >> why?>> because he was thinking, maybe he was there to try to collect a favor for getting her the job. >> did cassy reject billy lee and pay for terrible crimes? >> the investigator set out to officially interrogate billy, but billy was gone. had quit his job, left town, was far, far away in alaska, without his wife. >> i was like, wow. he is going to alaska. maybe sanchez is onto something. >> that is exactly what people do, they get in trouble and take off to alaska, or someplace, mexico or something. >> but, for whatever reason, no effort was made to bring delete 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, peculiar to me. i, myself, never saw him shed a tear. i was suspect with everyone that had any contact with her. i didn't trust anyone. >> 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. >> 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 going to be done about it. >> at the sheriff's office, investigative supervisor tavizon questioned his deputy, sanchez. why hadn't he even dusted for fingerprints? >> he said, no it's too clean. to him, it's nothing that would have been helpful to the investigation. >> kind of an assumption there? >> well, i guess that's what you could call it. >> was the old expression, to assume makes an-- >> yes, exactly. >> so, 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, was 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? >> when "dateline" continues . . with its diamond weave texture, charmin ultra strong cleans better with fewer sheets and less effort. enjoy the go with charmin. my moderate to severe plaque psoriasis held me back... now with skyrizi, i'm all in with clearer skin. ♪ things are getting clearer...♪ ( ♪♪ ) ♪ i feel free... ♪ ♪ to bear my skin, yeah that's all me. ♪ ♪ nothing is everything ♪ ( ♪♪) with skyrizi, 3 out of 4 people achieved 90% clearer skin at 4 months. and most people were clearer even at 5 years. skyrizi is just 4 doses a year, after 2 starter doses. serious allergic reactions... ...and an increased risk of infections... ...or a lower ability to fight them may occur. tell your doctor if you have an infection or symptoms,... ...had a vaccine, or plan to. ♪ nothing and me go hand-in-hand, ♪ ♪ nothing on my skin, that's my new plan. ♪ ♪ nothing is everything ♪ now's the time,... ...ask your doctor about skyrizi,... ...the number one... ...dermatologist-prescribed biologic in psoriasis. learn how abbvie could help you save. 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[ chuckling ] ♪ ♪ chef's kiss. i richard louis with a news update. a fundraiser has been canceled due to safety concerns. the republican chair hosting that been said, they received numerous threats following revelations-- revelations in a new book that she had killed her daughter. retreat at mar-a-lago this weekend for rnc. former senator marco rubio are among those mingling with voters and donald trump as he tries to narrow down the field for his running mate. now, back to "dateline." welcome back to "dateline." i am andrea canning. in the hours and days after cassy farrington's death, her landlord's husband, billy lee, was raising suspicion . first, you tore up the carpet in cassy's home, and that he 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 botched and the search for answers was taking a toll. here again is chris morrison with "suspicion in silver city." cassy's parents, were in deep pain, serious pain. about cassy's murder, of course, but also about the long wait for justice. >> the period of waiting, very difficult. very difficult on us, coming between us. >> how come? it's >> i was gone all the time. >> few things it at marriages, kind of like grief. when months went by with no arrest-- >> i finally got to the point where i just told her, i can't do this anymore. i thought about it too, but i did not want to talk about it all evening with her. >> the topic was unavoidable. any new lead or development had to be discussed here at the medical examiner's report, for instance, that did not come out for 4 months. and when it finally did, it was vague. >> it was homicide by undetermined means. >> undetermined means? you saw bruises all over her body at apparent strangulation? >> and they wouldn't classify it as strangulation as the cause of death. multiple mechanisms, is what caused the death. >> they knew that if the case ever 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 about how boyfriend, david, had a solid alibi. why wasn't he officially cleared? why did darlene seem to be a more active investigator that a 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, you know, i am tired of mrs. brooks calling me all hours of the night. >> but they kept pushing anyway. >> i asked, did you get billy lee down here from alaska and have him do his polygraph? he said, yes. >> remember, billy lee lived on the same property as cassy, and was married to her landlord and hours after the murder, he ripped out cassy's room carpet and then for alaska. the question was, why? >> months after he left, billy returned. sergeant sanchez finally had his chance to question him it's >> how long have you known cassy? >> i knew cassy when she was a tech in the emergency room. >> curiously, sanchez did not ask billy why he removed the carpet or why you suddenly took off for alaska, but he did ask about the nature of billy's relationship with cassy. >> we were really good friends. we didn't go to bars together, we didn't go fishing together, we didn't do that kind of stuff , but we had a working relationship that was pretty close. >> really? back at the crime scene, the day of the murder, at least as sanchez told his supervisor, billy claimed to barely know cassy, 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 when i got the call. we'd been out there for a couple of days. >> but of course, as any detective could tell you, people lie all the time about alibis. sanchez asked billy to take a polygraph. >> do you inflict any injuries to the victim on march 24th? >> no. >> the results were inconclusive, not so good for billy. and that alibi, just kind of sat there, unchecked, until finally, a year later, lieutenant tavizon himself did some checking and confirmed that billy's alibi was absolutely solid, although when we tracked him down, he said this. >> net they never did in my mind ever truly suspect me because i had such an alibi. >> i hate to say it, but i have looked at what they were saying, you were there number one person of interest, at least one investigator's number one person of interest. >> they never told me that. >> billy never found any suggestion he was too close to cassy particularly offensive. >> absolutely never even a thought in my mind i had a relationship with cassy . not even a little bit. i treated her like a daughter. >> so why take off for alaska after the murder? >> i had a lucrative job offer out there, so i took it, not even thinking. why would it look bad? it's >> he felt the same about the carpet he ripped up in cassy's bedroom. >> there were some people that thought, billy took that out because they do not want evidenced to be found. >> what kind of evidence would be found there that was it somewhere else? after the fact. now, sanchez says, why did you take the carpet? i said, because we released the place and i needed to save the flooring. >> what about the polygraph? why that inconclusive results? >> i can tell you why. they said have you ever been in the house i said, yes. as she raised her eyebrows with that happened. that was our rental house, course i had been in the house, multiple times. >> maybe they should have asked cassy's family, who did not for a minute suspect billy lee. they would have told the deputies it was long past time to focus on someone new. 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 standing , watching over her. >> that is creepy. >> and then, a new theory in the case. >> he said, a cop did this. this had been done by someone trained in police tactics. >> when "dateline" continues . . , all hike, and all night. secret whole body deodorant. 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>> no. and i asked him that. he said, he was trained to eliminate everyone else that could possibly be a suspect and then he would talk to him. >> sanchez's supervisor, lieutenant tavizon, had already confirmed billy lee's alibi, boyfriend, david's too. >> we know he was at work. he worked-- left at five like in the morning to go to work and that had been verified. >> and still nothing. months after the murder, the anger cassy's family was feeling boiled over. >> i called the das office and asked for a meeting to complain about the sheriff's office. >> and complained he did come up forcefully said then district attorney. >> people got a little hot under the collar. the sheriff, the undersheriff were there, and lieutenant tavizon was also there. >> 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. >> maybe the whispers about some blue code were understandable to me--, said deputy tavizon. >> we do not protect officers, even if an officer makes a mistake, or commits a crime, we treat them like we would any other. >> the real reason behind the stalled investigation? >> just laziness. >> the decision was swift, sanchez was off the case. this ranch owner and veteran detective stepped in. >> i came in one day and i was told, hey, we are going to assign you to the cassy farrington case. >> sergeant jess watkins, see what you can find, they told him. >> the first thing i did was sit down, read through all the interviews read through all the reports. and that he listened as cassy's family told him about the city police officer who had never been questioned about the murder . >> i knew it was farrington that had did it. >> brand farrington, cassy's estranged husband. when cassy died, the two had been separated for more than a year. there were going through a nasty custody battle. >> as soon as we found out she was dead, we all thought it was him. >> cassy 's told watkins that cassy had been living in fear for years and was not shy about saying so. >> she was afraid of him. >> they listened to many stories, one when cassy's mother was right there watching him. >> he had her against the wall he had her in the headlock. >> didn't you want to the police? >> yes, but i felt that if i did, he would hurt her when we would not be there. >> and she would wake up in the dark and he would be standing over her while she was sleeping. >> that was the first time. >> the first time? how many times? it's >> she told me at least three times. >> and then that was what brad did to the kids, binding their hands and feet together, even taping the baby's mouth. cassy told her mom about it and said he called it a game. they were relieved when the couple split and he liked-- they liked her new boyfriend, david. >> i thought when she moved in with david, she could be more safe and get on with life. >> the kids loved him and actually started calling him daddy david. and cassy would be like, you can't call him that, your dad will get mad. >> and sure enough , said cassy's sister, he did. >> he blamed cassy for it? >> yeah. >> and a few weeks before cassy's death, she told her parents, son tristan cable from a visit with dad, utterly terrified. >> i asked him what's wrong, tristan? he says, daddy says he's going to kill mommy and david. he is 5 years old. i don't think i 5-year-old makes that up. >> by then, brett was no longer on the police force and things weren't going so well for him. when sergeant watkins finished reviewing it all, the 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 works at the police department. they had not reached any agreements on these kids. i think that was his way of taking what he could from her. saying, those kids are not going to have you. >> was watkins right? we asked to hear the farrington side of the story from brad, or his family, we asked multiple times. they told us, they did not want to be interviewed. anyway, for sergeant watkins, the evidence was too compelling to ignore, especially what came right out of the autopsy, autos that the detective told to the prosecutor, told an unmistakable story. >> he said, a cop did this, this was someone who had been trained by police defensive tactics. >> what did you think when you heard that? >> i thought, we now have all the evidence we need to charge bradley farrington. >> five weeks after sergeant watkins took over the case and a year and 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 going to get off. coming up. at the 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 nervous. i just paced up and down the halls in and out. >> when "dateline" continues. e td felt embarrassing. i felt like disconnecting. i asked my doctor about treating my td, and learned about ingrezza. ♪ ingrezza ♪ ingrezza is clinically proven for reducing td. most people saw results in just two weeks. people taking ingrezza can stay on most mental health meds. only number-one prescribed ingrezza has simple dosing for td: always one pill, once daily. ingrezza can cause depression, suicidal thoughts, or actions in patients with huntington's disease. pay close attention to and call your doctor if you become depressed, have sudden changes in mood, behaviors, feelings, or have thoughts of suicide. don't take ingrezza if you're allergic to its ingredients. ingrezza may cause serious side effects, including angioedema, potential heart rhythm problems, and abnormal movements. report fevers, stiff muscles, or problems thinking as these may be life threatening. sleepiness is the most common side effect. take control by asking your doctor about ingrezza. ♪ ingrezza ♪ i'm adding downy unstopables to my wash. now i'll be smelling fresh all day long. [sniff] still fresh. ♪♪ get 6x longer-lasting freshness, plus odor protection. try for under $5! some people just know that the best rate for you is a rate based on you, with allstate. because there are people out there who aren't you. a lot of them. and you don't drive like... whoa. i don't want my child being raised by a robot! other drivers are not you. yes, thank you so much to all 50 of my subscribers. nope, definitely not you. save with drivewise and get a rate based on you. you're in good hands with allstate. norman, bad news... i never graduated from med school. what? but the good news is... xfinity mobile just got even better! now, you can automatically connect to wifi speeds up to a gig on the go. plus, buy one unlimited line and get one free for a year. i gotta get this deal... that's like $20 a month per unlimited line... i don't want to miss that. that's amazing doc. mobile savings are calling. visit xfinitymobile.com to learn more. doc? welcome back. when sergeant jess watkins took over the cassy b welcome back. when sergeant jess watkins took over the cassy farrington investigation, he came to know what her parents had been arguing from day one, cassy's ex-husband, brad, was the only person who would want her dead. now, brad was heading to court, charged with cassy's murder. but with no physical evidence tying him to the crime scene, could prosecutors prove it? here is keith morrison with the conclusion of "suspicion in silver city." it was the day that the brooks family feared they'd never see, brad farrington on trial for murdering cassy. >> i never thought we would get this far. >> too far? 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. >> no, and there was absolutely no evidence from the crime scene to help their case. the prosecution did not even call the now retired detective jose sanchez as a witness. >> we were rather brief on the scene. >> that was a weakness, actually. >> i don't know if i would call it a weakness, but it was not a strength. >> you should be in the diplomatic court. >> [ laughter ] well, there just wasn't anything there that was terribly useful. so we showed the jury the scene. this is where it happened. >> 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. >> so, one by one, cassy's friends repeated stories cassy told them about her fear of brad. >> there would be times where she felt like he was following her. >> and then cassy told the jury what she saw when brad was with cassy. >> and he had her in a choke hold on the bed. >> when you say a chokehold, can you describe for us how he was holding her? >> his arm was like this around her neck. >> to frighten, control? darlene was not sure. but shortly before she died, said her mom, cassy confessed , there was another reason too. >> he liked to choke her during sex. >> how did that relate to murder? remember, the medical examiner was vague about the cause of death, but not this guy dr. michael hunter, then chief medical examiner in san francisco. >> we are seeing bleeding within some of the muscles. >> he made it crystal clear to the jury that cassy's killer strangled her. >> once you see injuries to the neck hemorrhages, evidence of assault, that you can form an opinion, and i have formed an opinion, that this represents strangulation. >> but why should the jury describe brad did that? >> this is ed reynolds, retired silver city police chief, and also wants brad's police academy instructor, the man who taught him the chokehold. so eerily similar to what darlene demonstrated. segment his arm was up on her neck, like this. >> all of which was interesting, said defense attorney nathan gonzalez, but did not prove 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. >> 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. >> mr. farrington a suspect in your investigation? >> no, not my suspect, no. >> that was shocking because sanchez had told cassy's parents that he was a suspect. >> he believes there was an altercation in a fight and he took her and killed her and put her near the tub. he told us that a day after her murder.>> now in court, sanchez told a different way altogether, which if the jury believed it, could undermine the prosecution's entire case. >> i was focused already on mr. lee. >> mr. billy lee. >> why did you choose to focus on mr. lee? >> there were just too many discrepancies. >> remember, billy was cleared, had a solid alibi. now, the defense was using sanchez to raise doubt about who the real killer was here at >> there is a lot of smoke here, but no fire. >> muddles it up. >> and that, i believe, was the defense strategy, that if you have enough of that, that the jury won't see through it. >> the jury retired to consider. >> i was so nervous, i just paced up and down the halls, in and out. >> four hours later, they were called back into court. >> has the jury reached a verdict? can the deflated-- defendant please rise? we find the defendant, bradley farrington, guilty of first- degree murder. >> 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. i said, how could i, that was my little girl. >> brad farrington was sentenced to life, no parole for at least 30 years. cassy has been a memory now. so, her parents remember and walk through their pain by remembering the good in her life. the kids live with brad's family now. and when we last spoke to chuck and darlene, there one hope was to see their grandchildren again.>> they don't allow us to see or talk to them. >> what would you want to say to them if you could? >> that we love them. that their mom loved them unconditionally. that is all for this edition of "dateline." i'm andrea canning, thanks for watching. watching. good morning and welcome to this saturday edition of