Produced by Chuck Stevenson, Lucy Scott and Asena Basak
It's just about a 45-minute drive from the refineries of the Texas coast to the high rises of downtown Houston. And in 2000, 20-year-old Michelle Warner moved to the big city. She was a new mom looking to make a fresh start.
"Michelle did have the small-town girl in her, but Michelle always desired to go to the big city," Michelle's mom, Donna Malone, said. "She loved to talk to people... she never met a stranger."
"We were really, really close when we were young kids, I mean really close," her brother, David Chaffin added. "From the time we were born we did pretty much everything together ... from the time I was born I was her child, not theirs."
"She just grew into this beautiful swan ... she had the long pretty hair and a beautiful smile," Malone continued. "...she started going to college ... and started studying criminal justice."
But things didn't exactly work out. Michelle may have been a saint, but she was also a sinner.
She married right after high school and, in 2001, and had a daughter, Hayley.
When that marriage went south in 2003, little Hayley went to live with the ex-husband and Michelle was on her own.
"Michelle was a great mom," Malone explained, "but she ran into some tough times in her life."
She fell in with a bad crowd and she even disappeared a couple of times. And she was arrested for possession of cocaine.
But that was eight years ago. Her family says Michelle's dark days were behind her.
"She was finally turning around ... She was no longer on any kind of drugs," Malone said. "She was going to work every day."
In 2008, she also began a relationship with a man she met at work -- a man named Mark Castellano.
"My impression of Mark from the very beginning was, 'what an odd duck, what a strange little man,'" said Malone.
Mark Castellano and Michelle Warner had met on the job. She was a secretary at a medical firm; he was the IT guy -- the person who fixed computers.
"I absolutely do not know what Michelle saw in Mark," said Malone.
"He's always been a little off," said Chaffin.
In 2009, Michelle and Mark had a son, Cayden.
"Michelle was very excited when Cayden was born," Malone said. "I did have some reservations about Cayden's dad. ...Not so sure about Mark at all, no."
Malone says Castellano wasn't much of a dad.
"Cayden was about 2 months old and Mark just went away. Just, ' Ugh, I can't handle this; it's too stressful for me.' Everything was always about me - me, me, me, me, me."
In those early days, life was tough for Michelle as a single mom bouncing from job to job.
"No child support, he did not pay any child support. Michelle was doing it on her own -- struggling to do it on her own. It was very difficult for her," said Malone.
Then, in the summer of 2012, Michelle got a break -- a new job at a law firm in Houston. All she needed was a place for her and Cayden, now 3 years old, to stay. She reached out to the one person she knew there: Mark Castellano.
He agreed to let them stay at his Houston apartment, but Michelle set down some rules.
"When Michelle moved back in with Mark ... the agreement between them was that they would live together, raise the child together, but not as a romantically involved couple," said Malone.
But just three months after moving in with Castellano -- on Saturday, Sept 22, 2012 --Michelle was gone.
When Chaffin couldn't get a hold of his sister, he called Castellano and confronted him.
"Do you have any idea where she may be? I've exhausted every lead that I have about Michelle and I can't find a f-----g thing, anybody who knows anything about where she might be. And you're the last person I know of that's seen her," Chaffin asked Castellano.
"Yeah, yeah, I am, I am. But like I said, I don't know where the hell she went," Castellano replied.
Castellano told Chaffin that he and Michelle had had a fight. She'd walked out and left her car and her toddler behind.
Chaffin was surprised to learn that on the night his sister disappeared, Castellano took Michelle's car and drove Cayden more than 500 miles -- over eight hours -- to his parent's house in West Texas.
"Mark's story did not make any sense," said Malone.
Almost immediately, Michelle's family filed a missing persons report. They heard nothing. Five days later, veteran Houston homicide Detective Fil Waters and Sergeant Brian Harris got the case.
"When you first came here, you went in and what'd you do?" "48 Hours" correspondent Tracy Smith asked the investigators of the apartment where Castellano and Michelle lived together.
"Went to the apartment, the family was there," Det. Waters said. "Actually, it was interesting that Mark's story was what happened, you know, I mean in terms of the story that he was telling everyone."
Castellano had told Chaffin in that phone call that he and Michelle had been arguing over Cayden when she walked out.
"All of the events leading up to it, the fight, all the stuff that happened here," Smith noted.
"Accurate, at least what he is telling us" Waters said. "The only people in the scenario who were casting any kind of suspicion on Mark are Michelle's family, that's where all that's coming from. And they're not saying things like, 'You know what? Michelle told me yesterday that if anything ever happened to me it's Mark.'"
"We were getting, 'We don't like Mark ... Marks a bad guy,'" Waters continued. "It's more personality dislikes about Mark."
But back at the apartment, cops did find something strange.
"We knew that Mark was an IT guy. He's a techie nerd," Waters said. "So then, what becomes noticeable in the apartment ... there are computers ... but all the hard drives are gone."
The homicide detectives wanted to talk with Castellano, so they called him at his parent's house in West Texas. It turns out Castellano had an unusual question for them.
"He said, 'Can I ask you a question, though? I need some advice.' And I said, 'Sure.' And he said, 'Do you think I ought to let Dr Phil interview me?'" said Waters.
"What'd you say?" Smith asked.
"Well, I was a little stunned - I said, 'Dr. Phil?'" Waters said of the host of the top-rated daytime talk show. "And I said, 'Absolutely, let Dr. Phil interview you.'"
As the week passed, the search for Michelle Warner expanded quickly from Houston, to west Texas and all the way to Los Angeles and the "Dr. Phil" show.
"Dr. Phil": Today we will take you inside a national news story as it unfolded in front of our cameras in real time.
It was Dr. Phil McGraw -- not the police - who would first interrogate Castellano about Michelle's mysterious disappearance:
Dr. Phil: Let's talk about the night she disappeared. You had a fight? Was this a physical fight? Or an argument? Or both?
Mark Castellano: Basically, I come home. Umm, she's in her room. First thing she does is start yelling at me. Cayden has made a big mess ... and we start fighting ... she walks up to me and gives me this kind of sucker punch while I'm on the floor. I mean she hits me all the time and I don't retaliate. She hit me and said, "and clean it up right expletive, expletive," and she goes in and slams her door.
"What was your first impression of him?" Smith asked.
"That he was a game player, my first impression of him was that he thought he was the smartest guy in the room and he wanted everybody to know it," McGraw replied.
Dr. Phil: So you say she goes in, slams the door ... but you go back in to resume the argument, frankly.
Mark Castellano: Right, yes.
Dr. Phil: And...
Mark Castellano: She's gone
Dr. Phil: She's gone.
"I would take her pictures out and say out loud, 'Michelle where are you? You know just call me, text me please,'" said Malone.
From the very beginning, Dr. Phil McGraw felt there was something suspicious about Mark Castellano.
"Why do you think Mark Castellano wanted to come on your show?" Tracy Smith asked McGraw, whose show is distributed by CBS Television Distribution.
"I think this guy is a narcissist. I mean I really do," he replied.
Mark Castellano to Dr. Phil: She basically owns me in a lot of way and I admit that. I caved to Michelle nine-tenths of the time.
Castellano was on the defensive.
"He said to you, 'She could have just disappeared again,'" Smith commented to McGraw. "That was a possibility."
"Right," McGraw replied. "He says it was a possibility ... she could have gone in the bedroom, locked the door, gone out the door and left. But, her car's still there."
"And her son is still there," Smith noted.
"Her son is still there, her car is still there, but she's gone off the grid," said McGraw.
Meantime, in Houston -- 500 miles to the east -- the cops were searching the grid trying to find Michelle.
"We do something called a psychological autopsy. We start breaking down a person's life, and so that's what we were having to do with Michelle," Sgt. Harris explained.
Back in West Texas, McGraw continued his interview with Castellano. He had a hunch that those missing hard drives might be connected to Michelle's disappearance, so he grilled Mark:
Dr. Phil: You said you would show 'em to me. Do you have 'em here? Can we look at 'em?
Mark Castellano[gets up from his seat]: Yeah I'll bring 'em to you, one second. Oh, no I don't have 'em -- he's still copying 'em.
Dr. Phil: OK. You can come back.
Mark Castellano: Sorry, I thought he brought them back but he didn't.
Dr. Phil: You said you were gonna show those to us and you got up and walked to the door -- and then said, "Oh, that's right, they're not here." But not 15 minutes before we got here, you told my producer they weren't here. You already knew they weren't here when you got up to get 'em.
Mark Castellano: My mind is scatterbrained right now. I mean I forgot.
"I forgot?" said Smith.
"Bells are going off right now. I'm talking to him and watching ... the theatre of what's going on," McGraw said. "He's playing games here. To him, it's a manipulation ... and I'm wondering why he's not putting all of his effort, all of his emphasis, on finding Michelle?"
"My dad used to say for every rat you see there's 50 you don't. When he tells you that lie, there's 50 more," McGraw continued.
McGraw relentlessly peeled back Castellano's story.
"He also admits throwing her cat down the hallway, throwing her cat into a wall. And that is very troubling to me," said McGraw.
Each revelation led him closer to the conclusion that Castellano killed Michelle:
Dr. Phil: Was there violence at this point?
Mark Castellano: There was violence ... She and I would wrestle ... push each other around. There was one time I choked her.
"He admits to being violent with her," said Smith.
"He admits to being violent with her to the point of choking her. Now think about this: if he, in fact, is culpable in her disappearance, why in the world would he admit that?" said McGraw.
"So let's look at the moment when you asked him the big question," Smith said as she and McGraw watched more of the TV interview:
Dr. Phil: It's really odd for a mother to just not check on, find out anything about a child. If you think something has happened to her, why aren't you looking for her?
Mark Castellano: I mean, as far as everybody has exhausted the leads that I have. I don't know where else to go. The police are looking for her. They're professionals.
Dr. Phil: Did you do anything to her that would be considered foul play or criminal?
Mark Castellano: No, no.
Dr. Phil: Did you kill her?
Mark Castellano: No, sir.
"So as you left, where did you stand with Mark Castellano? What did you think?" Smith asked McGraw.
"It is clear in my mind that I'm not believing a word he is saying," he replied. "When I walked out the door ... I said, 'He killed her, no doubt about it.'"
"You said it then?" Smith asked.
"He killed her," said McGraw.
But Castellano hadn't confessed to anything. After McGraw returned to Los Angeles to get his show ready for broadcast, detectives brought Castellano in and turned up the heat.
It all happened in an interview room at the Houston homicide division. There was no tough guy posturing, no rolled up shirtsleeves or guns on the hip, and no raised voices -- it was pure psychology.
"I was like, Fil, when you go in there, it's like walking into a minefield, because one, you don't wanna upset him and make him angry where all of sudden he says the L word - lawyer, or he says, I wanna leave," said Sgt. Harris.
Detective Fil Waters takes the lead:
Det. Waters: OK, so the first thing, you're not under arrest.
Mark Castellano: Right.
Det. Waters: Again, I told ya I certainly appreciate you coming here and talking to us, spending a lot of time here.
Mark Castellano: Well I want Michelle to be found.
"I want Michelle to be found." That's what Castellano just said. That's his story and he's sticking to it:
Det. Waters: Have you tried to call her?
Mark Castellano: At this point? No, I don't want to call her.
"This was it. This was it," Waters told Smith. "We had no evidence, we had nothing."
So, Detective Waters started looking for motive. If Castellano was a killer, did something push him over the edge?
Det. Waters: Pressure's building?
Mark Castellano: The pressure's building on me, yes. When she gets mad, she's violent. She'll hit you, she thinks she has the right to ... you know, the man has to take up crap. She's a pretty girl and she gets everything she wants. She has that princess attitude.
That "princess attitude" phrase was a flag for detectives -- an insight into how Castellano viewed the relationship:
Det. Waters: We kind of get a flavor of your relationship. And this is my impression -- is that when it's good, it's like intensely good. But when it is bad, it is intensely bad.
Mark Castellano: Right.
Detective Waters' approach? No tough questions - yet. He is trying to get Castellano to trust him:
Det. Waters: Let's get to last Saturday, the 22nd.
Mark Castellano: OK, she walks out and slams the door to her room ... and about, 10, 15 minutes later I open the door to say, "Well, you know what" and she's gone.
"Once that narrative was complete, and he felt like he had told his story, it was at that point that - I'm now gonna confront you," Waters told Smith.
"This is a dance," Waters continued. "And I'm letting Mark play the music. And then at one point, another song comes on and it's mine, and now the dance changes."
Waters tells Castellano: "I need you to explain to me what happened. ... We both know, we both know, Michelle did not walk out of that apartment."
Detective Fil Waters sat for hours talking to Mark Castellano, gaining his trust:
Mark Castellano: I don't love her. I'm not in love her. I don't want anything to happen to her. I wish Michelle would pop up right now. When she gets mad she's violent I don't care what anybody she says, she is. I said something about you take too many pills, you can't watch Cayden or something.
She's like, "I can't tolerate Cayden." She's like, "I need help with him." She's like, "he's driving me nuts."
Waters finally discovered a way to bring out the truth about what happened that night: he brought up Cayden.
Det. Waters: So your concern for Cayden is mainly centered on when Michelle is the primary - caregiver.
Mark Castellano: Right.
"Cayden was the most important part of his life," Waters told Smith, "so I knew that I was going to have to frame whatever he did in that apartment in that context."
That context -- getting Castellano to admit his actions that night were to protect Cayden:
Det. Waters: It wasn't about hurting Michelle. It was about the love and the strength of that love that you have for Cayden and protecting him from anybody that would threaten to hurt him. And that's what you're gonna have to explain now.
The strategy worked.
Det. Waters: So I want you to be honest with me and tell me what happened.
"When he took off his glasses, I went -- here it comes," Waters told Smith. "I just knew it."
Mark Castellano: She's getting dressed. And she's finishing up and she's still yelling and Cayden's hiding. I grabbed her and I broke her neck.
"Boom. There he comes with it," Waters told Smith.
Mark Castellano [in tears]: I'm sorry, I'm sorry. F-----g give me the death penalty, that's fine. I deserve it.
Det. Waters: Mark, Mark look, I'm proud of you.
Mark Castellano: My life's over with anyway.
Det. Waters: Your life's not over with, Mark.
Sergeant Harris came into the room and Castellano physically demonstrated how he killed Michelle:
Mark Castellano: Then I grab her, and then at about that I'm facing the bed and then I fall on top of her and crush her windpipe.
Castellano demonstrated several times how he strangled Michelle Warner, even pushing Sgt. Harris onto the tabletop to show how he spent one-and-a-half to two minutes choking her.
Castellano claimed Michelle's erratic and abusive behavior pushed him over the edge.
Mark Castellano: She'll hit you; she thinks she has the right to.
"He painted this picture of Michelle as an abusive woman," Smith said. "When you talk to other people did they say that she was volatile? She had a temper? She was abusive?"
"Everyone we talked to, not just family members, described her as a loving mother," said Harris.
"Was there any evidence that Michelle was abusive to Mark?"
"Not anything that was documented ... other than Marks story," Waters replied.
After his confession, Castellano is left alone with his phone. Instead of calling a lawyer, he called his parents: "Hey Mom. Well, I confessed. I did it."
He called his brother: "I'm sorry for all he façade I put up for a week, but I can't take the guilt anymore."
He called a friend: "And I wanted you to know that she's dead."
He even talked with Dr. Phil's producer: "It was a moment of rage, I just - I couldn't take it anymore."
Mark Castellano to Det. Waters: I pretty much confessed to everybody I could think of.
Castellano had also told Detective Waters what happened moments after he killed Michelle -- as he stood over her body, lying on the bed.
"He said that Cayden walked in and said, 'What's wrong with Mommy?'" Waters said. "And he turned around and his response was, 'Mommy's taking a nap.'"
Castellano put Cayden in a bath, and then dragged Michelle's body into the closet.
Soon after, he loaded Cayden into Michelle's car and drove through the night, over 500 miles, to West Texas.
He left Cayden with his parents, turned around and drove all the way back to Houston -- back to the apartment where he had left Michelle.
"How did he get her out of the building?" Smith asked Waters.
"He packaged her up in a large container, plastic container, and duct taped her hands and feet, put a bag over her head," he replied. "He explained he put a bag over her head 'cause he was tired of looking at her."
With the container loaded in the backseat of Michelle's car, Castellano once again made that long drive back to West Texas. Outside of Midland, he buried Michelle in a shallow grave.
It turned out Michelle's body was somewhere out in the endless West Texas oil fields. Castellano had drawn a map and given police a rough idea of where the grave was. But it wasn't a good enough description. The key to finding Michelle's body was as close as an iPhone.
Harris and Walters stayed in Houston with Castellano, while local police and FBI agents tried to locate Michelle's body with the map. But it only got them in the general vicinity.
"So they called us in the interview room and we decided to try the FaceTime," said Harris.
FaceTime is the Apple iPhone's video phone app. You can see and hear whatever the person on the other end of the line wants to show you.
"Mark was actually speaking to the detectives and they were holding their phone out," Harris explained via FaceTime. "They tried to follow it like a treasure map."
"Just walking around aiming it," said Smith.
"Correct. And so they panned the area and then he told them to stop and he directed 'em towards - it was like more of a big scrub brush," Harris said. "When they got closer, that's when the FBI agent -- we could hear her say, 'I found her, I found her.'"
With the discovery of Michelle's body, Castellano was finally arrested and charged with murder eight days after she went missing.
Dr. Phil McGraw's show went on TV a few days later.
Until Castellano's confession, Cayden had been staying with his relatives. But now, authorities moved him in with Michelle's family.
When "48 Hours" caught up with Castellano behind bars, there were a few other things he wanted us to know, including a brand new version of what happened that night -- a 180-degree turnaround.
CASTELLANO'S OTHER STORY
From the start, Mark Castellano had told everyone lies. So "48 Hours"' Correspondent Tracy Smith wanted to set the ground rules before their interview.
"So here's the thing Mark. You lied to the cops, you lied to Dr. Phil, you lied to your parents ... why should we believe you now?" Smith asked.
"What's the -- there's no point to lie about anything," Castellano replied. "I don't like lying. I don't like lying at all. It's not me. I'd rather just go ahead and tell the truth and get it over with.
"Are you telling me the truth now?" Smith asked.
"Yes. Of course I'm telling you the truth," he said.
The first thing Castellano wanted to tell "48 Hours" was that he was not a murderer.
"We got into a fight it just - it just happened all wrong," he told Smith. "It wasn't, you know, not my finest hour."
"Not your finest hour?"
"No," said Castellano.
"Why do you say that?" Smith asked.
"Well, I mean the whole thing wasn't my finest hour," Castellano replied.
He says yes, it was true -- the couple had a fight that night, but he was the victim.
Asked if it got violent, Castellano said, "Oh yeah, they always get violent. She beats the hell out of me. ...I've been beaten by this woman for a long time."
But this time Castellano says he'd had enough. Remember - there's never been an official report of abuse in this case.
"So, did you just snap?" Smith asked.
"...to, to retaliate back from her swinging at me? Yeah," he replied. "I snapped or hit her back ... this time I was tired of being hit ... and yeah, then I was gonna defend myself this time around."
"So you threw stuff back and forth and then you grabbed her," said Smith.
"I didn't grab her yet. She threw another punch at me," Castellano said. "That's when I grabbed her and lunged forward."
This is where Castellano's story changes from his confession to police:
Mark Castellano to Det. Waters: "I grabbed her and I broke her neck.
"So I want to go back to this confession. What actually happened that night?" Smith asked.
"That's what we're not going to talk about," Castellano's lawyer interrupted, telling him not to reveal all of what happened that night.
Still, he did tell "48 Hours" a few details. Castellano now says it was all an accident. In the struggle, he says, Michelle died when he ended up falling on top of her neck.
"Michelle's death was my fault because ... I'm the one that fell on her," said Castellano.
"That fell on her," Smith repeated.
"Yes, I did fall on her. I mean, she just, like that, I mean she was just lifeless," Castellano said, snapping his head back. "And all of a sudden you know, her body let go ... and it was an accident."
Michelle's mother, Donna Malone, can barely contain her disgust.
"First of all, I will never believe it was just an accident," she said. "You just don't on accident murder someone and feel nothing."
"When you drive a car and you hit somebody, did you want to hit them, no. You're like, 'It was an accident. ...' You might be at someone's house and they just had brand new carpet put in and you're eating velvet cake and you dropped in on the floor. Did you want to do it, no. Do you feel bad about it, yes. But still, accidents are still accidents, they are not planned. That's why they're called accidents," Castellano went on, shedding a tear.
That tear was the only time during the interview that Castellano showed any emotion.
"He's a liar," Malone said. "Comparing it to spilling cake on someone's floor? To murder someone, that's a violent act."
"Did you choke her?" Smith asked Castellano.
"No, I didn't choke her," he replied.
"But you said you were angry."
"Oh, I was very angry."
"You said you snapped," Smith continued.
"Yeah, and to go ahead and actually raise my hands against her," Castellano said. "I had a gun. I've always had a 9mm. If I really wanted to kill Michelle, I would have shot her. ...I would have taken my gun and shot her."
"That he could just have shot her if he wanted to kill her, that's just nonsense talk. It's nonsense," said Malone.
"What did you do with Michelle's body," Smith asked.
"Ummm, it stayed, it stayed, ummm, it stayed in the closet. You know ... I looked at her and it was just like 'Oh, my god.' So that's when I put the bag over her head and I put her in the closet."
"Why the bag over her head?" Smith asked.
"Because, just her face -- the way it was frozen," Castellano told Smith. "I knew I messed up."
"Did it occur to you as you were handling her body that this was the woman that you loved? That this was the mother of your child?" Smith pressed.
"I did I did. And I also know I couldn't bring her back," he said.
Three days later, Castellano would dump Michelle's lifeless body in that shallow grave.
Asked how he feels about misleading people for so long, Castellano told Smith, "Well, it was a tough call. ...It was a very tough call. ...I didn't plan on getting away with this. If I had planned on getting away with this, I would have gotten away with it."
"I feel very angry about the fact that Mark lied to all of us. He could have just told the truth from the beginning. It was obvious that everyone was onto him -- family, law enforcement. Why not just tell the truth, get it over with," said Malone.
"She did attack me first," Castellano told Smith.
The more Mark Castellano talked, the more it seemed he was angry with women.
"I mean that's just a fact. Women are now -- y'all are replacing men in a lot of aspects. Ya'll are becoming big time aggressors," he said. "Women are now the new aggressors."
"She was beautiful, and you're a beautiful woman yourself. Life's a little easier for women like you, because people can't put bad things with pretty people," Castellano continued.
"It sounds like you resent that a little bit, Mark," Smith commented.
"Well, when you sit there and have been told that when you're are not a pretty person, that, ya know, life's gonna suck for you..." he replied.
Mark Castellano's bizarre answers during "48 Hours"' jailhouse interview raised more questions about what makes him tick. So we wanted to talk more about it with Dr. Phil McGraw.
Mark Castellano to Tracy Smith: I gotta say I really screwed myself over the way I confessed everything. And because, first of all, I didn't really describe everything accurately, and second of all, I didn't really think every word was going to be used completely out of context, which it was in a lot of ways.
"He's criticizing the process. Things were taken out of context. Here's the context: did you kill her? Or did you not? I think this guy has such an inferiority complex and that's one of the things about narcissism. There's a false sense of superiority, but it's a false sense of superiority," McGraw said as he and Smith watched the interview.
"The truth is, they really feel inferior," said Smith.
"They really feel very inferior, very put upon. And he felt very much that he had reached above his level with Michelle," said McGraw.
"That she was out of his league, so to speak," Smith noted.
"Out of his league. She was way over his head. In this instance, she did not reject him. He had the ultimate rejection of her," said McGraw.
"What do you think his motive was?" Smith asked.
"I think this guy is very hedonistic," McGraw replied. "I think this relationship was on the down slope. I think it was falling apart. And I think he felt her slipping away. ...I think it was one of those situations where, 'If I can't have you, nobody will.'"
At his trial, Castellano's attorneys will present his new version of what he says is the truth. Will the jury buy it?
FACING A JURY
"It was very hard to wait on the trial. We wanted some form of justice for Michelle," Donna Malone, said. "We felt that we were building up to this pinnacle ... that would bring us some sort of peace."
May 27, 2014. Mark Castellano is on trial for the murder of Michelle Warner, the mother of their son, Cayden.
"This is a case about obsession, rage, and this defendant's calculated attempts to get away with murder," Assistant District Attorney Jamie Reyna told the court in her opening. "He became so upset with Michelle, that he grabbed her by the neck ... that he started to choke her, he started to squeeze her neck. You'll hear him tell those officers he choked her for one-and-a-half to two minutes."
At the center of the prosecution's case - Castellano's own words -- that videotaped confession to Detective Waters:
Det. Waters[interrogation]: We both know Michelle didn't walk out of that apartment. So I want you to be honest with me, and tell me what happened...
Mark Castellano: I grabbed her and I broke her neck.
The state medical examiner testifies Michelle was strangled. Her hyoid bone, just beneath her jaw, was broken.
Mark Castellano does not take the stand. Instead, his lawyer presents that very different story: Michelle's death was an accident.
"...she comes at him, he grabs her, he's controlling her and he falls down with his weight on hers and hears a pop. When he reached out to defend himself to protect himself. He didn't anticipate that she would fall down and break her neck," defense attorney Eric Davis told jurors.
An expert for the defense, a forensic engineer, testifies Castellano's accident story was a possibility.
"I didn't find any real evidence that the throat was disturbed," John Charles Laughlin testified. "There's no physical evidence that shows any type of squeezing or sideways forces. All of the physical evidence shows is forces applied from the front."
So what's the detectives' reaction to Castellano's defense?
"Is that possible that he fell on her and that's how her neck snapped?" Smith asked Sgt. Brian Harris.
"No," he replied.
"The problem is that you cannot accidentally strangle someone for a minute-and-a half to two minutes," said Det. Fil Waters.
"Show me what you think he did, what he told you he did to Michelle. What did he do?" Smith asked Harris.
"He's so mad he follows her in the bedroom and he goes and whatever takes place, he reaches out and he's just grabbing her, for a minute-and-a-half or two. He's grabbing her, grabbing her, and she has nowhere to go," said Harris.
If Castellano thought the jury might take pity on him, prosecutors would present more evidence that shows the actions of a cold, callous killer.
Weeks after Castellano's confession, detectives discovered a chilling piece of surveillance video taken by a camera on a building located across from his apartment.
The video showed a shadowy view of the back stairs of Castellano's apartment.
"So he drags her body in a bin down the stairs," Smith said of the video, which shows a figure dragging something.
"You see him stop. He has worn himself out," Waters explained. "He even says when he's on the phone with people he's confessing to, 'You know, Michelle had gained a lot of weight.' So it was really an exercise to bring her down the steps and put her in the car."
As for those hard drives that seemed to be so important in the early days of the investigation? It turns out they weren't relevant to the case.
After more than a week of testimony, 19 witnesses and six hours of deliberations, there's a verdict, ending an anxious wait for Michelle's family.
Mark Castellano is found guilty in the strangling death of Michelle Warner.
"I was very pleased with the fact that he was declared guilty," Malone said. "I said, 'OK, good. They did this quickly... so I believe that this is in the hands of a good, solid jury and they'll do the right thing.'"
The next day, Michelle's loved ones are back in court for Castellano's sentencing. Ironically, it's also Michelle's birthday. She would have turned 33.
Mark Castellano's attorney begs for mercy and argues his client's much-talked-about confession was a show of remorse.
"The crime was solved because of a man's conscious. ...In fact, if Mr. Castellano had kept his mouth shut, we wouldn't be here ... But he did what most criminals don't do. He told on himself," Davis told the court. "No matter what you do, he is going to the penitentiary. The question is how long?"
Michelle's family wants to see Castellano receive the harshest penalty: life in prison.
"I do not think that he has any sense of remorse. None," Malone said. I hear nothing but excuses that it was Michelle's fault that he did what he did and we all have free choice and he chose to kill her."
The jurors spend four hours debating his fate. Finally, a decision: Castellano is sentenced to 27 years.
While Castellano mouths "thank you" to the jury, the sentence feels like a slap in the face for Michelle's family.
"One word went through my mind when I heard 27 years -- seriously?" Malone said following the decision.
After several months, it is still impossible for the family to understand the jury's decision.
"I don't know what happened in the room while the deliberation was going on, because I've not -- had not one juror come forward and speak to me," Malone said. "I do not feel that I got closure for my daughter's death, and neither does any of the rest of her family. None of us do."
Now it is up to Michelle's family to explain to two kids -- a daughter living with her ex-husband and little Cayden -- why their mother is gone.
"It's like taking your entire world and flipping it over," David Chaffin said of his sister's murder. "You don't expect anything like that to ever hit that close to home for you ... and it's turmoil."
"I miss the laughter that I shared with her. ...And I just miss the conversation. I can't have that any more," Malone said. "And that's very sad. It's very lonely. ... It makes me feel lonely. So it's an empty hole that will always be there, for the rest of my life. And that's a hard thing to swallow."
Mark Castellano will be eligible for parole in 13-and-a-half years. He will be 53 years old.