MURDEROUS MINDS: The Killer Step-Brother Pt. 2

Nathan Matthews murdered his 16-year-old stepsister Becky Watts—then helped her family search for her. In Part 2, we break down the failed cover-up, the forensic clues that exposed him, and how the truth about one of Britain’s most disturbing family murders finally came to light. Killer Minds is a Crime House Original Podcast, powered by PAVE Studios. Listen wherever you get your podcasts. For ad-free listening and early access to episodes, subscribe to Crime House+ on Apple Podcasts. Don’t miss out on all things Killer Minds! Instagram: @killerminds https://www.instagram.com/killerminds/ | @Crimehouse https://www.instagram.com/crimehouse/ TikTok: @Crimehouse https://www.tiktok.com/@crimehouse Facebook: @crimehousestudios https://www.facebook.com/crimehousestudios X: @crimehousemedia https://x.com/crimehousemedia YouTube: @crimehousestudios https://www.youtube.com/@crimehousestudios

Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.

• 0:01Vanessa Richardson?

  Hi, everyone. Before today's episode, there's another show I want to tell you about. It's called What the Fact with Connor Tomlinson from Netflix's Love on the Spectrum and Carter Roy. Every week, they take three unbelievable true facts from history and tell you the full story behind them. Plus, Connor's infectious energy that'll make you realize history is the most fascinating thing on earth. Follow What the Fact wherever you listen, or subscribe on YouTube at What the Fact Pod.

• 0:36Speaker 01

  This is Crime House.

• 0:41Vanessa Richardson?

  Sibling rivalries can be intense, especially when one child feels like their parents give their brother or sister preferential treatment. The resentment can get even more intense when it comes to blended families. The competition gets fierce: one-upmanship, small acts of sabotage, maybe the occasional fistfight. But as we get older, those feelings fade away. You might never be best friends, but it's usually easy enough to coexist. That wasn't the case with Nathan Matthews. Even though he was almost 30 years old with a family of his own, Nathan couldn't get over the hatred he felt for his teenage stepsister,

• 1:24Vanessa Richardson?

  Becky Watts. And instead of trying to move past those feelings, he let them consume him. Until there was nothing left.

• 1:48Vanessa Richardson?

  The human mind is powerful. It shapes how we think, feel, love, and hate. But sometimes it drives people to commit the unthinkable. This is Killer Minds, a Crime House original. I'm Vanessa Richardson.

• 2:04Tristin Engels?

  And I'm Dr. Tristin Engels. Every Monday and Thursday, we uncover the darkest minds in history, analyzing what makes a killer.

• 2:12Vanessa Richardson?

  Crime House is made possible by you. Please rate, review, and follow Killer Minds. To enhance your listening experience with ad-free, early access to each two-part series and bonus content, subscribe to Crime House Plus on Apple Podcasts.

• 2:28Vanessa Richardson?

  Before we get started, be advised that this episode contains descriptions of murder, kidnapping, and child sex abuse material involving teenage girls. Listener discretion is advised. Today, we conclude our deep dive on Nathan Matthews, a former British Territorial Army veteran who struggled with complicated family dynamics from a young age. As an adult, his self-isolation and addiction to violent pornography distorted his reality to the point where he developed a terrifying hatred towards his teenage stepsister. It was a fixation that would ultimately end in tragedy.

• 3:08Tristin Engels?

  As Vanessa goes through the story, I'll be talking about things like a first-time killer's mental state as they cover up a crime, how a guilty person can act or react when being questioned, and how a shared obsession between couples can create a shared delusion.

• 3:24Vanessa Richardson?

  And as always, we'll be asking the question, what makes a killer? On February 19, 2015, 16-year-old Becky Watts was home alone in Bristol, a city in the United Kingdom. It was a Thursday, and Becky's dad, Darren Galsworthy, was at work. Meanwhile, her stepmother, Angie, was at a medical appointment. But Becky wouldn't be by herself for long. At some point that day, after 11:00 a.m., when Angie left for her appointment and well before 12:45 p.m., when she returned home, Becky's stepbrother, 28-year-old Nathan Matthews,

• 4:09Vanessa Richardson?

  and his girlfriend, 21-year-old Shauna Hor, arrived at the house. They stopped by a lot, so the fact that they were visiting wasn't unusual. However, the reason for their visit that day was anything but usual.

• 4:25Vanessa Richardson?

  For years, Nathan had resented Becky. First, for taking all his mother's attention, and then for being disrespectful to Angie, or at least, in Nathan's mind, she was. To get her to stop, he was planning on teaching Becky a terrifying lesson. When Nathan and Shauna arrived, he was wearing a mask and had a large bag containing handcuffs, a stun gun, and tape. For a long time now, he'd fantasized about kidnapping a teenage girl. He'd supposedly decided to indulge that desire by fake kidnapping Becky and scaring her straight in the process.

• 5:05Vanessa Richardson?

  Once Nathan and Shauna were inside, she went out to the garden for a cigarette while Nathan went upstairs to Becky's room. He stormed in to find his stepsister, then taped her mouth shut and told her, "As long as you do as you're told, you are going to be fine." Nathan took out the handcuffs and clamped them on Becky's wrists. Then he tried to shove her into the bag, but she fought back. The specific sequence of events isn't clear, but during the ensuing scuffle, Nathan punched Becky, causing her to bleed from her mouth. Then he grabbed her throat and utilized a technique he'd learned in military school to restrict blood flow to the head.

• 5:48Vanessa Richardson?

  When he did this, she stopped fighting back. And she also stopped breathing. Becky was dead.

• 5:59Tristin Engels?

  Let's talk about the psychology of someone who goes from fantasy to actualization like this. For individuals like Nathan, the fantasy offers something intoxicating, its power without consequence. But reality never plays out the way it does in the fantasy. Real people resist, or they fight back. They bleed, they cry, or they scream. And for someone whose self-worth hinges on control, that resistance can trigger panic, or rage, or even escalation. Sometimes, the individual realizes they're in over their head, and they retreat. But others, especially those with poor emotional regulation and a high sense of entitlement, double down. They move from controlled performance to chaotic violence. And that's what we likely saw here with Nathan.

• 6:43Vanessa Richardson?

  So siblicide is not something I've heard about often. How common is it? And what are some of the common psychological traits of someone who actually kills a sibling?

• 6:53Tristin Engels?

  Yeah, siblicide, the killing of one sibling by another, is rare, but not unheard of. And in terms of statistics, it's estimated to make up around 1 to 3% of all homicides in most countries. So while it's certainly not common, when it does happen, it tends to draw intense attention because it violates such a fundamental social norm, which is the idea that family, even siblings, are supposed to protect one another, not harm one another like that. So now, when it does occur, we often find a constellation of psychological risk factors in the offender. There isn't a single profile, but patterns do emerge. And as forensic psychologists, we look at patterns.

• 7:35Tristin Engels?

  So for example, chronic resentment is a pattern, jealousy, a history of parental neglect or inconsistent caregiving, exposure to violence early on, personality disorders, emotional dysregulation, and family dysfunction are all common patterns. And when we consider that, it's clear that many of these existed in Nathan that went unnoticed.

• 7:58Vanessa Richardson?

  Whether or not Nathan intended to kill Becky, once he realized she was dead, he stuffed her body in the bag. Then he brought it out, put it in the trunk of his car, and went back inside to watch TV with Shawna until his mother, Angie, returned.

• 8:16Tristin Engels?

  This is evidence of emotional compartmentalization or callousness.

• 8:20Vanessa Richardson?

  Angie came home just before 1:00 PM, and although she realized Becky wasn't there, she just assumed her stepdaughter was out with friends. At some point, Becky's boyfriend Luke stopped by to see her, but Shawna told him that she was out. The couple stayed there, watching TV and talking with Angie until around 7:00 PM, before calling it a night and heading back to their place. It's unclear if Shawna knew what was in the trunk of Nathan's car, but he certainly did, and he kept acting like everything was completely normal. When they got home, the couple ordered takeout Chinese food and talked about what to watch on TV. The next day, the couple returned to Darren and Angie's house with their two-year-old child.

• 9:05Vanessa Richardson?

  It's hard to tell if they went over unannounced, or if Angie had called them, but by that point, it was clear that Becky was missing. A group of her friends had come over. They hadn't heard from Becky since the day before, and they were worried about her. Until that point, Angie had assumed that Becky was out with them, but now, nobody had any idea where she was. Shortly after Nathan and Shauna arrived, Becky's dad, Darren, sped home from work. Once he got there, Darren and one of Becky's friends went upstairs to her room to look for any clues. They quickly realized her phone and laptop were missing, which was alarming. Becky never took her computer out of the house. Darren feared the worst.

• 9:50Vanessa Richardson?

  At this point, it was 4:00 PM. Nobody had heard from Becky in over 24 hours. He decided it was time to call 999, the UK's equivalent of 911. It was all pretty scary, but there was still hope she'd turn up. It wasn't uncommon for teenagers to go missing in the Bristol area, and they'd often make it home safe, either found by law enforcement or friends and family. Nathan knew that wasn't going to happen, but he put up a good front. He played the part of the concerned stepbrother to perfection. Before the police arrived, Nathan helped Darren post a picture of Becky on Facebook, along with a message that she was missing.

• 10:32Tristin Engels?

  So his post-defense behavior is actually common in individuals with narcissistic or antisocial traits. They don't panic in the way a typical person might. Instead, they pivot into damage control, inserting themselves into the search, the narrative, even the center of sympathy. And that's not because they care, it's because it allows them to manage how others see them. Nathan helping his stepfather post on Facebook about Becky's disappearance is a perfect example of this. It may have served several psychological purposes, like deflection, narrative control, and satisfaction, because he has sadistic He would feel a perverse sense of power in knowing that he holds the truth while everyone else is scrambling to find it.

• 11:17Tristin Engels?

  Nathan's callous post-offense behavior also suggests this had nothing to do with feelings of guilt or remorse, but it is possible he felt some level of anxiety about being caught. So he went into performance mode to mitigate any potential consequences.

• 11:32Vanessa Richardson?

  Well, for the time being, nobody suspected that Nathan and Shauna had anything to do with Becky's disappearance. And although the police asked them about their activities the day before, it seemed to be in a purely informational capacity. Nathan told them that when he and Shauna came over at some point before 12:45 PM, they'd heard music in Becky's room. Shauna added that she heard the front door slam shut while she was in the garden, although she never actually saw Becky leave the house. Over the next few days, the police launched their missing persons investigation, and people all over Bristol volunteered to join the search party.

• 12:13Vanessa Richardson?

  The turnout was so large, it seemed like everyone in the city had joined, except Nathan and Shauna. Nathan was busy, making sure the investigators never found Becky, and Shauna, whose role in the murder was unclear up until this point, was helping him. The day after Becky's murder, likely right after he spoke to the police, Nathan went to a home improvement store and bought a circular power saw, gloves, face masks, and goggles. Then, two days later, on February 22nd, he and Shauna bought trash bags, rubble sacks, rubber gloves, bleach, and three rolls of cling wrap.

• 12:55Vanessa Richardson?

  They went to multiple stores to get the rest of their supplies, more tape, sponges, and rubble sacks.

• 13:02Vanessa Richardson?

  Once they had everything they needed, Nathan used the power saw to dismember Becky's body in his bathtub. Shawna was home during this time, and she allegedly assisted Nathan in carefully packing the remains into bags, wrapped in cling wrap and tape. One of them even searched on their phone, "Do you want to hide a dead body?" Nathan, and possibly Shawna, then used the cleaning products they bought and scrubbed down their house, especially their bathtub. Meanwhile, the search for Becky was intensifying, and the public was hard at work, too. A social media campaign started around this time with the hashtag #FindBecky trending.

• 13:46Vanessa Richardson?

  Community search parties continued as well, with impressive turnouts. And while most of the family was constantly at Darren and Angie's house making posters and handing out leaflets, Nathan and Shawna were conspicuously absent.

• 14:02Tristin Engels?

  Okay, so while the rest of the family was in crisis mode, Nathan was trying to do two very contradictory things. He's maintaining the illusion of normalcy and attempting to contain the reality of what he'd done by working hard to cover it up. That kind of duality is incredibly difficult to sustain for most people. But Nathan has been living in that duality for most of his life now. Overall, his behavior isn't atypical. We see this sometimes in individuals with narcissistic or antisocial traits. They, like I said, lean into rationalization, compartmentalization, and arrogance. And that's what he appears to be doing here, because again, he's trying to maintain some resemblance of control.

• 14:43Vanessa Richardson?

  We've covered serial killers on this show who also dismembered their victims, like Jeffrey Dahmer, Joel Rifkin. Both of those men were like Nathan in some ways. They were lonely and disconnected from the world. Is it significant that they disposed of their victims in the same way? Is there anything we can learn about Nathan from that?

• 15:03Tristin Engels?

  Yes, it's significant, especially when we consider the underlying psychological motivations. Dismemberment is rarely spontaneous, and while it may serve practical purposes like concealment or hindering identification of the victim, it often reflects far more than that. Psychologically, it's frequently associated with individuals who exhibit marked emotional detachment, fantasy-driven control, and a need to dominate or dehumanize the victim, all of which are consistent with Nathan, as well as Joel Rifkin and Jeffrey Dahmer. And although Nathan is not a serial killer, he certainly shares traits with them, which means it's highly possible he would have got on to become one if he hadn't been caught.

• 15:45Vanessa Richardson?

  Well, for the time being, the police were still buying Nathan's act. And on February 24th, four days after Becky was reported missing, he gathered the neatly packaged bags that contained her remains and brought them to a friend's shed. This friend lived very close by, just a few hundred feet from Nathan's house. There, allegedly unbeknownst to the friend, Nathan hid all the evidence from his crime. But he didn't realize he left something behind on the day of the murder, and after multiple searches of Becky's house, the forensics team finally found it. Outside Becky's bedroom, on her doorframe, were three tiny smears of blood, along with

• 16:30Vanessa Richardson?

  a clear outline of a fingerprint.

• 16:40Vanessa Richardson?

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• 17:59Speaker 03

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• 18:04Speaker 04

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• 18:07Speaker 03

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• 18:13Speaker 05

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• 18:22Speaker 03

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• 18:30Speaker 06

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• 19:01Vanessa Richardson?

  Sometime during the week after Becky Watts disappeared in February 2015, forensic investigators found a bloody fingerprint on her bedroom door frame. This was a huge breakthrough for two reasons. One, it was a huge piece of forensic evidence that they could test against future suspects. And two, the blood indicated that Becky had been injured and forcibly removed from her home, which allowed detectives to broaden their investigation. Because now, they weren't just looking for a missing person, they were looking for a kidnapping victim. After this discovery, more law enforcement jurisdictions were brought in to assist the Bristol Police. More manpower meant more scrutiny,

• 19:46Vanessa Richardson?

  and the first order of business was to re-interview Becky's family. And this time, Nathan was much less cooperative. He kept making excuses about why he couldn't come in, which raised the investigators' suspicions. But when he did eventually sit down with them, he was surprisingly calm and relaxed, approachable even. Nathan even laughed and joked with the officer conducting the interview.

• 20:13Tristin Engels?

  Nathan's demeanor during the second interview was noteworthy because he was unexpectedly calm, even lighthearted. But now, it's important to clarify, behavior alone doesn't determine guilt or innocence. People respond to high-stress situations in a wide range of ways. Some innocent individuals shut down or seem evasive. Some guilty individuals appear composed. There's no universal blueprint for how someone should act during an investigation. That said, in a forensic context, Nathan's behavior did raise questions. His earlier reluctance to come in, like repeatedly avoiding contact with the investigators, followed by a sudden display of ease once in the interview room, is a pattern that does suggest possible impression management.

• 20:57Tristin Engels?

  Investigators are trained to note these shifts because they can speak to how an individual's navigating pressure, not just whether they're feeling it. With that in mind, his calm joking demeanor could reflect several things. It might indicate emotional detachment. Or an ability to compartmentalize stress. It could also suggest a strategic attempt to appear cooperative and non-threatening, which is a behavior we sometimes see in individuals who want to control the tone of the conversation. In certain cases, it can align with traits like narcissism or with superficial charm, especially if the person believes they can steer perception or outmaneuver the suspicion of investigators. So while Nathan's behavior in the room wasn't inherently incriminating, it stood out,

• 21:40Tristin Engels?

  not because he was calm, but because of the contrast between that composure and his earlier avoidance. And because of what it might suggest about how he relates to stress, scrutiny, and control in high-stakes situations.

• 21:54Vanessa Richardson?

  Nathan wasn't the only one keeping his composure. When Shauna was questioned, investigators found that she was cool, calm, and collected as well. But there was one thing that bothered them. Nathan and Shauna's versions of what happened that day were so identical, it seemed coordinated. The authorities were still waiting for some forensic tests to come through. The blood from Becky's bedroom door frame, along with the fingerprint, were still being analyzed. But given Nathan's nonchalant attitude during questioning and his possible collusion with Shauna over their stories, investigators were getting suspicious. So a few days later, just before the end of February, Nathan was called back to the station for more questioning.

• 22:39Vanessa Richardson?

  He still came off as cooperative and relaxed, but at some point during the interview, he let something slip. He told the police he didn't like Becky, and he resented how she treated his mom. He said it so matter-of-factly that it's unclear if he was even aware of how important this was to the investigation.

• 23:00Tristin Engels?

  So first, that could very well have been a subconscious slip. In investigation interviews, especially after repeated questioning, people sometimes reveal underlying emotions or beliefs without realizing how significant that disclosure is. In Nathan's case, he may have become desensitized to the weight of what he was saying. Like, it no longer felt like a confession, rather, it felt like a truth he had told himself so many times that it no longer registered as incriminating to him. That said, there's also another possibility. This could have been a calculated attempt at a partial disclosure, like a way of releasing controlled information to investigators. By giving a selective truth, he may have done this to appear honest. It's also possible that Nathan made this admission

• 23:44Tristin Engels?

  out of a sense of confidence or perceived rapport, believing he'd established a friendly dynamic with the investigators after several interactions. Interviewers often adopt a non-confrontational conversational approach to encourage disclosure, and individuals in Nathan's position may interpret that tone as genuine camaraderie, which could lead them to reveal more than they intend to. Whatever the reason, this kind of admission is actually very relevant to an investigation because it could establish a motive.

• 24:17Vanessa Richardson?

  Whatever Nathan's reasons were for telling the police how he felt about Becky, he essentially handed them a motive on a silver platter. After that interview, they started looking at Nathan as the primary suspect, with Shawna as a possible accomplice. They seemed to already have at least Nathan's fingerprints on file, likely taken at some point during one of his interviews. So at this point, they were just waiting for the forensics to come back and confirm their suspicions. Soon, they got their wish. The results confirmed that the bloody fingerprint was indeed Nathan's, and the blood it had been smudged in was Becky's. On February 28th, the police arrived at Nathan and Shawna's home

• 25:01Vanessa Richardson?

  and placed them both under arrest for kidnapping. It had been eight days since Becky was reported missing, and the authorities were still hoping she was alive. Once the couple was brought back to the station, they were questioned separately. They knew Shawna was more articulate than Nathan, and their approach with her was to keep her talking as much as possible. They hoped she'd eventually reveal a clue that led to Becky's whereabouts. But she didn't. She just said Nathan had nothing to do with it. When it came to Nathan, the detectives tried a different tactic. They knew from questioning him earlier that he liked to feel in control. So in order to take the power out of his hands,

• 25:43Vanessa Richardson?

  they made sure he knew that they had evidence against him. Meanwhile, police teams combed over Nathan and Shawna's house to look for signs of where they were keeping Becky. As soon as the investigators entered the home, they could see how filthy it was, like a hoarder's almost. But when they got to the upstairs bathroom, they noticed something odd. The bathtub was incredibly clean. It was an anomaly in an otherwise unlivable house. And when they scoured the rest of the place for more evidence, they found a pile of it in the attic crawl space, a wad of receipts for the circular saw and the other supplies Nathan bought to dispose of Becky's body.

• 26:27Vanessa Richardson?

  When detectives looked at those receipts and saw what Nathan had purchased, they knew this was no longer a kidnapping. It was a murder investigation. The authorities went back to the station, and the detectives then presented this evidence to Nathan. That's when he realized he was caught. On March 2, 2015, through a prepared statement by his lawyer, Nathan admitted to murdering his stepsister Becky Watts. However, he claimed he hadn't planned to kill her. Nathan said it happened in a moment of panic. His mask slipped and Becky saw his face, so he just instinctively reacted. When asked about Shawna's role in Becky's death,

• 27:11Vanessa Richardson?

  Nathan said she didn't have anything to do with it. According to him, Shawna didn't even know about it.

• 27:19Tristin Engels?

  It's not entirely unexpected or even uncommon that Nathan confessed. Individuals confess for a variety of reasons, and it's rarely out of guilt or remorse. In cases like this, a confession may reflect a strategic response to overwhelming evidence. So, for example, when a suspect perceives that there is no viable path to continuing denying it or escaping it, they may choose to confess in order to regain a sense of control, minimize the consequences, or in some cases, protect someone else. In Nathan's case, I think it was to regain control, protect his image, and it was self-serving.

• 27:56Vanessa Richardson?

  Well, it really seemed like the dam had burst because during Nathan's confession, he also gave detectives the piece of information they wanted the most: where Becky was. Investigators then went to the shed where Nathan had hidden everything. The sight of Becky's remains meticulously wrapped in plastic bags was horrific. But as gruesome as it was, it also gave the authorities hope because in that shed, they had everything they needed to hold Nathan Matthews accountable for his crimes.

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• 30:30Speaker 07

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• 30:37Vanessa Richardson?

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• 30:51Vanessa Richardson?

  On March 2, 2015, 28-year-old Nathan Matthews admitted to killing and dismembering his 16-year-old stepsister, Becky Watts. When news of his arrest got back to their family, there were a few different reactions. No one knew about Nathan's confession yet, so Nathan's stepdad, Becky's father, Darren, actually thought investigators had it wrong. They didn't, but there was still a long way to go before Nathan was brought to justice. In particular, authorities wanted to know if he was lying about Shawna's involvement.

• 31:28Tristin Engels?

  So objectively, it's not uncommon, but it is notable that Nathan did not attempt to deflect blame onto Shawna when he confessed. Given his treatment of Shawna and his pattern of callousness, even I actually expected him to implicate her in order to save himself. But the reality is, in some cases, suspects in relationships where there's intimate partner violence engage in protective behavior, especially if they view their partner as dependent or subordinate. Or they had some kind of investment in the relationship that they want to preserve. In Nathan's case, I'm inclined to believe that it's calculated self-interest. As long as Shauna serves some kind of function for him, he wants to maintain

• 32:10Tristin Engels?

  control of her and keeping her safe from prosecution in his mind means he maintains her support in different ways, and he will need that support where he knows he's likely headed.

• 32:22Vanessa Richardson?

  That is so fascinating. What does it say about Nathan that he was able to both harm and protect?

• 32:29Tristin Engels?

  So that once again speaks to his capacity to compartmentalize not just emotions, but even morality, but also his continued need for control, control of image, the narrative, his relationship, and the investigation. It's certainly possible, too, that he had a genuine attachment to Shauna. There was at a minimum a trauma bond between them, but as the abuser, they often equate ownership with loyalty. So showing his devotion and loyalty allows him to maintain his sense of ownership and control. And like I mentioned previously, when it comes to individuals like Nathan, their actions are often selective and self-serving. On the outside, it may appear like he's experiencing love or remorse,

• 33:10Tristin Engels?

  even protectiveness, but in truth, it's all for his own self-interest. Protecting Shauna means outside support. It means financial support, emotional support, and psychological support. He's losing control over everything, especially when he goes to prison. So right now, the last thing he has control over that he's maintaining is Shauna. So someone like Nathan will want to maintain that however he can, and we've seen how, what lengths he will go to in order to keep that control.

• 33:41Vanessa Richardson?

  On March 3rd, one day after Nathan's confession, Shauna was questioned again. She maintained her innocence. She said she hadn't known what Nathan did until his confession the day before. But the authorities weren't convinced. They searched the couple's phones and computers and found the violent texts they shared, along with the child sex abuse videos they watched. After the computer seizure and almost 100 hours of questioning, Nathan was officially charged with murder and put into custody. Shawna was charged a few weeks later, when they connected her DNA found on the face masks and bags that were taken from the shed where Becky's body parts were found.

• 34:24Vanessa Richardson?

  Nathan and Shawna went on trial together about seven months later, in October 2015. The evidence was hard to stomach. Along with having to confront the devastating state Becky's body was found in, the jury also heard detailed analysis on what could have driven Nathan and Shawna to pull off such a heinous crime. Much of Shawna's portion of the trial was dedicated to her being an abuse victim, controlled by Nathan's physical and psychological torment. But David Wilson, a professor of criminology at Birmingham City University, thought there was something else at play with the couple. He suggested that Nathan and Shawna suffered from a form of shared madness called folie a deux.

• 35:09Tristin Engels?

  So yeah, let's talk about folie a deux. That's a term I haven't heard in a long time, and it's a French term that stands for, like you mentioned, madness of two. Clinically, it refers to a very rare psychiatric syndrome where two or more people share the same delusional beliefs, typically within a close, isolated relationship, such as between romantic partners, siblings, a parent, and a child. It's also known as shared psychotic disorder, or shared delusional disorder, in the psychiatric realm. I've always known it to be referred to as shared psychosis. While folie a deux is rare, it highlights how dysfunctional dynamics and psychological dependency can distort reality, especially when one person has an influential or coercive

• 35:54Tristin Engels?

  role. It's most relevant in forensic settings when trying to understand co-offender dynamics, or cases where one partner seems to participate in harmful behavior. You're under the influence of another's delusional or dominant thinking. That being said, it's no longer in the Diagnostic and Statistical Manual of Mental Disorders as a standalone diagnosis. It was removed in 2013 and folded into broader categories of psychotic disorders. I understand why this comparison was proposed. The dynamics between them definitely bear the resemblance there. But they did not appear to meet the full criteria from what we know here. Obviously, I've never evaluated them, so I'm not saying with full certainty. But from what we've outlined, there doesn't seem to be clear evidence that Nathan held

• 36:39Tristin Engels?

  a primary delusional belief, or that Shawna adopted it. Simply being fixated on Becky, or displacing anger onto her because of jealousy, or unprocessed rage, does not necessarily rise to the level of a clinical delusion based on that information we have. What this reflects more accurately, in my view, again, based on what we know, and something I've seen frequently when evaluating women who are co-offenders in a case with their male partners, is their behavior is often driven by the need to appease their dominant partner. This stems from a combination of factors like fear, psychological dependency, coercion, isolation, trauma bonding, and sometimes substance abuse.

• 37:21Tristin Engels?

  That's very different from shared delusions or psychosis. Coercive control can gradually diminish a person's autonomy over time, creating a sense of emotional captivity, where the victim becomes increasingly compliant, disoriented even, and are unable to set boundaries, and unable to do so safely. And we cannot overlook that Shawna was still a child when she met Nathan. That early exposure means there was grooming involved, which most certainly set the stage for long-term and total control, especially now that they have a child that Shawna was likely also wanting to protect. So now, I say all that to provide context, to help understand co-offender dynamics, not to minimize Shawna's culpability.

• 38:04Tristin Engels?

  Because at this point Shawna is an adult, and from what we know is of sound and rational mind. She knows right from wrong, and she could have found safe ways to leave this abusive situation, to protect her and her child. Nathan's mother is an example that that is possible.

• 38:21Vanessa Richardson?

  It was certainly an interesting argument. And when the five-week trial ended, the jury deliberated for 3 hours and 27 minutes before finding Nathan guilty of murder. Shawna was convicted of manslaughter. When the verdicts were read, there were audible gasps of relief from the people in the courtroom. Nathan bowed his head, while Shawna just stared into space, wiping tears from her eyes. Nathan was sentenced to life in prison with a minimum sentence of 33 years. Shawna got 17 years. Some believed the punishments were far too generous, at least when it came to Nathan. Darren, Becky's dad, thought his stepson,

• 39:06Vanessa Richardson?

  who was the best man at his wedding, deserved the death penalty. But that didn't mean Darren abandoned Nathan's mother. He and Angie stayed married and supported each other through this turmoil. But Angie did have a long road ahead of her. She had to reckon with loving her son while also accepting what he'd done, which seems like an impossible thing to process, because what Nathan did feels so inexplicable. Both Becky and Nathan were raised in similar circumstances. They had to contend with being raised in a blended family and struggled to connect with others. But while Becky rose above it, Nathan let his troubles consume him.

• 39:51Vanessa Richardson?

  And as a result, he destroyed both of their lives.

• 40:11Vanessa Richardson?

  Thanks so much for listening. Come back next time for a deep dive into the mind of another murderer.

• 40:17Tristin Engels?

  Killer Minds is a Crime House original powered by Pave Studios. Here at Crime House, we want to thank each and every one of you for your support. If you like what you heard today, reach out on all social media at Crime House. And don't forget to rate, review, and follow Killer Minds wherever you get your podcasts. Your feedback truly makes a difference.

• 40:37Vanessa Richardson?

  And to enhance your listening experience, subscribe to Crime House Plus on Apple Podcasts. You'll get every episode of Killer Minds ad-free, along with early access to each thrilling two-part series and exciting bonus content. Killer Minds is hosted by me, Vanessa Richardson, and Dr. Tristin Engels, and is a Crime House original powered by Pave Studios. This episode was brought to life by the Killer Minds team: Max Cutler, Ron Shapiro, Alex Benadon, Lori Marinelli, Natalie Pritzowski, Sarah Camp, Kate Murdock, Seth Bloger, Lea Roche, and Carrie Murphy. Thank you for listening.

• 41:25Vanessa Richardson?

  If you're looking for your next podcast, check out What the Fact with Connor Tomlinson from Netflix's Love on the Spectrum and Carter Roy. Every week, they take three unbelievable true facts from history and tell you the full story behind them. Follow What the Fact wherever you listen, or subscribe on YouTube at What the Fact Pod.