Science Vs - Serial Killers: The Mind of a Murderer

Episode Date: May 5, 2022

[REBROADCAST] What makes a serial killer? What drives them to kill again and again? To find out the truth about this ghastly lot, we talked to forensic psychologist Prof. Eric Hickey, criminologist Ass. Prof. Wayne Petherick, and psychiatrist Prof. Gwen Adshead. Find our transcript here: https://bit.ly/39HcSsv Note: in this episode we discuss homicide, and sexual violence. Please take care when listening to the show, and here are some resources: National Mental Health Helpline: 1-800-662-HELP (4357). National Hotline for Crime Victims: 1-855-4-VICTIM (1-855-484-2846)  National Sexual Assault Hotline: [phone]-HOPE (4673) Learn more about your ad choices. Visit podcastchoices.com/adchoices

Hi, I'm Wendy Zuckerman and you're listening to Science Versus from Gimlet. And a quick warning before we get started. In this episode, we'll be discussing homicide and sexual violence. So please take care when you're listening to the show. And if you're feeling depressed or you just want to talk to someone in the US, you can call the National Mental Health Helpline, which is at 1-800-662-HELP. So that's 1-800-662-4357. We'll pop it in the show notes. Okay, let's jump in. This is the show that pits facts against foul play. On today's show, serial killers.

One murderer who embodies a lot of our fears about serial killers is a guy named Ed Kemper, who killed his victims in the 60s and 70s. Can you tell us about Ed Kemper? Oh, yes. Oh, yes. I can tell you about Ed Kemper. And by the way, you would like Ed, and he would like you. Because I'm female? Yes, and he would probably kill you. The guy telling us about Ed Kemper is a researcher called Eric Hickey. He's a criminal psychologist at Walden University and knows a lot about serial killers. And he told us that Ed started killing early, when he was only 15. He said, one day I just came down for breakfast. I just thought, what would it be like to shoot

grandma and kill her? So he walked up behind her with a rifle and shot and killed her. He killed his grandfather too. And then Ed turned himself in. He ended up in a state psychiatric hospital. In the late 1960s, he was released on parole. And by now, he's 21. He's grown up and back in the outside world. And he looked kind of dorky and unassuming. He wore these thick glasses, but was really smart. And he was huge.

He's 6'9", 300 pounds. He's a big guy. And it didn't take long before this big guy started getting violent again. In May 1972, he picked up two young female hitchhikers who were asking for a ride. And Ed was charming. They would get in the car because he was such a nice guy and then you take him off in the woods and you would kill them. And after these two women, Ed kept going. Kemper was killing college students as fast as he could. Oh, my God. He killed four more young women within just a few months.

And all the while, he was living what appeared to be a perfectly normal life. Even his psychiatrist was fooled. Eric told us this one story about when Ed visited his therapist. He's sitting down and the therapist started telling him about how pleased they were with the progress he had made. Then he looked at the therapist and said, well, without you, I wouldn't be here. And he thanked the therapist for all their help. During that interview, in the parking lot, in Ed Kemper's car, in the trunk of his car, was the head of a college student. Yeah, Ed often decapitated his victims and kept the heads. On occasion, he actually had sex with them.

The heads. In total, Ed Kemper murdered 10 people, including his mother, before again turning himself into the police. And Ed Kemper, he's our monster. A cunning predator who lures women into traps. He's so quintessential as a serial killer that there's a character based on him in the TV show Mindhunter. And the creepiest thing about it is that while Ed is now in prison, there are other serial killers out there right now. And we are kind of obsessed with them. It seems like every year we get a new batch of TV shows about these guys. Last year, there was a big doco on Ted Bundy. And one of the most popular

Netflix shows in the US right now is a new documentary about John Wayne Gacy. So today on the show, we are revisiting one of our most popular episodes on the science of serial killers, where we ask, what do we really know about them? In the movies and these TV documentaries, they're often portrayed as being these super smart killers that leave signature calling cards wherever they kill. But is any of that true? And what can science tell us about what really makes a serial killer? Like, how do these people just wake up one morning and think, I'm going to kill? When it comes to serial killers, there's lots of...

I just thought, what would it be like to shoot grandma? But then there's science. Science vs. Serial Killers is coming up just after the break. It's season three of The Joy of Why, and I still have a lot of questions. Like, what is this thing we call time? Why does altruism exist? And where is Jan 11? I'm here, astrophysicist and co-host, ready for anything.

That's right. I'm bringing in the A-team. So brace yourselves. Get ready to learn. I'm Jan 11. I'm Steve Strogatz. And this is... Quantum Magazine's podcast, The Joy of Why.

New episodes drop every other Thursday, starting February 1st. What does the AI revolution mean for jobs, for getting things done? Who are the people creating this technology and what do they think? I'm Rana El-Khelyoubi, an AI scientist, entrepreneur, investor, and now host of the new podcast, Pioneers of AI. Think of it as your guide for all things AI with the most human issues at the center. Join me every Wednesday for Pioneers of AI. And don't forget to subscribe wherever you tune in. Welcome back. On today's show, we're finding out what do we really know about serial killers? Now, according to the FBI, you're considered a serial killer if you kill at least

two people in separate events. Researchers estimate that over the last two decades, there have been more than 600 serial killers scurrying around the US. Nine out of 10 of them are men. Now, when you look at serial killers in Hollywood, there's a few things that they often seem to do. I mean, other than killing people. And one of them is leaving some weird calling card. Hollywood often presents it as if the killer is playing out some creepy fantasy. Like in Silence of the Lambs, the killer puts moths in his victim's throat. And in The Mentalist, the serial killer would always paint a smiley face in the victim's blood, somewhere near the crime scene.

Drawn in the victim's blood, clockwise with three fingers of his right hand, wearing a rubber kitchen glove. And then in The Wire, just to imitate a serial killer, McNulty tied red ribbons to several dead men. Wayne Petrick, a researcher of criminology at Bond University in Australia, told us, you just see this trope everywhere. Oh, it's absolutely repeated sort of ad nauseum in television shows and movies on serial killers. So in the real world, is this calling card thing true? Well, to answer this question, Wayne told us about this one study

of 90 serial killers that looked into this very question, analysing the stuff they did other than killing. And basically, the researchers wanted to know... Did they steal something from the crime scene? Were there bite marks, for example? Did they disfigure the body or engage in other mutilation behaviours? So, other than killing them, the most common thing that serial killers did to their victims was sexually assault them.

There was other stuff in the data too, though, like dismembering their bodies. The researchers found that 40% of the time, these serial killers dismembered their victims and about 30% of the time they scattered their body parts. But Wayne says that this isn't necessarily because they're playing out some weird fantasy. It could be that maybe they just wanted to kill someone and now they're covering their tracks. So you might dismember a body because it's some fantasy that you have or you might dismember a body to help you dispose of the body. Wayne says, as a rule of thumb,

before you start thinking that this is some fantasy, ask yourself, could it be functional? Still, though, it's clear that not everything that serial killers do is functional. A study of almost 40 serial killers using data from the FBI found that 70% of them did some things to their victims that would be very hard to explain. Things like carving a pattern into the victim's chest or leaving them in weird poses. What the movies get wrong, though, is that most serial killers don't seem to do the same weird thing to their victims every single time they kill. And several studies have found this.

More often than not, they switch it up. Those kinds of signature behaviours don't tend to occur with as great a frequency as we're led to believe. In fact, there's this popular idea out there that cops might be able to catch serial killers by looking at crime scenes and finding patterns. Think Mindhunter or Jodie Foster in Silence of the Lambs. But this usually doesn't work. A study of 200 serial killers actually found that the most common way for one to get caught was because someone they knew turned them in.

Another common way, they were arrested for something else, like Ted Bundy was caught driving a stolen orange Volkswagen Beetle after his final murder. And you know, movies would be a whole lot shorter if Hollywood cops didn't go around analyzing their creepy calling cards, but instead whipped out an old-fashioned map. And that's because science has found that most serial killers tend to kill where they live or work. Seriously. Researchers have found that, as a good rule of thumb, if you take the sites of the two crimes that they did that are the furthest away and then draw a circle around them, the culprit's base will likely be inside that circle. A recent study looked at this for 15 convicted serial killers in Brazil

and it showed that two-thirds of them were found in that circle. So, bottom line, forget the red tape or moths in your throat. I think that the idea that every serial killer leaves like an ace of spades playing card behind at a crime scene is very different from the reality, which is that they are really just somebody who is inclined to kill multiple times. They're just someone who's inclined to kill multiple times. They're just someone who's inclined to kill.

Multiple times. Our next question is, what's that about? Because for many of us, the idea of killing someone is not something we want to do on a Tuesday night. And yet, serial killers do this over and over again. And in the movies, they seem to have some important reason for doing it. Perhaps a big master plan. Like in the recent Batman, the Riddler wants to expose a ring of corruption. The doomsday killer in Dexter is trying to bring about the end of the world.

John Kramer from Saw technically killed people to show the value of their life. So in real life, why do they do it? Well, to get at what drives serial killers, we went back to our criminal psychologist Eric Hickey, who we met at the beginning of the show. He's the guy who really enjoys his research into

serial killers. I just really like the dark side because I need to know what people are like, what makes them tick. And Eric is kind of the perfect person to talk to about why serial killers do what they do. He's analyzed hundreds of cases and interviewed about a dozen serial killers personally. Like, he told us about this one guy, Larry DeWayne Hall.

He's believed to have killed dozens of women in the 80s and 90s. So the two of them, Eric and Larry, sat and talked. I'm sitting with my leg. My right leg is touching his left leg. That's how close I am to Larry. And Larry looks like something out of a horror movie. And he's got this long beard and he's got this crazy look in his eyes.

And at first, it wasn't clear why Larry had killed so many women. That was until Eric asked him. He said, so Larry, do you have a girlfriend? Have you ever had a girlfriend? Have you ever had sex with a woman? He goes, no, never. So now the big question was, the million dollar question was next. I said, Larry, have you ever had sex with a dead woman?

And he looked at me and he sort of smiled and goes, well, maybe. Larry was killing his victims. And as soon as he killed them, he had sex with them because they were still warm. So to them, him, it was like they were still alive. Right. A lot of serial killing seems to be sexually motivated. As we said, a lot of serial killers rape their victims before killing them, while some of them, like Larry, have sex with them afterwards. And although necrophilia in serial killing is rare, it's hardly unheard of. It's not always about sex, though. Some serial killers do it for good old-fashioned greed. In one large serial killer database, almost a third were found to have killed for money. In fact, this seems to have

motivated America's first known serial killer. It was this guy called Herman Mudgett. In 1886, he moved to Chicago and became a pharmacist using the name Dr. H.H. Holmes. Soon after, he apparently began killing people to steal their property. The building he killed in became known as Murder Castle. It was reported that in the corner of the cellar, there was this creepy vault where Herman dissolved his victim's bodies in quick

lime. So, some serial killers do it for money. But two large surveys found that the most common reason is because they get some kind of enjoyment out of it, sexual or otherwise. Like the Zodiac killer who killed at least five people. He wrote, I like killing people because it is so much fun. So what made serial killers this way? How do you become someone who likes killing because it is so much fun? That answer, after the break. Welcome back. So today on the show, we're going through the Hollywood tropes of serial killers, slicing them up one by one.

And our next victim, the evil genius trope. Okay, so one idea from the movies is that serial killers are intelligent masterminds who get off on killing because they see themselves as higher up on the food chain. The rest of us are like prey scurrying around for them to catch. Like, here's Kevin Spacey's character describing how he saw his victims in the movie Seven. An obese man, a disgusting man who could barely stand up. And after him, I picked the lawyer, and you both must have secretly been thanking me for that one.

Only in a world this shitty could you even try to say these were innocent people and keep a straight face. And this idea of serial killers as evil geniuses preying upon weaker victims, it shows up in true crime docos all the time. Malicious masterminds. They are among the most devious and twisted of killers. Their intellectual acumen is their greatest weapon.

It enables them to plot elaborate crimes and elude capture. So, to find out if this is true, reporter Shruti Ravindran spoke to Gwen Adseth, who is now a forensic psychiatrist and psychotherapist in UK prisons and psychiatric hospitals. And Gwen has been working with murderers and violent offenders for more than a decade. I have to ask, when you find yourself sitting next to a very chatty person on a plane, what do you tell them you do? Ah, well, I don't usually tell them what I do. I usually tell people I'm a florist. Why a florist? Why a florist? Well, I love flowers and I'd love to be a florist. And talking about flowers is usually preferable to talking about murder and violence.

But for this episode, we prefer to talk about murder and violence. And in particular, whether serial killers are smarter than the rest of us. People think that serial killers are these super evil geniuses that are just like diabolically intelligent. Yeah. What do we know about whether that's true? Well, we don't have any evidence that that's true. Most of the people who've been identified as serial killers have been of average intelligence. Gwen told us about this one database where researchers had gathered together the IQ scores of more than 300 serial killers, mostly from the US.

And while IQ is not a perfect measure of intelligence, it's one of the best we've got. So here's what the researchers found. Most of these serial killers are about as smart as you and me. On average, probably a little dumber. Another study on German serial killers also found that, generally speaking, they're not a bunch of geniuses. Now, there are some super smart serial killers, like Ed Kemper, the guy with the head fetish.

He was said to have an IQ of around 140. That's just shy of genius level. But he is the exception rather than the rule. The idea that there are a lot of evil geniuses running around plotting to kill people is not really borne out by the data. Okay, so here's what we know so far. Most serial killers aren't leaving bizarro calling cards around or executing big smarty pants master plans. Mostly they're killing because they get some enjoyment out of it. The next question we want to jump into is how did they come to be like this? In the words of Lady Gaga, were they born

this way or did something happen to them to set them on this path? Which brings us to this idea that people reach for a lot to explain serial killers' behaviours. And it's that these killers are born psychopaths. It's a word that gets thrown around a lot, but a big thing here is that it just means these people have a lack of empathy. That is, they seem normal, but they can hurt people without remorse because they don't feel bad when others suffer.

And Hollywood? It loves a good, emotionless serial killer. Think about Christian Bale. Like, seriously, just think about Christian Bale. I mean, his character in American Psycho. I have all the characteristics of a human being. Flesh, blood, skin, hair. But not a single clear, identifiable emotion.

Except for greed and disgust. Not a single emotion. But when documentary filmmakers asked Ed Kemper about this idea in the 1980s, he said that he did feel bad, especially when it came to killing his own mother. I looked at her, I said, no, I said, goodnight. And I knew I was going to kill her. You know? It hurts. Because I'm not a lizard.

I'm not from under a rock. And what is super creepy here is that many serial killers are fully functioning members of society who don't suffer from any obvious psychological disorders. That is, until they're found killing a bunch of people. Like one study of more than 250 serial killers found that only about 20% of them were diagnosed with a psychiatric disorder before getting caught. The notorious BTK killer, Dennis Rader, who taunted law enforcement for three decades, was married with two children, a respected member of his local church,

and even a Cub Scout leader. That was while he was murdering women. So, why do they do it? Is it because they can't feel other people's pain? Well, studies have actually looked at the relationship between having low empathy and being violent. And they can't really find a strong, obvious link here. To suggest that you're generally low in empathy

on a day-to-day basis in your social relationships, I think the jury is pretty out on that one because there are different studies show different things. In fact, it's not even true that most serial killers are psychopaths, which is a disorder that is characterized by having a lack of empathy. A recent study asked more than 60 serial killers to fill out a psychopath survey. Seriously, it asks you to rank on a scale of agree to disagree with statements

like, success is based on survival of the fittest, I am not concerned about the losers, or for me, what's right is whatever I can get away with. And on average, serial killers didn't ace the test. It turned out they weren't any more likely to be psychopaths than you or me. Now, there are a batch of different studies where scientists have tried to get at this question in a different way, by peeking into the brains of killers to see if something's odd in there. And some researchers have argued that they can see differences in the brains of some violent people and murderers, like that they have abnormalities in their prefrontal cortex, which might signal that they have less self-control, maybe less empathy. And you're a

scientist called Jim Fallon wrote a book about this. But in Jim's work, he said that the brain scan with the biggest so-called psychopath signature was his. Now, interestingly, while one of Jim's cousins is Lizzie Borden, 40 Wax Lizzie Borden, it's a distant cousin. He's also related to ezra cordell the founder of cornell university and what jim's story tells us is that while some serial killers might have something a little off when they're born this can't explain everything or as jim put it in an interview quote it shows that your genes are not a jail sentence. So if there's a bit of nature to blame here, what else do we have? One kind of remarkable study looked at this very question, trying to figure out what killers have in common.

They looked at more than a thousand juvenile offenders, comparing the ones who had committed murder to those who had committed some other crime. And so-called psychopathic tendencies, lack of empathy, being callous, that didn't predict whether someone would kill. What the study did find, though, is that kids who grew up around violence, that is what increased their chance of becoming a killer. And Gwen suspects this is true for serial killers as well. I mean, I think it's very likely that a man who becomes a serial killer is likely to have been exposed to violence in childhood. I think it's quite difficult to just start up a career of violence without having been exposed to it in some way.

And this takes us to the most concrete clue that we could find in the literature to help explain serial killers. They have a higher chance of being abused as kids compared to other people. One study of 50 serial killers found that about two-thirds had been abused, and that includes all kinds of abuse, physical, sexual and psychological. Another analysis of 100 serial murderers found that more than half had experienced, quote, parental brutality.

This is true for Ed Kemper, the guy with the heads. He's said to have grown up in an abusive home. His mother would lock him in the basement for hours as punishment. And there's other ideas out there about what went on in the childhoods of serial killers. Like that they tortured animals, wet the bed and lit fires. If you've heard of these ideas, they all come from one dude. Old McDonald. Well, John McDonald. In 1963, he wrote a paper about psychiatric patients,

noting that the very sadistic patients had done these three things as children, were cruel to animals, set fires, and wet the bed. And you can find evidence for some of this stuff in the literature. Not so much the bedwetting, but like, Ed Kemper was really into animal torture. When he was a kid, he took the family's cat, buried it up to its neck, and then decapitated it, keeping the head as a trophy. I know. That's why they called him Hetty Yetty. Not really. But Gwen says that many people have obviously had really terrible childhoods and never killed. And bottom line, no matter how much true crime you watch or listen to,

what makes someone a serial killer is still very much a mystery. I think that one of the myths about serial killers is that we know a lot about them. And I'm not sure we do know a lot about them because they're so unusual. They're statistically just off the map. Serial killing is so rare that it's estimated to account for less than 1% of all homicides.

And the fact that they're so outside the norm makes it really tough for science to explain what's going on. But here's what we do know. Most serial killers are men who rape and brutalize their victims before they kill them. And some rape them after they kill them too. And at the end of the day, when we sensationalize serial killers, turning them into intellectual masterminds with calling cards and grand plans,

we elevate them from murderers into celebrities. And, you know, your chance of being taken out by a serial killer is obviously very small. Like if you're a woman, statistically, you're way more likely to be killed by a current or former male partner than anyone else. But we don't think about that. We would much prefer to think about the homicidal equivalent of ghoulies and ghosties, those strangers or weirdos or people with a funny walk or an IQ in the thousands. So I think that these are distractions. I think we would rather look at stories

than we would like to look at the reality. Yeah, because reality kind of sucks. But if you need to forget about your woes for a while, why don't you try watching ASMR videos instead? Hello. Hello. Today I wanted to show you another tutorial on how to fold towels. And the science of that is coming up next week on Science Versus. This episode was produced by Shruti Ravindran, Meryl Horne, Rose Rimla, Caitlin Sorey, Courtney Gilbert, Michelle Dang and me, Wendy Zuckerman.

We're edited by Blythe Terrell. Additional editing help from Alex Bloomberg. Fact-checking by Michelle Harris and Diane Kelly. With music by Bumi Hidaka, So Wiley, Bobby Lord and Emma Munger. Sound design and mix by Emma Munger and Bumi Hidaka. A big thanks to all the researchers who helped us out with this episode, including Dr. Mike Amott, Dr. Anne Burgess, Dr. Scott Lillianfield, Dr. Devin Polishek, Dr. Corey Ryan, Dr. Kim Rosmo, Dr. David Finkelhor,

Dr. David Keatley, Dr. Jennifer Lansford, Dr. Karen Franklin, Dr. Michael Maltz, Dr. Gabrielle Salfati, Dr. Claire Ferguson, Dr. Sandra Taylor, and Catherine Ramsland. I'm Wendy Zuckerman. Back to you next time.