Serial killers are not born criminals but develop their violent tendencies through a combination of biological predispositions (approximately 30%) and environmental factors, particularly childhood trauma and failed relationships (approximately 70%); understanding these psychological patterns through case studies of notorious killers like Jeffrey Dahmer and the Unabomber helps researchers develop prevention and intervention strategies, as most serial killers lack empathy and form attachments to victims through fantasies rather than genuine emotional connections.
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What Drove Jeffrey Dahmer to Kill? Forensic Psychologist Explains | Minutes With
Added:He had a table in his in his living room. And on that narrow long table, I believe, he had placed eight heads of his victims, eight different heads.
These were his favorite victims. And in front of the table, he had placed a large black chair. His goal was to be able to sit down in that black chair surrounded by his friends who could never leave him. And finally he said, "I will feel powerful."
Finally, I'll feel powerful.
>> Who was the first serial killer that you interviewed and do you remember that interview?
>> Okay. The first one, oh my. So, I believe one of my very earliest interviews was with Randy Woodfield, the I-5 Killer. He had a very interesting MO.
How he would do his killings.
He was pretty handsome guy. He tried out for the Green Bay Packers before before he did killings. He was a football player. He got cut from the team. He became a serial rapist uh for a while. He didn't He didn't get caught.
Um and then he started going around and he would go to businesses uh at night in the evening when they're closing shop. For example, one one place he went to a a store, a small store, a flower shop and the the owner was in the back closing up the shop. And so he went back and uh he tied her up with duct tape.
And he'd done this to several victims before this.
And so he tied them up with with duct tape and put them on the floor on their knees and make make them He take a gun out and put them on the put the gun on their forehead and pull the trigger back. Four women, in three cases they did not kill.
And I And I heard about this through my one of my friends. I said, "I need to know why he didn't kill them." And I I went to the first victim who owned the flower shop. And I said, "So, by So, he has you in the back room.
You're You're tied up with duct tape.
You're on the on the floor. He's got a gun on your forehead with the trigger pulled back.
You know who he is now because you know he's already killed several females before you.
So, you know you're about to die."
I said, "Were you afraid?"
And she goes, "I was terrified."
I said, "So, why didn't he kill you?"
Now, I knew I knew why.
And I want her to tell me why.
I said, She said, "Well, I did exactly what he said." I said, "Yes. And did you cry and beg for mercy?" "No. I just did exactly what he said." And that's why you're alive today.
Because you did exactly what he said.
You didn't show fear. All four women were the same way. In one case, there were two females. And they made jokes with them. They didn't show fear.
So, why bother killing them?
He He had to have that fear factor. That was a fascinating experience. So, then uh I went interviewed Randy Woodfield, the I-5 Killer.
And it was a Again, uh it was a learning experience.
I sat in the interview room for 45 minutes waiting for him.
And I finally asked the guard, I said, "Where is he?"
Well, he's sitting on his bunk.
He knows you're here.
I said, "Okay. This is a This is a game.
This is the game. And And I'm learning from the game." So, he wants to be in control cuz he doesn't know me, but I know him. So, he wants to show me that he's in charge.
Fine. No problem. So, I learned from that. So, he finally comes out and we had this 3-hour interview. He never once would admit that he did the murders.
Um Of course, I knew he did the murders.
But I I listened to him and I let him kind of rant on. Um And I learned about his narcissism.
He exuded narcissism. It was amazing. A true narcissist. He would respond to newspaper ads. He'd find women looking for men to talk to. And so he'd send them pictures of himself just in a G-string.
And he was signed Adonis.
Uh Apollo or Adonis and he'd send it out to them. And they'd ask them to send pictures of themselves back naked. And some women did. So he had this following.
You know, there's there's groupies that would follow him.
He was a handsome guy. That was him.
That was Randy Woodfield. He loved to manipulate. He still does. I mean he's still there in prison in Oregon State Penitentiary. I learned a lot from him.
Not only because he he wouldn't confess to me that he'd done the murders.
But the way he talked to me, the way he talked about other people gave me a lot of insight into what a narcissistic personality is all about.
>> Why is it important to interview serial killers?
>> Why is it important to interview serial killers? It is a rare crime, relatively rare crime.
Um The FBI said we probably have about 35 of them approximately in the United States. Yeah, probably. So it's a very small number.
But because we're fascinated by it, because it's so unusual, so there's been a lot of public interest in it. For me as a academic researcher, public as an academic practitioner, I need to understand the dark side so we can do prevention and intervention, so we can help law enforcement track them down and make arrests and do and stop them before they they kill people. We have to get past the the sensationalism of of this kind of work because it's We say, "You're a profiler." Yeah, I profile. I do profile. But I don't call myself a profiler. That's very Hollywood. Um I'm a person who wants to understand these people. To understand the psychology of offending, the psychology of violence. And and how do people get there? And so the the longer I've been in the field, the more we learn about where it comes from. You know, it's most of it, not all of it, probably most of it is is from childhood trauma.
And and where it go where it takes people. We've learned that men and women respond differently to trauma and how they have that trauma. And and some turn to violence and women tend generally tend not to turn to violence but they do other things. That's why we only have maybe 16% of serial killers are female.
Because they because women generally find other ways to deal with their trauma than than men.
Um and we're socialized differently.
So all these things that we learn about and so then we can debunk the myths about serial murder. When you really start to think about the victims and what happens to them you you realize this is horrific what what these people have done to these victims.
And and so it's it's not about glorifying these people at all.
>> Do you the serial killers that you meet and interview do they often have remorse for their crimes or for their victims?
Do they show that to you in those interview settings?
>> It's a really good question about serial killers is do they have remorse for their crimes? Necrophiles like Jeffrey Dahmer um have remorse.
Not because they've killed people. They don't they don't connect with the victims.
They have remorse for their lives that being wasted. Dahmer said he said my life was pathetic. He never talked about the victims because they cannot connect to the victims. They don't have that empathy. They lack empathy. That's one of the hallmarks of these people. They lack the empathy. They lack the ability to have attachments to people.
However with necrophiles none of them are psychopaths.
They're sociopaths.
Um so they're they're because they have a connection. They have attachments to bodies, right? Dead people. But they don't have emotional attachments to them.
Whereas like you have a domestic violence situation someone killed their spouse they may have loved that spouse.
They may they may hate them. But when you talk about peo- people are true psychopaths who kill then they don't have any connections at all. Sociopaths also are some are serial killers but they have connections, they have attachments to people.
So, the question is do they have any feelings about the victims? They never talk about the victims. They don't want to remember them. Um Yeah, they that's not that's not something in their in their bailiwick.
They don't have any interest or capability to really connect with with those victims.
>> You mentioned Jeffrey Dahmer. Let's talk a little bit about how you came to be involved in that case.
>> I talked a lot of people.
Especially people who I find interesting and look interesting and I get feelings about people and and so I'm I'm walking through a Macy's store one day and I see a I see a man and he looked very interesting and I and I had a feeling about him. I should speak to him.
And so I stopped. I paid attention to that feeling and I went over to him. I started talking to him and he was very polite. He's and I asked him where he's from. He says he was from Chicago. I said, "I'm going there next week on a case." I said, "What brings you to California?"
He said, "My mom tried to kill herself.
So, I came out here to take care of her." Immediately, I knew who he was.
I I don't know how I knew. I just knew who he was.
I said, "Oh my gosh, you're Jeffrey Dahmer's brother, aren't you?"
And he looked at me and goes, "I am. How did [laughter] you know that?" I said, "I didn't know. I just just now know what you are."
And and he says, "I am." We became friends.
For that week, I went to went to went to Chicago with him.
Spent my time with him. Interviewed him.
He was quite worried that he might become like his brother. He would go visit Jeffrey in the prison every week.
He says, "I love my brother." I said, "I understand you love your brother." He said, "And I'm worried." I said, "Don't worry. You're You're not going to It's a very different mindset that what you do." He says, "I go to church every Sunday.
I'm I'm I'm a good person." I said, "You don't have to worry." So, because of that interview, I had a chance to interview his mother and that interview was utterly fascinating. When I first went into her home, she said, "Dr. You, I've been been wanting to meet you for some time. I want you to know, first of all, that my son never tried to hurt anybody.
He killed them, but never tried to hurt them."
I said, "I understand. Absolutely. Yes, that's exactly what he did.
Because he wasn't interested in the suffering of the victims. He needed them to die so he could be with them.
Because that was his attachment to dead people. After he killed his victim, he didn't kill anybody for maybe 7 years.
I said, "I know, given given your son, Jeffrey, [clears throat] he had to been doing something bad during that 7-year period." At his trial, it never came out.
He never discussed it. He was never asked. And she said, "Well, yes, he was doing bad things, and he told me in confidence what he was doing.
And I've never told anybody, but I'll tell you now in confidence."
Well, now she's deceased. She is now deceased, and so was Jeffrey, and so was his father. They're all deceased.
So, I can tell you what he said. He would go He would get newspapers and look up young men who had passed, car accidents, illnesses, then he would go to the viewings of the bodies.
Then he'd go to the funerals.
Then he would go to the cemeteries when they were they were buried. And at night, he would try to dig them up.
Because he wanted to He wanted to lie with them. He wanted to be with them.
I said, "That makes perfect sense to where he was coming from, cuz he had fantasies." And so, this took me down another pathway of understanding these men's fantasies. Because when people do these interviews, a law enforcement psychologist when they interview people, they don't really get into their fantasies.
Law enforcement does not train to do that. And so, for me, it was important to understand their fantasies, cuz fantasies will help us understand where they've been, with are now, and where they're going to go. With Dahmer, then, it was fit to understand him.
Um And so, he was going to do some writing for me, Jeffrey was, but then he called his mother one one day, and he he said, "Mom, I don't want to be in prison anymore.
I know I'm too dangerous to be on the outside."
And I think it was 3 weeks later he was dead.
And he didn't fight back.
No. He was attacked by a man with a lead pipe in the prison. And he I'm sure he didn't fight back cuz he he he wanted to die. During that time, uh when I was researching him, I came to understand him a little little more, why he picked those victims, and what he was doing, um The public sees that he cannibalized and consumed 17 people. And that's what they think about. And yes, he did that, but there was a a process of getting to that point where he did those killings.
I think in the beginning, had the men he lured, young men he had lured from from gay bars, had they stayed with him and not left him, they would still be alive.
But after 2 or 3 days, I've got got to get get back to work, I go back to my family.
Um and that's when he said, "No, you're not leaving." He'd get them drunk, he would strangle them. And he It came to a point where it kind of got past that, where where he knew then it didn't matter whether they stayed or not, he's going to he's going to he's going to kill them. He had a table in his in his living room, a small Well, it's about maybe maybe 8 ft long. Um and on that narrow long table, I believe, he had placed eight eight eight eight heads of his victims, eight different heads. These were his favorite victims.
On one end was a fully articulated skeleton that he had cleaned off. The other skeleton he was going to put out there was in the bathtub still being cleaned off.
And in front of the table, he had placed a large black chair. His goal was to be able to sit down in that black chair surrounded by his friends who could never leave him. Cuz remember when he came home from school one day his mother was gone. He'd been abandoned. And he was with his father and he wasn't close to his father.
So now he's surrounded by his friends.
He says they can never leave me. And now they're physically part of me. I I've consumed them.
He says, "And finally he said, I will feel powerful."
Finally I'll feel powerful.
And then to feel powerful he had to control people.
And that's a that's a very dark place to be in one's life. The need to control but that's all about psychopathy, right?
So but Dahmer was not a true psychopath.
He was a sociopath.
And and he was actually just a mid-range sociopath. Like he was like a 20 like a low range. He was a 23 on the scale.
Why? Because he had attachments to Debbie. He still loved his mom. He still loved his mother.
>> Do you feel that people like Jeffrey Dahmer are born that way? Are they born with this kind of urge to commit terrible crimes or does it come through that upbringing?
>> Well, nature and nurture. We we should dispel some mythology here about nature and nurture. No one is born to be a criminal. However, we must not discount biology and genetics.
Um you can inherit certain things from your family line like temperament, mental illness. These things are passed on. Not everybody gets it in your family. Some people do, some people don't. There might be fetal alcohol syndrome. There may be um some hormone hormone imbalance. There there could be domestic violence when the when the baby in the room is being traumatized. These things they can predispose a person but they don't necessarily make someone kill anybody.
So I I think 30% is about biology and genetics.
The other 70% is about nurturing or the lack of nurturing.
And so, nature loads the gun and if and if there's not the proper nurturing or the lack of nurturing, then nature will I'm sorry, nurturing will pull the trigger. For example, I had a a a couple of grandparents come to me after a lecture I gave and they said, "So, we have a grandson. He's been setting fires. He's been harming animals and we're very worried about him." And I said, "So, well, how old is he?"
"Well, he's 15 years old." I said, "Well, where where is he?" "Well, he's in juvenile hall." I said, "Is he there for setting fires?" "No, no. He's up because he's been he's raped his sister twice."
Wait, wait, wait. Let's back up a second here.
Okay. You're concerned about him setting fires? Well, Dr. We know you're in a hurry. We have a question.
And I'm going to quote you their question.
Do you think our grandson is dangerous?
I said I said, "Not only is he dangerous, it's probably too late to help him. And the truth is, you're part of the problem.
You don't get it. You're part of the problem. You're here asking me this question if he's dangerous. Of course, he's dangerous.
And where is where are his parents?
They're not here.
If I had a chance to go into that home I I didn't, but if I had a chance to go into that home and and research that home, you could have found a lot of weird things going on in that family.
Um so, it's often people don't see it. They don't pay attention to it cuz they don't want to see it. They don't see it coming.
>> You've said that in your field of work, it's often a story of failed relationships.
>> Yes.
>> Broken families, which I thought was really interesting. It seems kind of relevant given what you just spoke about.
>> man once said that no success can compensate for failure in the home.
You can always have a career, but you can't always raise children.
And children are our most important resource that we have in society.
Um and if we damage children when they're young when they're supposed to be bonding, attaching to to their to their parents or to their guardians, if we damage that, those connections, then all amazing, terrible things can happen as they grow up if there's not interventions.
So, most of what I've learned is from the trauma that children experience in in childhood. If I could be in charge of the world for a day, I would reduce domestic violence.
Because we see these these horrific things coming out of families that have a lot of trauma in them.
We can't stop everything. But I think we have an obligation to reduce domestic violence. I think that's how the my mindset.
I can't do a lot of good, but I can do some good. And if if we can all do some good, we can help change the world for a better place.
I think one one of the most insightful case I ever worked on was the Larry Hall case who killed 36 college students, and he's in prison now. He come up with a list of 36 names of people he said he killed, all female.
And and that he agreed to help them find the bodies.
But the agreement was that he get to go home to visit his parents. I'm sorry, visit his mother.
Cuz there's never a dad around. So, he had helped them for a while, but then found any bodies, and he stopped helping them. So, they asked me if I would be willing to go to the federal prison and interview him. Help me understand him.
I said, "Sure." So, off off I went to federal prison.
I sat down beside him, and the police are sitting against the wall. I right leg touching his left leg. That's how close we were physically.
And he has this long beard, and I'm looking at him, and I'm I'm sizing him up going, "This is going to be a really interesting interview."
Cuz I could tell he's on medication.
And I said, "So, let's cut to the chase, Larry. You killed all these all these women?"
And he said, "Yes."
I said, "Why are you helping the police?" Well, he said, "They said I can go home and visit is mom." I said, "Larry, you're never going home. Ever."
You hear they lied. Police can lie.
You're not going home.
I did I poked the bear intentionally. I wanted to see what he was made of.
Oh, no, I get to go home. So, we talked about that. Eventually, I said, "Okay, Larry, let's pretend you get to go home."
"How did you kill these people?" He said, "Well, I was a Civil War reenactor."
And he gets his mutton chops. And he says, "I wore a Confederate uniform, and I would travel around the country going to these different places uh where they had these reenactments of the of the Civil War. And I would participate. In every city that he went to, those women were there, and they disappeared in every every in every case."
So, we kind of knew. Right, yeah, he he did them. You go to campus, see a woman walk up by herself, you grab her, put a knife to her throat, get her in the van, tie her up, and take her out in the woods. Eventually, he started using ether to knock her unconscious, so so he wouldn't have to struggle so much with her. Then they take her out in the woods. He said, "I always took them to the woods cuz my dad was a gravedigger, taught me how to taught me how to dig graves, and I'd take them up there. So, we So, I'd get them on the ground face down, and I'd strangle them." I said, "So, or up against a tree, I'd strangle them from behind." I said, "Larry, did you ever ever watch them die?
Did you ever look down and see their faces?" He says, "No, why would I do that?" What does that tell you? He wasn't sadistic. He had no interest in in them dying. He wasn't trying to hurt them. He was killing them, and that was important to him. I said, "Larry, my next question is very important. Do you ever have a girlfriend?" "No, never had a girlfriend." "Never had No, have you ever had sex with a girl, a woman?" "No, never." "Anybody?" "No."
I said, "Larry, have you ever had ever Have you ever had sex with a dead woman?"
He smiled at me, goes, "Well, maybe."
Of course he did. That's why he was killing them. I created this theory uh developed this theory called relational paraphilic attachment.
So, most people attach themselves to other human beings in a normal way.
We have We have attractions, we meet, we marry, we we fall in love, we have relationships.
We have short-time relationships and so on.
There are are people in our in our in all societies who don't have the skill set to do that. They're insecure, they don't know how to do it. And so, but they but we're all sexual beings and we're all going to find some way to attach ourselves [snorts] some way sexually.
And so, some people will do it with dead bodies. They don't know how to be intimate on a normal level, so they being sexually involved with with with a corpse is their level of sexuality. And we find that mainly men do that. I'd probably say 99% of necrophiles are men.
We've had a couple of women, but it's rare.
>> You were with the FBI on the Unabomber case. How did it all come about?
>> The Unabomber, he made bombs. He sometimes he delivered them uh in the United States, sometimes he mailed them.
He put a bomb on United Airlines. Some people believe it was meant to go off, some people believe it No, it just meant to scare everybody. Didn't go off, but he wanted to show people that he was in control, he could do this. And so, they started calling him the Unabomber. This went on for 15 years before I got involved. And it was 18 years before he was finally caught. So, he was around a long time. I was in Chicago, I got a phone call, I was at my hotel.
Got a phone call and and asked about the case. I was not involved with the case at all. So, I really couldn't help them cuz I stay in my own lane. I don't try to make things up. And so, I said, "I can't help you."
Afterward After I hung up the phone, I had this feeling I should write them a letter because I'd lived in a lot of the same place as Unabomber. And I kind of I've been following the case a little bit in my head, but I really wasn't involved. So, I created a profile.
Anybody can create a profile.
He's a white guy and so on. But, I operationalized the profile. What's he thinking? Where Where might he be? Where might he be? What's he doing? And I kind of I thought it through critically and and then I created this four-page profile and I sent to to the to the FBI to the task force.
I said, "If this helps you, that's great. If it doesn't, toss in the garbage."
A week later, I get a phone call from the task force. They said, "Doctor, you we get hundreds of letters every week about about the Unabomber.
You seem to know more about the case than even our agents. How is that?" I said, "Well, I'm a Unabomber." Click.
>> [laughter] >> So, of course they knew I wasn't a Unabomber because they did a did a background background check on me. And I remember when when the Unabomber Ted Kaczynski had sent his manifesto to the Washington Post, immediately turned it over to the FBI, immediately turned it over to me. Within 24 hours I had it. I said, "This is a man of very low self-esteem. He lives by himself.
Never been married.
Um very insecure, very brilliant." So, we get this call that um had the manifesto and it was a meeting in San Francisco and I went to the meeting, left my vacation with my family, flew over to San Francisco. I walk in this room with all these agents and the Unabomber says that he will not bomb anybody else if we publish his manifesto.
What do you think?
And this agent says, "Well, we should publish it because it will because he won't bomb anybody else." I said, "No, wait wait wait wait wait.
I agree we should publish it but not to because he won't bomb anybody else. He will bomb somebody else. I'll guarantee you that.
We have to publish it because it'll buy us some time but he will bomb somebody else. Because if he doesn't bomb anybody else anybody else, he ceases to exist.
Right?
His bombs are his voice.
If you recall when the Oklahoma's federal building was was blown up it'd been like 6 years since we'd heard from the Unabomber.
When that when that bomb went off in in in in Oklahoma, I turned to my colleague and said, "You wait, we're going to get hit by the Unabomber right away."
A week later, a week later, he said another bomb [clears throat] went off by the Unabomber. He so wanted to be heard.
And when his brother turned him in, uh turned him in and they and they located him in Montana, they they put a sound gun about a quarter mile from his house, this little house out there, 12 12 ft by 10 ft big, and no running water, no electricity, and they listened to him make another bomb.
And then they went to him before it was just before it's ready to go, and they knocked on his door, and and he was happy. You know, he was happy to be heard finally.
And and so he could be the Unabomber.
Cuz who is he blowing up? He was jealous. He was smart. He knew he was smarter than anybody else out there he was killing. I don't think his original intent was to kill people, but it was to get people's attention and to harm people, blow up their careers, blow up their fingers, blow up their eyes. It was his way of saying, "Pay attention to me. Listen to me."
>> We spoken about Jeffrey Dahmer, we've spoken about the Unabomber. Compared to the rest of the world, why does America have so many serial killers, or at least appear to have so many serial killers?
>> We have to consider culture when we think about uh why the US has apparently so many serial killers compared to other countries. And I've done some international comparisons, and you know, there are serial killers in every country I've looked at. I've looked at maybe 35 countries.
And in Western we we see them. Um it's often not as reported in other countries. Homicides are not reported nearly as much.
Um we're much more accurate in our in our reporting. We have Hollywood.
In in Hollywood, we we glamorize violence.
Uh a lot of societies don't do that. And so that's not part of what they do. And so that that's helps us understand it.
And of course we have domestic violence, and and and we we have a lot of that, and it's and that's we we that the open with we all these movies and documentaries and stories, and so it does it it people's attention to that. And so, some guy says, "Oh, I can do that. I I can do better than that. I can do I can kill more people." That's what we have so many mass murders and attempted mass murders in the United States.
>> And I suppose in your work and your study of the darkest parts of humanity, how do you stay hopeful about the world?
And And do you feel hopeful about people in general?
>> Um yes, I'm I'm sort of an eternal optimist. Uh I I believe that Give me Give me Give me a big pile of manure, I'm going to find a pony uh somewhere. But I I do believe that there's a lot of bad things in our in our world.
Wherever you go in the in in societies, different societies, but there's a lot of good I would say that most people are good people. They're good people make poor mistakes sometimes. They they make poor decisions, but we're still decent people overall. Then there's people who are evil.
And I I think it's important that we recognize what evil is versus what is just making stupid mistakes. And I think if we would focus more on the victims, we probably make less movies.
Uh we probably see the the horror of what they've gone through, the families, the horror of what these families have gone through. Yeah, terrible things.
>> One of the prisoners I would encounter very quickly when I was at Wormwood Scrubs was a a serial murderer by the name of Dennis Nilsen. So, I learned a great deal about serial murder um from a serial killer. And the thing I learned most of all was that you could never trust anything a serial killer tells you.
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