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Lex Fridman Podcast

#483 – Julia Shaw: Criminal Psychology of Murder, Serial Killers, Memory & Sex

168 min episode · 2 min read
·
Julia Shaw

Episode

168 min

Read time

2 min

Topics

Relationships, Software Development, Psychology & Behavior

AI-Generated Summary

Key Takeaways

  • Dark Tetrad Assessment: Psychopathy, sadism, narcissism, and Machiavellianism exist on continuums where everyone scores somewhere. High scores across all four traits correlate with harmful behavior, but subclinical levels are normal. Understanding these as spectrums rather than binary diagnoses prevents dehumanization and enables better intervention strategies for preventing violence.
  • Murder Recidivism Data: Homicide has only 1-3% recidivism rates, making it one of the lowest-risk crimes for repeat offenses. Most murders result from escalated arguments over trivial matters, not premeditated psychopathy. This suggests criminal justice systems prioritize retribution over prevention, as high-recidivism crimes like fraud and sexual violence receive comparatively lighter sentences.
  • Deception Detection Failure: Police officers and investigators perform no better than chance at detecting lies despite high confidence in their abilities. This overconfidence leads to wrongful convictions when interrogators misread innocent suspects. Relying on intuitive lie detection rather than evidence-based methods creates systematic errors in criminal investigations and relationship dynamics.
  • Murder Fantasy Prevalence: Approximately 70% of men and over 50% of women report fantasizing about killing someone. These rehearsal thoughts serve an adaptive function, allowing people to mentally simulate consequences and reinforce decisions not to act. Fleeting violent fantasies are psychologically normal; only persistent rumination about specific targets requires professional intervention.
  • Klein Sexual Orientation Grid: This assessment tool evaluates sexuality across multiple dimensions (identity, attraction, behavior, fantasies, lifestyle) in past, present, and ideal states. Discrepancies between present and ideal states identify psychological distress points. This framework helps people understand complex feelings about sexuality beyond simple labels, particularly useful for those experiencing identity confusion.

What It Covers

Criminal psychologist Julia Shaw discusses the dark tetrad personality traits (psychopathy, sadism, narcissism, Machiavellianism), murder psychology, false memories, bisexuality research, and why evil exists on a continuum rather than as a binary label for understanding human behavior.

Key Questions Answered

  • Dark Tetrad Assessment: Psychopathy, sadism, narcissism, and Machiavellianism exist on continuums where everyone scores somewhere. High scores across all four traits correlate with harmful behavior, but subclinical levels are normal. Understanding these as spectrums rather than binary diagnoses prevents dehumanization and enables better intervention strategies for preventing violence.
  • Murder Recidivism Data: Homicide has only 1-3% recidivism rates, making it one of the lowest-risk crimes for repeat offenses. Most murders result from escalated arguments over trivial matters, not premeditated psychopathy. This suggests criminal justice systems prioritize retribution over prevention, as high-recidivism crimes like fraud and sexual violence receive comparatively lighter sentences.
  • Deception Detection Failure: Police officers and investigators perform no better than chance at detecting lies despite high confidence in their abilities. This overconfidence leads to wrongful convictions when interrogators misread innocent suspects. Relying on intuitive lie detection rather than evidence-based methods creates systematic errors in criminal investigations and relationship dynamics.
  • Murder Fantasy Prevalence: Approximately 70% of men and over 50% of women report fantasizing about killing someone. These rehearsal thoughts serve an adaptive function, allowing people to mentally simulate consequences and reinforce decisions not to act. Fleeting violent fantasies are psychologically normal; only persistent rumination about specific targets requires professional intervention.
  • Klein Sexual Orientation Grid: This assessment tool evaluates sexuality across multiple dimensions (identity, attraction, behavior, fantasies, lifestyle) in past, present, and ideal states. Discrepancies between present and ideal states identify psychological distress points. This framework helps people understand complex feelings about sexuality beyond simple labels, particularly useful for those experiencing identity confusion.

Notable Moment

Shaw reveals that her book on bisexuality became banned in a foreign country after laws changed post-publication, making it contraband. She receives messages from readers in countries where homosexuality is illegal, asking to translate and secretly distribute copies, highlighting how visibility and representation remain dangerous yet crucial in many parts of the world.

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Episode Transcript

The following is a conversation with Julia Shaw, a criminal psychologist who has written extensively on a wide variety of topics that explore human nature, including psychopathy, violent crime, psychology of evil, police interrogation, false memory manipulation, deception detection, and human sexuality. Her books include Evil, about the psychology of murder and sadism, The Memory Illusion, about false memories, Bi about bisexuality, and her new book that you should definitely go order now called Green Crime, which is a study of the dark underworld of poachers, illegal gold miners, corporate frauds, hit men, and all kinds of other environmental criminals. Julia is a brilliant and kindhearted person with whom I got the chance to have many great conversations with on and off the mic. This was an honor and a pleasure. And now a quick few second mention of each sponsor. Check them out in the description or at lextreatment.com/sponsors. It is in fact the best way to support this podcast. We got Shopify for selling stuff online, BetterHelp for mental health, LMNT for electrolytes, and AG one for my daily multivitamin. Choose Wizen, my friends. And now onto the full ad reads. I try to make them interesting, but if you skip, please still check out the sponsors. I enjoy their stuff. Maybe you will too. To get in touch with me, for whatever reason, go to let'sstreamer.com/contact. Alright. Let's go. This episode is brought to you by Shopify, a platform designed for anyone to sell anywhere with a great looking online store. Obviously, it's an incredible platform for selling stuff, but, again, I will reiterate as I do often as we did in the DHH episode, what's also incredible is the implementation of the infrastructure, how the thing is built. The legendary well documented Black Friday, I believe, in 2021, Shopify handled 30 terabytes of data every minute. 32 plus million requests per minute hit the servers. 11,000,000 MySQL queries per second were processed. And all of that mostly Ruby on Rails. The very framework, the very programming language is not supposed to scale, and it did. And it did so incredibly well, seamlessly, and still maintain the beauty underlying that, implementation. There's this write up I recently read about how they were actually able to make that happen. There's so many interesting details, including the fact that as DHH talked about that it was a modular monolith, and it was scaled horizontally in these very interesting modular ways. Again, that's probably outside of the scope of, what I'm supposed to be doing here. Just another chance to celebrate the incredible engineering behind Shopify. And all of that to help you sell stuff. You can sign up for a $1 per month trial period at shopify.com/lex. That's all lowercase. Go to shopify.com/lex to take your business to the next level today. This episode is also brought to you by BetterHelp, spelled h e l p help. They figure out what you need and match you with a licensed …

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  • Klein Sexual Orientation Grid: This assessment tool evaluates sexuality across multiple dimensions (identity, attraction, behavior, fantasies, lifestyle) in past, present, and ideal states.

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