Episode 075: Mary Ellen O’Toole – Serial Killers, Sexual Sadists

Retired agent and former FBI profiler Dr. Mary Ellen O’Toole, Ph.D., served in the FBI for nearly 28 years. For more than half of that time, she worked in the Bureau’s prestigious Behavioral Analysis Unit (BAU) where she consulted on many of the FBI’s highest profile and most complex cases, including homicides, kidnappings, sexual assaults, predatory behavior, child molestation and other crimes of violence. In this episode of FBI Retired Case File Review, Mary Ellen O’Toole, who is recognized as the FBI’s leading expert in “psychopathy,” discusses serial killers and reviews the case of the Green River Killer Gary Ridgway, who was convicted of killing 49 women. Post retirement, Dr. O’Toole is an internationally recognized Forensic Behavioral Consultant and Lecturer. She makes frequent media appearances on major TV news programs and radio affiliates and has been interviewed in prominent newspapers and publications around the country. In 2015, Mary Ellen O’Toole was appointed as the Director of the Forensic Science Program at George Mason University in Fairfax, Virginia. Her book Dangerous Instincts: How Gut Feelings Betray Us introduces the right way to assess people for everyday situations in our personal and professional lives, and how to make safer decisions about them and the situations they create for us. You can learn more about Dr. Mary Ellen O’Toole by visiting her website MaryEllenOtoole.com.

Supervisory Special Agent (Retired)

Mary Ellen O’Toole

4/ 5/1981 – 1/7/2009

Dr. Mary Ellen O'Toole. Ph.D.









Serial Murder and Serial Killers

The FBI website features an eight part series on serial murder and profiles several well-known serial killers:

Serial Killers – Part 1: The FBI’s Role Takes Shape

Mary Ellen O’Toole’s website features a fascinating blog post titled Top 10 Reasons Not to Go With Your Gut. It should be a “must read” for those who go with their gut when making decisions.

May Ellen O’Toole’s fascinating book on the truth about gut feelings can be purchased here.












Jerri Williams

View posts by Jerri Williams
Jerri Williams, a retired FBI agent, author and podcaster, jokes that she writes about the FBI to relive her glory days. After 26 years with the Bureau specializing in major economic fraud and corruption investigations, she calls on her professional encounters with scams and schemers to write police procedurals inspired by true crime FBI cases in her Philadelphia FBI Corruption Squad crime fiction series featuring flawed female FBI agent Kari Wheeler. Jerri’s FBI for Armchair Detectives nonfiction series enables readers to discover who the FBI is and what the FBI does by debunking misconceptions about the FBI in books, TV, and movies. Her books are available as ebooks, paperbacks, and audiobooks wherever books are sold. She’s also the host of FBI Retired Case File Review, a true crime podcast with more than 250 episodes available for free on all popular podcast apps.


  1. BarbaraAugust 18, 2017

    Absolutely fascinating! And somewhat life-changing. Take home message for me: (without becoming overly suspicious) it is prudent to be cautious with those new in your life.

    I have always told people that I am hopeless at figuring out what someone is like at first meeting. Happy to know that’s normal, and advisable.

    1. Jerri WilliamsAugust 19, 2017

      I had always believed that our gut feelings would warn us and help keep us safe. Now I understand that’s not necessarily true. I agree with you, listening to the interview with Mary Ellen could prove to be life-changing. Thanks for listening!


Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Scroll to top
Malcare WordPress Security