Secrets to Your Success: Mary Ellen O'Toole

"Empathy is such a critical trait, even if you're sitting across the table and somebody has said to you, 'Yes, I've murdered 48 people,' and I've had that happen," explains Mary Ellen O'Toole, a psychologist and FBI profiler.

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At a very young age, she wondered what people thought about when they murdered other people. Mary Ellen says, even though these thoughts scared her mom, she was fascinated with people who do violent things.

Mary Ellen studied psychology in college and went on to get her PhD. She worked briefly as a therapist, but felt drawn to a career in law enforcement. She says it must have been in her genes to choose that path. Her father was an FBI agent, her mother worked for the FBI, and her brother was a San Francisco police officer.

She began her law enforcement career with the San Francisco DA's office as a criminal investigator, and in 1981, Mary Ellen became an FBI agent assigned to bank robberies and violent crimes. She says a lot of the agents didn't want to do the interviews with especially violent offenders, but she would raise her hand and volunteer.

As an FBI profiler working on high-profile cases, she helped identify Unabomber Ted Kaczynski in the 1990s, and she interviewed serial killer Gary Ridgway, who killed 49 women in the 1980s and 90s. Mary Ellen says she was surprised with Ridgway's average appearance, pleasantness, and sense of humor. "What was the most chilling was he was so matter of fact about what he said he did," she explains. "Here was a man that lived in society, maintained a job and a relationship, had his own son, and yet he was the most prolific serial sexual killer the United States has ever seen."

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Cases like Gary Ridgway were the inspiration for Mary Ellen's book, "Dangerous Instincts: How Gut Feelings Betray Us." She says the book is about how to read people more effectively. "You know not to get on an elevator if somebody in there looks like Charles Manson," she explains, "but it's the people that kind of subtly come into your life or your children's life. They are charming. They are outgoing, and you're thinking, 'Gosh, you're the greatest thing' until you're not."

Four years into retirement, Mary Ellen is still busy teaching at the FBI Academy, consulting on cases, and writing. The perk? These days, she can write in her pajamas. Mary Ellen says she's still motivated and fascinated by what makes people tick. "I can't get enough of it," she says.

For those aspiring for success, Mary Ellen advises to find positive people to give you realistic feedback. She says, "Don't depend on negative people to predict what the rest of your life will be."

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