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Security History: Detective Kate Warne

​In this new series from Security Management, we will examine historical events and people throughout the year that influenced the development of the security profession.

On 22 August 1856, private detective Allan Pinkerton met a young woman standing at the door of his Chicago office. She introduced herself as Mrs. Kate Warne and told Pinkerton that she was in search of a job—not as a secretary, but as a detective. 

Pinkerton was taken aback—a female detective was unheard of in 1856. American police departments would not begin hiring female officers until the Los Angeles Police Department hired Alice Stebbins Wells in 1910. And those female sworn officers had limited roles; they often were not entitled to carry a gun and were typically tasked with upholding laws protecting women and children. Nevertheless, traditional roles did not hold Warne back; she told Pinkerton that a woman could collect information that a man could not, could persuade people to reveal secrets, could collect gossip and overhear news in social functions, and could pose as a wife on assignments where a couple would elicit less suspicion. 

Pinkerton thought about it that evening a great deal. But he recognized opportunities and pursued them. The next morning, he hired Kate Warne as the Pinkertons’ first female detective.

Warne served with the Pinkerton Agency for 12 years. She participated in numerous investigations and she taught and supervised other female operatives. She became superintendent of the Female Detective Bureau.

One of her notable cases was the 1861 Baltimore Plot to assassinate U.S. President-elect Abraham Lincoln. She not only helped uncover the plot by going undercover at secessionist parties in Baltimore, but she posed as Lincoln’s sister with the future president disguised as an invalid during a covert train ride to Washington, D.C.

After the Civil War, Warne investigated the murder of a bank-teller. By befriending the suspected murderer’s wife, Warne was able to discover where the man had hidden the $130,000 he stole in the course of the crime.

Warne served as Pinkerton’s “right hand” and upon her death in 1868, she was buried on the Pinkerton family plot alongside several other Pinkerton agents. Pinkerton specifically thanked Warne in his memoirs.

To any future female prospective agent, Pinkerton reportedly said: “In my service you will serve your country better than on the field. I have several female operatives. If you agree to come aboard, you will go in training with the head of my female detective, Kate Warne. She has never let me down.” 

Learn more about some of the groundbreaking female detectives in The Pinks; a book review is available here​​.


Chris Hertig, CPP,CPOI (Certified Protection Officer Instructor), is a member of the York History Writers Roundtable. He is on the Professional Development Council and the board of directors for the International Foundation for Protection Officers (IFPO).