Allan Pinkerton (1819–1884)
Allan Pinkerton founded the Pinkerton National Detective Agency in 1850 and is often viewed as a founder of modern private investigation. Born in Glasgow, he immigrated to the United States in 1842 and moved from cooper work into investigative and law-enforcement work.
His agency became known for major assignments, including protecting Abraham Lincoln before his inauguration, Union intelligence work during the Civil War, and pursuit of notorious outlaw groups. Pinkerton also advanced practices such as centralized criminal files, undercover operations, and broader use of photographic identification.
Kate Warne (1833–1868)
Kate Warne became the first female private detective in the United States when Pinkerton hired her in 1856. She argued that women could gather intelligence in settings men often could not access.
She played a key role in exposing the 1861 Baltimore plot against Abraham Lincoln and later led Pinkerton's female detective unit. Her undercover work helped open opportunities for women across the profession.
William J. Burns (1861–1932)
William J. Burns founded the William J. Burns International Detective Agency in 1909, which grew into one of the country's largest private agencies.
He later served as Director of the Bureau of Investigation (the FBI's predecessor) from 1921 to 1924. His career helped bridge private investigation and federal investigative standards.
Jay J. Armes (1932–Present)
Jay J. Armes became a widely known private investigator in the 20th century despite losing both hands in a childhood accident. Based in El Paso, he handled high-visibility matters including kidnapping recovery, security work, and complex fraud cases.
His career underscored how strategy and persistence can outweigh physical limitations. His public profile even led to a toy action figure modeled after him.
The Legacy Continues
These investigators helped shape the methods, ethics, and public expectations of private investigative work.
Modern agencies build on that foundation by combining traditional fieldcraft with current technology and legal standards.