Credit: Library of Congress
The Pinkerton Detective Agency was first used in Pennsylvania by Franklin Gowen, President of the Reading Railroad, who hired them in the early 1870s to infiltrate the Molly Maguires and crush organizing efforts by Irish miners in northeastern Pennsylvania. After Henry Frick's disastrous attempt to employ a private army of Pinkertons at the Homestead Steel Works led to a pitched battle and 12 deaths in 1892, the Pennsylvania legislature passed a law outlawing the importation of armed guards from other states.
