Mailbox editorial cartoon, Safety First, 1924. Courtesy of the Ron J. Pry Historical Collection

Among those who learned that robbing the U.S. mail leads to trouble was William Patrick Colbeck. Through the mid 1920s, Colbeck was part of an organized crime operation in Illinois, focusing on smuggling liquor during prohibition.

Although suspected of committing murders and several other robberies, it was the mail robbery that brought Colbeck to justice. Colbeck went after mining company payroll cash that was being moved by mail. In November 1924 he and five associates were convicted of mail robbery and sentenced to fifteen years in prison. This cartoon, published in the St. Louis Star, notes that criminals would do well to avoid trying to attack the U.S. mail.