Daniel A. Gilbert

Daniel A. Gilbert (August 31, 1889 – July 31, 1970) was an American police officer and politician who was active in Cook County, Illinois's law enforcement from 1917 to 1950, and referred to as the world's richest police officer due to his net worth of $360,000. He unsuccessfully ran for Cook County Sheriff with the Democratic nomination in 1950.

Entering the workforce at age 11, Gilbert was elected secretary-treasurer for his local affiliate of the Baggage and Parcel Delivery Drivers Union and later controlled multiple Teamsters locals. He became a police officer for the Chicago Police Department in 1917, and rose to captain by 1926. State's Attorney Thomas J. Courtney selected him to serve as chief investigator in 1932, and Gilbert held the position, with a brief interruption in 1935, until his resignation in 1950.

Jacob Arvey had the Democratic nomination for sheriff given to Gilbert in 1950, despite opposition from U.S. Senators Scott W. Lucas and Paul Douglas. Gilbert's testimony before the Kefauver Committee was leaked and Gilbert's defeat was blamed for other Democratic losses on the ballot, including that of Lucas.