William J. Sheehan

Picture of Special Agent William John Sheehan
Date of Birth: 
Date of Death: 
June 2, 1955
Location of Death: 
Milwaukee, WI
Picture of US Treasury, IRS Investigator badge - Alcohol and Tobacco Tax Division

Circumstances of Death

Special Agent William John Sheehan was traveling from Chicago to Milwaukee in his government vehicle on official business. When he did not arrive in Milwaukee as scheduled, a massive search was undertaken by agents and local police. Three days later, Agent Sheehan was found dead inside his vehicle in South Milwaukee, Wisconsin. His death was attributed to a pulmonary embolism.


Agent Sheehan joined the Alcohol Tax Unit (ATU) on July 1, 1936, and was assigned to the Chicago Field Division. During his career, Agent Sheehan gained significant prominence as a handwriting and fingerprint expert. Later, he was appointed as the agent in charge of the Chicago fingerprint section. He worked on many locally famous cases of the day, including several major narcotic cases, in which he matched latent fingerprints from envelopes and containers with prominent suspects. This was a relatively new law enforcement technique at the time.

One of his most famous handwriting cases involved the case of Eugene Sullivan, who was falsely accused and convicted of robbing the Northern Indiana Public Service Company. Mr. Sullivan spent nine years in jail before the investigation by Judge William Murray and the examination by Agent Sheehan proved that he was innocent. As a result, Mr. Sullivan was released from prison.

During his career, Agent Sheehan received numerous letters of commendation and appreciation from other law enforcement agencies for his professionalism and expertise. Agent Sheehan received his LLB from San Francisco Law College (1923) and worked for several different government agencies before joining ATU.


Agent Sheehan was born in San Francisco, California. He was single and survived by two sisters, Mary Sheehan and Catherine MacLachlan.

Last Reviewed June 26, 2020