Chief Shellbury (first name unrevealed) was the commander of the U.S. Coast Guard Patrol Boat 619, which was stationed in Dick Tracy's city. Shellbury was an avuncular man with a narrow face and pronounced teeth. Shellbury was spoken highly of by his superior officer Captain Smith, who mentioned that Shellbury had been a "rum runner" during Prohibition and had a reputation as a man of action. Shellbury had encountered human traffickers previously during his career in the Coast Guard and was familiar with their methods.