Patrol Inspector Earl A. Roberts was shot by a liquor smuggler at about 8:00 p.m. Saturday, March 23, 1929, and died from the wound at 5:00 p.m., Sunday, March 24, 1929. The shooting occurred on the St. Clair River, in Algonac, Michigan. Inspector Roberts was working with Patrol Inspector Stanley H. Graham, when they noticed a motorboat towing a small rowboat approaching from the direction of Canada. The officers proceeded along the shore following the course of the boat in an attempt to intercept the boat when the shore was reached. The officers separated in order to converge on a probable landing point. The motorboat came to the shore at which time Patrol Inspector Roberts stepped aboard the stern of the boat and identified himself as a federal officer.
Patrol Inspector Graham, who was standing on the shore a few feet from the boat, flashed his light on the occupants and observed that an individual known to him as Vet Brown was standing in the center of the boat with a .45 caliber revolver aimed at Inspector Roberts. Inspector Graham instructed Brown to surrender; however, the latter fired, point-blank, at Inspector Roberts and immediately whirled toward Inspector Graham, firing the remaining bullets in that direction. Inspector Graham emptied his gun in returning the fire but none of the shots exchanged hit their mark. A second individual in the boat, later identified as Clayton Smith, had jumped from the boat into the rowboat that was being towed and had cast-off, setting a course for Canada. Smith was a witness to the events and later testified on behalf of the government in the case against Brown.