John Marion Thomas was born March 31, 1884, at York, Nebraska. Prior to his employment with the Constabulary, he served 30 years with the U.S. Cavalry and U.S. Marine Corps. He was honorably discharged on January 31, 1927, with the distinguished rank of Sergeant Major. At the time of his employment on March 12, 1927, he resided at Drumright, Oklahoma. He was 5' 7½ " tall and 43 years old. He was employed as a civilian inspector and instructor of small arms at the Constabulary Training School but was soon given enlisted status with the rank of Sergeant.
On May 8, 1927, Sergeant Thomas was a passenger in a patrol vehicle driven by Captain Albert Carlson. The vehicle became involved in a three-car collision on Ridge Pike, just west of Jeffersonville, Montgomery County. Sergeant Thomas was thrown from the vehicle and suffered extensive injuries. He died before reaching Norristown Hospital. Carlson was injured but recovered.
Sergeant Thomas is buried in Drumright, Oklahoma. He was survived by his brother, Mr. H. E. Thomas, of Drumright, Oklahoma. Sergeant Thomas had completed less than two months of Constabulary service.