Hedgepeth was born in Prairie Home, Missouri on April 14, 1856. He ran away from home at age 15, worked as a cowboy, and was an outlaw by the time he was 20, having killed in Colorado and Wyoming, as well as having robbed trains.
Appearance and reputation
In a 1996 American Cowboy article titled "The Debonair Killer", David P. Grady noted: "Marion Hedgepeth looked like a dude, but 'dangerous' and 'deadly' fit him better". The dark-complexioned, wavy-haired six footer, who roamed from town to town as a hired gun, Grady wrote, maintained the fastidious, gentlemanly appearance of a dandy, sporting a bowler hat and diamond stickpin. WANTED posters noted that his shoes were usually polished.
An article published in the Express Gazette, Volume 20 by "a man from Missouri", who described himself as "a disinterested student of train robbing", indicated that appearances were strategically important to Marion and his crew. In preparation for the Glendale robbery, he noted, Hedgepeth, "his three pals" and his wife "assembled in that city and rented a house in a fashionable quarter of the town. They furnished the house well, and during the two or three weeks prior to the holdup, each robber purchased for himself swell attire piece by piece, so as not to attract attention."
Despite his swell appearance, however, Hedgepeth "was a deadly killer and one of the fastest guns in the Wild, Wild West". Allan Pinkerton, whose National Detective Agency had sought to capture Hedgepeth and his gang for years, noted that Marion Hedgepeth once gunned down another outlaw who had already unholstered his pistol before Hedgepeth had drawn his revolver.
In November, 1883, Hedgepeth was sentenced to serve a term of seven years in the Missouri State Penitentiary in Jefferson City, Missouri, on the charge of larceny and jail breaking. He was discharged on February 16, 1889.
Hedgepeth lived for a while in a lawless region of Kansas City, Missouri, known as "Seldom Seen" because the police were seldom seen there. He became a member of the "famous Slye-Wilson gang of safe blowers and highwaymen".
On November 30, 1891 Hedgepeth and the other members of Slye-Wilson gang (Adelbert Denton "Bertie" Slye, James "Illinois Jimmy" Francis and Lucius "Dink" Wilson) - which by 1890 newspapers referred to as the "Hedgepeth Four" - robbed a train of $40,000 in Glendale, Missouri near St. Louis, Missouri personally escaping with some $10,000. The gang fled to Salt Lake City and disbanded. After being relentlessly pursued by the Pinkertons, he was finally arrested on February 10, 1892 in San Francisco, along with Slye, and brought back to Missouri for trial. Convicted, he was sentenced in 1893 to 25 years in the Missouri State Penitentiary. Hedgepeth informed on a former cell-mate, whom he knew as "H.M. Howard" but was really H. H. Holmes, which eventually resulted in the notorious killer's unmasking, conviction and execution in 1896. For this Hedgepeth was pardoned by Missouri state governor Joseph W. Folk 14 years into his 25-year term. He was released sick with tuberculosis and "looked like a skeleton and appeared 60 years old."
He was arrested in 1907 in Omaha, for the burglary of a storage house at Council Bluffs, Iowa. He was convicted and sent to the Iowa State Penitentiary in Fort Madison, Iowa  in March, 1908, and was released after serving one year.
- Adelbert Slye was arrested in Los Angeles California
- James Francis killed a Ft Scott policeman S.B. McLemore January 23, 1892 and was killed in Pleasanton Kansas 
- Lucius Wilson was involved in the killing of NY Syracuse Detective James A Harvey August 1, 1893  and was arrested; he was executed May 14, 1894
Hedgepeth was shot and killed by police officer Edward Jaburek, on December 31, 1909 during a botched Chicago saloon robbery at 18th and Avers Avenue. He died at St. Anthony's Hospital and was buried in the Cook County Cemetery on the grounds of the Cook County Poor Farm at Dunning.
- Grady, David P. (July–August 1996). "The Debonair Killer". American Cowboy: 64–65. Retrieved 3 January 2013.
- Her Sacque of Sealskin: A Chapter of Western Bandit History. 20. Express Gazette. p. 64. Retrieved 28 June 2012.
- "Missouri Bandit Shot By Officer", Springfield(Mo.) Daily Republican, January 4, 1910. Retrieved October 14, 2014
- "HEDGEPETH DIED A ROBBER. The End of the Missouri Bandit in a Chicago Saloon Holdup." Kansas City Times, January 4, 1910
- "The Board of Crimes". The Weekly Gleaner. 14 (27). 3 March 1892.
- Schechter, Harold. Depraved: The Definitive True Story of H.H. Holmes. books.google.com. p. 89.
- William B. Secrest. Dark and Tangled Threads of Crime: San Francisco's Famous Police Detective. p. 241.
- The North American Review
- ODMP memorial for S.B.McLemore
- State Republican Feb 11, 1892
- ODMP memorial for James A Harvey
- North American Review
- ODMp memorial
- list of Wild West outlaws