George W. Riddell was a Pinkerton

Pinkerton National Detective Agency

The Pinkerton National Detective Agency, usually shortened to the Pinkertons, is a private U.S. security guard and detective agency established by Allan Pinkerton in 1850. Pinkerton became famous when he claimed to have foiled a plot to assassinate president-elect Abraham Lincoln, who later hired...

 labor spy

Labor spies

Labor spies are persons recruited or employed for the purpose of gathering intelligence, committing sabotage, sowing dissent, or engaging in other similar activities, typically within the context of an employer/labor organization relationship....

 who infiltrated the Western Federation of Miners

Western Federation of Miners

The Western Federation of Miners was a radical labor union that gained a reputation for militancy in the mines of the western United States and British Columbia. Its efforts to organize both hard rock miners and smelter workers brought it into sharp conflicts – and often pitched battles...

 (WFM) in Telluride, and later became president of the Eureka miners union in Utah. Riddell was forced to resign when Morris Friedman

Morris Friedman

Morris Friedman was, until 1905, the private stenographer for Pinkerton detective James McParland. Friedman came to the attention of the public when he published an exposé of anti-union actions by the private detective industry which was called The Pinkerton Labor Spy.The book focused in particular...

 published the book The Pinkerton Labor Spy

The Pinkerton Labor Spy

The Pinkerton Labor Spy is a nonfiction book published in 1907 as an exposé of intrigue and abuses by the Pinkerton Detective Agency in general, and by chief agent James McParland in particular....

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Riddell was covertly identified as agent No. 36 in the Pinkerton Agency, which charged $7,000 to the Telluride Mine Owners' Association

Mine Owners' Association

In the United States a Mine Owners' Association, also sometimes referred to as a Mine Operators' Association or a Mine Owners' Protective Association, is the combination of individual mining companies, or groups of mining companies, into an association, established for the purpose of promoting the...

 for his services over a period of two years. He was tasked with discovering an "Inner Circle" of conspirators in the WFM union, but he found no trace of any such group. The Inner Circle theory had been promoted by James McParland

James McParland

James McParland,There are various spellings of James McParland's name. His stenographer, Morris Friedman, wrote a book about him — as "McParland." The Pinkerton Labor Spy, New York, Wilshire Book Co., 1907). also known as James McParlan,The Corpse On Boomerang Road, Telluride's War On Labor...

, the head of Pinkerton's Denver division. Alleged evidence for the existence of a group of conspirators were the actual murder of Arthur L. Collins

Arthur L. Collins

Arthur Lancelot Collins was an English-born mine manager in the American state of Colorado. He was born July 8, 1868, in Truro, England. He was the son of a prominent mining expert, Joseph Henry Collins. The Collins family ran a business, J.H. Collins & Sons, Mining and Metallurgical Engineers....

, and the alleged murder of mine guard William J. Barney

William J. Barney

William Julius Barney was born to William Miles Barney and Millison J. "Melissa" Rannells, on August 14, 1867. William J. may have led a normal life, conducting normal business and living as a member of a normal family, but for one act: he quit a job as a Telluride, Colorado mine guard during a...

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