McParland had Western Federation of Miners leaders Bill Haywood, Charles Moyer, and George Pettibone arrested in Colorado. In his book "Roughneck", writer Peter Carlson wrote that the extradition papers falsely claimed that the three men had been present at Steunenberg's murder. Carlson described the arrest across state lines as a "kidnapping scheme." However, under Idaho law, conspirators were considered to be present at the scene of the crime. The extradition was done with the cooperation and involvement of the Colorado authorities, and was later upheld by the US Supreme Court, with one dissent.