He led the 1901 strike in that mining camp to a successful conclusion, gaining a standard minimum wage for the miners.

He was shadowed by Pinkertons hired by the Mine Operators' Association, stalked by gunmen, had a price on his head, was arrested and charged with crimes he never committed, and was condemned by the anti-labor press as a "murderer.

"[citation needed] Bulkeley Wells, a Telluride mining company president and manager who was "born to privilege... [and was] convinced laborers were beneath him," was intent upon hanging St. John.

Wells conspired with others, including Pinkerton manager James McParland, to accuse the head of the WFM local of conducting a "reign of terror" — and in particular, of murdering William J. Barney, a mine guard who had left his post.

In January 1915 he retired to a small copper claim in New Mexico, but was later arrested for a May 1918 mass trial as the federal government brought sweeping indictments against 101 IWW members.