The "wild west" found its way into the Bitterroot Valley on January 26, 1864 with the hanging of Whiskey Bill (Bill Graves) on or very near current Refuge properties. An interpretive sign (jpeg to left) was in place on the Refuge in the 1970's "marking" the spot of the hanging. What follows are quoted accounts from that time by Thomas Josiah Dimsdale from his book Vigilantes of Montana.
"Another powerful incentive to wrong-doing is the absolute nulity of the civil law in such cases. No matter what may be the proof, if the criminal is well liked in the community 'Not Guilty' is almost certain to be the verdict, despite the efforts of the judge and prosecutor" (Thomas Josiah Dimsdale, preface [p. 14 & 15] of Vigilantes of Montana, Princeton University, 1905)
"A company of three, headed by the “old man,” (likely Captain Williams) started off to Fort Owen, in the Bitter Root Valley, in pursuit of Whiskey Bill (Bill Graves, the coach robber). This worthy was armed and on the look-out for his captors; but, it seems, he had become partially snow-blind by long gazing. At all events, he did not see the party with sufficient distinctness to ascertain who they were, until the “old man” jumped from his horse and covered him with his revolver. He gave up, though he had repeatedly sworn that he would shoot any Vigilanter who would come his way. His guilt was notorious throughout all the country, and his capture was merely a preliminary to his execution. The men took him away from the Fort in deference to the prejudices of the Indians, who would have felt no desire to live near where a man had been hanged. Graves made no confession. He was what is called in the mountains a “bull head,” and was a sulky, dangerous savage. Being tied up to a limb, the difficulty was to make a “drop,” but the ingenuity of the leader was equal to the emergency. One of the men mounted his horse; Graves was lifted up behind him, and, all being ready, “Good-by, Bill,” said the front horseman, driving his huge rowels into the horse's flanks as he spoke. The animal made a plunging bound of twelve feet, and Bill Graves, swept from his seat by the fatal noose and lariat, swung lifeless. His neck was broken by the shock" (page 172-73, Vigilantes of Montana by Thomas Josiah Dimsdale [1905, Princeton University], public domain and now digitized by Google at http://google.com/books?id=X4k-AAAAYAAJ)