Although the name of the territory in which this episode takes place is never mentioned, Colorado was the only state admitted to the union during Grant's presidency, with the proclamation being signed on 2 August 1876. The next states to be admitted were North and South Dakota, on 2 November 1889, twelve years after Grant left office (and four years after his death). It's unlikely that politicians in Dakota Territory would be anticipating statehood that far in advance. The last territorial governor of Colorado was John Long Routt, appointed by President Grant on 29 March 1875; he also served as the first state governor until 14 January 1879.
Jim West's trial is conducted on the slightly redressed set of Cimarron Strip (1967), which set was also borrowed for several other episodes.