Visible crew/equipment: In the scene where the judge is releasing Clint Eastwood and telling him that his story checks out he calls him over to the window to watch a hanging. As the guards walk down the scaffold steps on the ground under the gallows there is a pile of rope and next to the rope is a modern electrical box of some type. It's silver with with louvers (vents) in it.
Factual error: In the scene where people are arriving in town for the hanging, a family are told they have tents set up in the Boondocks. "Boondocks" is a Philippino word that entered the English language when the Philippines was a colony of the U.S. The movie is set 9 years before the Spanish American war so the word didn't exist in the English Language during the period of the movie. (01:11:20)von
Plot hole: The judge asks Jed Cooper if he would like to see what McCloud looks like, (McCloud is the killer who cheated him and murdered the rancher), as he is being hanged. Of course since Jed Cooper had previously purchased the cattle from McCloud, he knew what he looked like. (00:10:00 - 00:15:00)
Continuity mistake: When the blacksmith looks up and recognises Jed, he is standing in front of the fire ready to put the horseshoe in. After Jed dismounts and the camera cuts back, the blacksmith is standing a few feet to the right of the fire.
Factual error: When the camera pans above the gallows prior to the hanging, modern high tension electrical lines are visible through the trees in the far background.