Enter the splendid 1953 action epic, Fort Vengeance, starring the rugged James Craig, with Keith Larsen, Reginald Denny, and the oddly-cast-but-lovely Rita Moreno. Craig and Larsen play brothers Dick and Carey Ross, with Craig as the elder (and wiser) of the two. As the picture starts out, they're on the run from a posse, headed for the Canadian border. Larsen's character, Carey, has shot a man in what is ostensibly self-defense, and it's up to the older to get him out of the jam. They do out-distance the sheriff and his men, and they manage to make it to the jurisdictional safety of Canada's lush south. Immediately Carey's impulsive recklessness comes to play, as he shoots one of a pair Indians on the trail...an act which will come back to haunt the brothers.
Stuck north of the border and lacking work, Dick decides that he's going to join up with the Northwest Mounted Police, and little brother tags along. Things move quickly from there; Dick dives fully into his new life, taking on his responsibilities with vigour, while Carey chafes at these new restrictions and begins to engage in behaviours that will cause trouble for everyone around him.
Then there is a murder.
The director, Lesley Selander, really did a solid job here. He was a juggernaut of western film direction, cranking out dozens of wonderful cowboy movies from the mid-30's into the 1960's, in which he also directed for television, including Laramie, The Tall Man, and even Lassie! Fort Vengeance goes to the top of my list of his films, with a childhood fave of mine, Quincannon, Frontier Scout (available HERE).
This great example of Mounted Police perfection is a Warner Archive release HERE...get it while you can!
Here's my list of Mountie films! Please feel free to download, and let me know any that I might be missing!