[khuey]

The CPR was done by 1885. Alberta and Saskatchewan weren't provinces until 1905. The original transcontinental railroad in the US was finished in 1869. Utah didn't become a state until 1896.

These places were very much the frontier when the railroads were built. There was minimal law enforcement provided by the barely-existent territorial governments and the railroads responded by hiring private security (famously Union Pacific hired Pinkerton) and building their own private law enforcement capacity and this was eventually formalized by laws in both countries permitting the practice of railroads having private police.

Much less familiar with the relevant Mexican history.