Sept 15, 1920, Winnipeg Tribune
So here's a Portage and Main idea from back in 1920.
Apparently cities like Detroit used these traffic signal crow's nests, complete with signals and a traffic officer, in some of their larger intersections. Chief Newton saw them and decided they would be a good idea for this city, first at Portage and Main, then, perhaps, at others.
Despite the police department's recommendation and the headline above the image, I could find no evidence in subsequent newspapers that this was ever erected at Portage and Main. I am sure that the officers whose duty it might have been to staff the structure breathed a sigh of relief !