A little off topic, but interesting:
Recently we traveled in South America, and when passing through several of their many "passport control" stations in airports, I could see what showed up on the officer's screen after he scanned my passport.
It appeared he had a pop-up with about 5 categories, like "criminal", or "customs", etc. Each one had to turn to "Negativo" as the computer did its thing, and once they all did, it turned green and he then passed my document back to me.
I expect that Canadian and US border folks have a similar or even more detailed screen in front of them. (And I suspect the Peruvians will be mad that I peeked at their screens!)