I live in Australia and work in the hospo industry. Down here, it is a legal requirement for all bars to pour a standard 30ml spirit. We mostly use EMU's, although jiggers are still basically allowed.
I read oftentimes on restaurant and bar social media about customers complaining about weak standard drinks, or giving cudo's to bars that pour strong drinks.
So my question is: does the US have a regulated, legal standard pour for spirits and if so, is it not policed?