And again, "Mens Rea" does not apply to Liability Crimes. That is to say, the bar gets busted because Jr. got busted on a DUI or fatality. The bar's insurance company feels that the bar is too high a risk, and refuses to insure the bar. Thus, the bar will close. In other cases, I have seen bars get routinely busted for underage drinking, and the City refuses to issue them a liquor license. In the city I went to college in, the bar owner made the business decision that it was cheaper to pay the fines than to turn away underage drinkers. Stupid decision on his part.
You should live around here! Not only do they want to hang you if you get fooled by a fake ID,but the cops and some citizen's groups regularly send in underage kids to these places to try and buy! And that's for booze AND CIGARETTES!!!!!(sometimes lottery tickets!)
But if the store or bar catches a kid with a phony ID,the cops usually let them go with a warning or a deal is made with the judge that if Junior behaves for 6 months or so,it'll all be forgotten!