Good to know.
They just looking at tailpipes that drive by, or do they pull you over at random just to look under the hood?
I've heard that some areas have machines that measure your exhaust as you drive by, but that seems like an expensive proposition to make mobile, so likely makes a random inspection a little more likely.
Wonder if they're looking for "tuned" diesel trucks belching soot, or missing catalytic converters and such like that.
paul