Originally Posted by B. Carfree

I suppose you have some data showing that mandatory seat belt use laws (generally not a primary enforcement law anyway, so you have to get caught doing something else to be cited) and headlight use laws have diminished the amount of driving where they exist relative to where/when they don't/didn't exist? Of course you don't.

However, I'm still happy to compare apples to apples and mandatory helmet laws for motorists would be an interesting situation.