...or at least have le bag in the car.
Starting today, the nanny state of France requires you to have an approved Breathalyzer device in your car when driving there. Actually, they're recommending that you buy two, just in case you might use one -- and do not try to suss the logic of that or your head could explode.
Here's the link with all you need to know from the Breathalyzer industry, which no doubt is busy, busy, busy lobbying to try to have lucrative laws like that one passed elsewhere.
Not here in the U.S., you say? Well, not bloody likely, I agree. On the other hand, Americans in a lot of states do kind of passively accept those disgraceful traffic red-light and speed cameras, and the road to le bag is a slippery slope.