If you use one and you're in the driving seat it means (1) you've been drinking and (2) you're thinking of driving. I'm sorry but if you're in that position you should NOT be drinking. There are no two ways about it. I get very uptight about drink and especially about drinking and driving and think this is just another ploy of parting people from their cash and can give a false sense of security.
Nicola Sturgeon’s husband re-arrested