Given that drink driving was a common occurrence until a few years ago, I'd suggest that at least 50% of people who secured a driving license prior to 1995 has driven drunk.
Therefore, anyone who passed their driving test before 1995 is guilty, on the balance of probability, of drink driving. Jail them all.
Drink driving is ( and as far as my memory serves always was during my service) a prevalent offence and therefore would not be dealt with on a balance of probabilities.
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