Drunken cycling is an offence and a very bad idea. But is it much of a road safety problem? Police enforce some traffic laws, but seldom drunk cycling. CTC examined data for 5 years to see how many fatalities involve alcohol and cycling in this country.
For some months I've had an irregular correspondence with a Polish cycle campaigner who relates that the police treat drunk cycling under the same laws as they treat drunk driving.
In Poland - as with most of the rest of Europe - the legal blood alcohol limit is far lower than in the UK: you can be fined at over 20 mg/100ml of blood and jailed at 50. In the UK the limit is still 80, despite a recent report recommending reduction to 50.