I say legalise cannabis,since it undoubtedly helps many sufferers of painful degenerative conditions.However,I would caution users that they would be in line for very serious penalties if caught driving cars,buses ,trains and trucks,or flying aeroplanes,whilst under its influence.Under those circumstances,there would have to be a non-negotiable and lengthy custodial sentence, say 5 years minimum.
    As to crack,crystal meth,heroin,cocaine,et al, I would make it a 20 year prison stretch for anyone in possession of,or selling,such drugs within 30 miles of any school.Since we are a small island with many schools,this would force most dealers and/or users to become concentrated in areas like Dartmoor for their pathetic activities ( preferably in the rain)
          And,of course,nobody who tests positive for "hard" drugs would get free medical treatment------that is NOT what our National Health Service is for.
               Opium is the religion of the people...( Sadly).