Will Self presents a very British solution to the issues surrounding the legalisation of marijuana.

Considering the pervasiveness of cannabis in the UK, he says the question that should currently be preoccupying us as a society is not whether marijuana should be legalised, but how.

"My model here would be the old Tote," he says, "a form of nationalised gambling that for many years mitigated its worst effects by limiting opportunities and hence possible losses."

He says that we must avoid the "commercialised free-for-all that's emerging in the US and parts of Canada."

Producer: Adele Armstrong