SIR - Michael Gove was recently mocked for saying that he did not trust the opinions of experts. His point is well made by a recent report from the Institute of Economic Affairs which suggests that by legalising the use of cannabis, the Exchequer would benefit by around £1 billion a year.

Now I have dabbled in the importation of illegal drugs since being posted to the Customs Parcel Post Depot in Dover in 1958 and legal mind altering substances like beer, wine, spirits and tobacco as well. The difference is that cannabis has been a prohibited substance since 1928 whereas the others have been allowed and taxed since Roman times.

The IEA says a legal market would drive the smugglers out of business allowing a revenue duty and VAT to be applied just like any other commodity. Just why they think the drug barons being hardened criminals would roll over and quit the field on the governments say-so is not explained. Nor do they explain why approved distribution centres would be popular when for most 'recreational users' half the fun of smoking pot is the shiver of guilt which comes knowing it is illegal.

Brian Holmans, Langley Road, Bingley