/>The medical manufacturing is so high that the UK is the highest exporter of cannabis in the world. The suggestion from the IEA is that if cannabis is legalised, the responsibility rate should not be too excessive, as high tax would make retail costs less aggressive and could prevent significant shrinkage of the black market. The report concluded that the present UK cannabis black market is worth over £2.5bn and cannabis tax yields could be between £204 million and £571 million. In June 2010, it was revealed that the house Office had been avoiding complying with the FOI request "to avoid a concentrate on the gaps in the evidence base" that its present drug policy ha