In 2005 the Government asked the Advisory Council on the Misuse of Drugs to carry out a review of the classification of cannabis which took into account the harms from cannabis use on both physical and mental health, and the levels of cannabis use following reclassification. The evidence it reviewed is set out in Annex 4 of its Report, Further consideration of the classification of cannabis under the Misuse of Drugs Act 1971, together with prevalence data extracted from the British Crime Survey.