Cannabis: a history by Martin Booth

In the Nineties, William Foster was tried in America for possessing ten cannabis plants and some cuttings. Medical evidence proving that marijuana was an effective treatment for his crippling rheumatoid arthritis was ignored, and Foster was sentenced to 93 years in jail. Since then, it has emerged that Mo Mowlam, Bill Clinton, Al Gore and even Prince Harry have all had a toke on the weed. It is estimated that 30 million Americans regularly get stoned, and the drug is treated as a religious sacrament in at least a dozen countries.

But, according to the 60 signatories of the UN Single Convention on Narcotic Drugs, cannabis remains internationally illegal. The production of non-intoxicating commercial hemp, from which are derived an astonishing 25,000 different products from handcream to housing materials, is strictly controlled.

As any pothead will tell you, the practice of taking cannabis leaves (marijuana) or resin (hashish) has been popular for centuries. The drug was known to the early Arabs as the "blissful branches" or the "morsel of thought" and supposedly used by sects such as the mystical Sufis and the mythical Assassins. Some scholars believe that Christ may have treated eye and skin conditions using cannabis-based oils, and in the 17th century it was prized by the herbalist Nicholas Culpeper.

Recent research indicates that its medical benefits range from relieving cancer to alleviating muscular convulsions. It also gets you pleasantly high. Coleridge took cannabis recreationally, as did Baudelaire, Yeats and later the Beats, assuring the drug an iconic, romantic and subversive status.

In the 19th century, despite attempts to create cannabis tinctures as painkillers, hashish became confused with opium, with addiction, and with the Orient. It became a symbol of the foreigner, and was demonised as a way of suppressing ethnic minorities. Hence, Martin Booth argues, 20th-century drug law in the US reflected white fears of non-white minorities, particularly the Chinese, African-Americans and Mexicans.

It was seriously believed that the black population was conspiring with the Chinese in order to rape and enslave white girls seduced with marijuana, uniting in popular consciousness the unholy trinity of sex, drugs and violence: the period of "Reefer Madness" and hysterical fears of drug-crazed abandon. Such scaremongering grew more and more absurd, and in one case cannabis was blamed for a plague of vampires. An "expert" witness in pharmacology testified at a trial in 1938: "After two puffs on a marijuana cigarette, I was turned into a bat".

Martin Booth tells this story with admirable restraint: a story of moral panic and outrage, wild prejudice and sheer pig-ignorance that has produced some of the most grotesque legislation of the past hundred years. Here, the facts speak for themselves and present an unarguable case for a radical reassessment of the legislation governing cannabis. This book should be on the shelf of anyone interested in human freedoms and bad laws.

Nick Groom's 'The Forger's Shadow' is published by Picador