Luke Flanagan (Roscommon-South Leitrim, Independent) | Oireachtas source

We are told cannabis causes psychosis and schizophrenia. This new argument was produced when all other arguments had been beaten. It is the latest version of what could be described as the "reefer madness" argument. In 2009 a study led by Dr. Martin Frischer of Keele University - perhaps he might be invited before the committee - examined the records of 600,000 patients aged between 16 and 44 years and failed to find any link between cannabis use and these conditions. According to the study, between 1972 and 2002 cannabis use in the United Kingdom increased fourfold among the general population and eighteenfold among those aged under 18 years. Based on the literature supporting a link which is repeatedly cited by opponents of legalisation, one would have to argue that this increase in usage should have been followed by an increase of 29% in the incidence of schizophrenia between 1990 and 2010.

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