Tracknum: override Pubdate: Fri, 20 Jul 2001 Source: Times, The (UK) Copyright: 2001 Times Newspapers Ltd Contact: http://www.the-times.co.uk/ Details: http://www.mapinc.org/media/454 Author: T. R. C. Boyde MARIJUANA RESEARCH GIVES DRUG 'SAFE BILL OF HEALTH' Sir, Dr Jonathan Middle (letter, July 11) is right about cannabis. However liberal one wishes to be, this is a mind-altering drug; that's why users use it. Train drivers are already liable to be tested for traces and this must eventually be introduced for drivers of road vehicles, because we really cannot allow someone whose notion of reality is impaired to be in control of a lethal weapon. Cannabis differs from alcohol in that the effects last for days, and it can be detected in the body for two weeks or more. Those who use cannabis should consider carefully the increased risk of losing their driving licence before they vote for legalisation. Yours faithfully, T. R. C. BOYDE (Fellow of the Royal College of Pathologists), 93 Harley Street, W1G 6AD. July 11.