This is the verdict of researchers who have been studying cannabis use among young people, and are due to report their findings later this month. The government is considering making cannabis a class B drug, rather than class C. This would reverse a decision made in 2004. But a study of 182 young people aged between 11 and 19, carried out for the Joseph Rowntree Foundation, concluded it was doubtful whether reclassification would have any impact on teenagers using patterns or methods...