A teenager caught with a car boot of 20 cannabis joints should not be banned from becoming a teacher or a nurse, Nick Clegg suggested today. The Lib Dem leader was challenged over his call for drug users not to be given criminal records for possessing illegal substances. He said it was ‘ridiculous’ that young people’s future careers could be ‘blighted’ by nothing more than a ‘teenage indiscretion’. Nick Clegg was grilled about how many cannabis joints a teenager could be caught with without getting a criminal record . The Liberal Democrat manifesto will commit the party to ending imprisonment for possession of drugs for personal use and ensure that those arrested with small amounts of illicit substances do not get a criminal record. But during his weekly radio phone-in, Mr Clegg was grilled about how many cannabis joints a teenager could be caught with without getting a criminal record. LBC host Nick Ferrari said: ‘I’m an 18-year-old student, I get stopped by police, I have 20 joints in the boot of my car. I subsequently want to become a teacher. Can I become a teacher?’ Mr Clegg insisted that as the law stands that person would not be able to become a teacher. But he said the law needed to be changed: ‘I think it’s completely wrong if some teenager, 17 or 18 year old, dabbles in… I don’t know whether it’s 20 [joints] or one. ‘Do I think their chances of working as a nurse, as a teacher, or a lawyer or a taxi driver should be blighted forever, of course I don’t. ‘If you are a teenager, one in five youngster use drugs, a third of adults have used drugs at some point in their life in this country. ‘What you are saying to me is someone who as a 17 or 18--year-old and has smoked some hassish, and they are caught doing that, you’re saying they should never ever… work as a nurse, as a teacher.’ Liberal Democrat leader Nick Clergg shared a platform with Virgin boss Sir Richard Branson to argue said drug users should not be given criminal records for possessing illegal substances . Yesterday's announcement follows a controversial ‘research’ project ordered by Lib Dem Home Office ministers, which used taxpayers’ money to study drugs policy around the world. Jeremy Browne and Norman Baker jetted off to examine how other countries tackle drugs. They travelled to ten countries, including the US, Portugal and Sweden, at a cost of almost £40,000. The Lib Dems seized on parts of the report suggesting decriminalisation in countries like Portugal cut the health damage caused by drugs. But critics said they ignored evidence that the number of children using drugs had risen. Pressed again on the scenario of 20 joints, Mr Clegg hit back: ‘If he has got 20 joints is he allowed to be a teacher. ‘Your fixation is whether it was 20. My fixation is whether do I think they should be ruled out forever to work as a teacher. ‘I think it’s ridiculous that we turn what might be a teenage indiscretion into a lifelong ban from public service in our schools and hospitals. ‘I think that is one of the many, many features of our approach to the so-called war on drugs which is irrational, and counter-productive.’ Mr Clegg yesterday shared a platform with Virgin boss Sir Richard Branson  who claimed that smoking powerful cannabis does not cause ‘any harm’. The Virgin tycoon shared a platform with the Lib Dem leader to promote the party’s pledge. He said: ‘Of people taking hash [cannabis], something like 99 per cent do not have a problem ... Take people taking skunk. ‘It’s slightly worse than alcohol. But there are a lot of people doing it for recreational purposes and they enjoy doing it and it’s not doing them any harm.’ However, he today sought to clarify his remarks, insisting he was talking about 'hash' and not 'skunk'. Sir Richard said in a blog: 'What I did say was that many people take hash for recreational purposes and enjoy it without doing themselves any harm. 'The same way that drinking alcohol, if you do it in moderation, is not going to do people any harm.' A study last month by Kings College London found that 24 per cent of new cases of psychosis are linked to the use of skunk. The report concluded that smoking skunk trebles the risk of someone having a psychotic episode. Last night, Mr Clegg also insisted that the so-called ‘war on drugs’ was ‘not working’, although he was later forced to concede that official figures show drug use has been falling in Britain for years. The Home Secretary Theresa May has blocked any softening of the drugs laws. The Lib Dems want to take drug policy away from the Home Office and place it in the Department of Health . A poll of 100 charities by the Centre for Social Justice last night found that 69 per cent of charities in the field would be concerned if the Government decriminalised cannabis. More than half (56 per cent) said cannabis use would increase if its use was decriminalised. Andy Cook, chief executive of charity Twenty Twenty, which works with disadvantaged young-people, said: ‘We are scared by the idea of liberalising cannabis laws. We work tirelessly to get the most disadvantaged and disengaged young people back into learning and to hold down jobs. If they are taking cannabis it makes it almost impossible to succeed – sapping their motivation and effectively tying our hands in the support we can give. ‘Cannabis is ruining the life opportunities of those we work with, so the idea that society would be better off if this stuff was decriminalised is crazy. Making it more easily available and more culturally acceptable will mean that more of our young people would take it. The result will be that more of our young people would fail to make the most of their potential.’
Nick Clegg said users should not be given criminal records for possession . He said decriminalisation would apply to 'harder' drugs such as heroin . Deputy PM's announcement publicly endorsed by Virgin tycoon Branson .