Jacqui Smith, Home Secretary, July 2007: "I did when I was at university. I think it was wrong that I smoked it when I did. I have not done for 25 years. I share other people’s concerns about the effect that cannabis has on young people and mental health problems.

“On the whole I think people think human beings should do jobs like this. I am not proud about it, I did the wrong thing. One of the things about being a politician is that you are often criticised for not knowing what’s going on. I hope that my experiences in my life have actually helped me understand that I do want crime tackled.”

Tony McNulty, Home Office Minister, follows his boss, Ms Smith, by admitting hours later that he had tried cannabis "once or twice".

Patricia Hewitt, then Health Secretary, April 2007: "I tried cannabis once when I was a student. It didn't do anything for me and I never tried it again. I've not used any other illegal drug."

Vernon Coaker, Home Office Minister for drugs policy, May 2006: "When I was a student, I took one or two puffs of marijuana but that was it. I think it was once or twice."

Caroline Flint, then Home Office minister for drugs policy, July 2003: said that she took cannabis 20 years ago when she was a student, and didn't like it.

Tory front bench, October 2000: Ann Widdecombe, shadow Home Secretary, proposes making anyone in possession of an illegal drug pay a £100 on-the-spot fine. William Hague, the party leader, retracts the policy after eight members of his Shadow Cabinet, including David Willetts, Oliver Letwin, Francis Maude, Archie Norman, Bernard Jenkin, Tim Yeo, Peter Ainsworth and Lord Strathclyde, all admitted having smoked it when younger.

Mr Ainsworth said: "I never bought my own. It was only occasionally at parties when I was at university. I did not enjoy it. Cannabis was around. It is best to be honest."

Mr Maude said: "It was hard to go through Cambridge in the 70s without doing it a few times."

Mr Yeo said: "I was offered it on occasion and enjoyed it. I think it can be a much more pleasant experience than having too much to drink. I found it agreeable."

Days after, Yvette Cooper, then health minister: "I did try cannabis while at university, like a lot of students, and it is something that I have left behind." She is now the Cabinet minister for housing and planning.

Jon Owen Jones, Welsh Office Junior Minister: “I smoked it on several social occasions when I was a student and a young man, as did many of my friends and colleagues. I would not have taken it more than once if I did not like it.”

Mo Mowlam, Cabinet Office minister and head of the Government's anti-drugs campaign, January 2000: "I tried marijuana, didn't like it particularly and, unlike President Clinton, I did inhale. But it wasn't part of my life."

Charles Clarke, then a new backbencher but later Home Secretary, May 1997: "I was asked if I had ever taken drugs and I replied I had taken it a couple of times in my late teens. It is important to tell the truth."

...and one politician who has not admitted to it...

David Cameron, Conservative leader, February 2007: refused to confirm or deny a report in a biography that he was punished at Eton for smoking cannabis aged 15, in an incident in which other pupils were expelled.

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