Brian Paddick, who as a police chief pioneered the light-touch approach to drugs in Brixton, has put himself forward to be the Liberal Democrat mayoral candidate for London, the party confirmed yesterday.

A spokesman for the Liberal Democrats confirmed that the party had been in talks with Mr Paddick, who was Britain’s most senior openly gay policeman until his retirement as Metropolitan Police deputy assistant commissioner this year.

Mr Paddick, 49, left the Met after clashing with his boss, Sir Ian Blair, over the death of Jean Charles de Menezes, the Brazilian man killed in a case of mistaken identity as police hunted terrorist suspects in July 2005.

The mayoral hopeful is best known for pioneering a light-touch approach to policing cannabis in Brixton.

No other contenders have yet put themselves forward, but his public prominence could help him to win the party’s nomination.

Some Liberal Democrats believe that he would be an asset because he knows London and he has a profile that would make him able to take on Ken Livingstone for Labour and Boris Johnson for the Conservatives.

However, one source with knowledge of Mr Paddick’s mayoral bid said that it was not a foregone conclusion. “He is not a shoo-in,” they said.

This week Lembit Öpik, the colourful Montgomeryshire MP, indicated that he was interested in a London mayoral bid but had to dampen down speculation after getting scant support from the leadership.

Yesterday the Liberal Democrats released a statement saying: “We have been in talks with Brian Paddick, among others. We hope and expect him to go forward for the nomination as part of a full and open selection process which will begin shortly.”

A source suggested that Mr Paddick had made the initial approach, but would not say whether he had met Sir Menzies Campbell, the party leader.

Advertisements will be placed in papers in a week. The party will then draw up a shortlist that will be released a fortnight before next month’s party conference, during which hustings will take place. Then, everyone who has been a London member of the party for more than a year will be invited to vote. It is hoped to have a candidate in place by mid-November.

Mr Paddick was on duty as a sergeant during the 1981 Brixton riots and went on to become commander with responsibility for the South London borough of Lambeth – including Brixton – in 2000.

He sparked controversy in 2002 when he told officers not to arrest or charge people found in possession of cannabis, but to issue on-the-spot warnings and confiscate the drugs. A Crown Prosecution Service investigation that year led to Mr Paddick being cleared of press allegations that he had himself smoked cannabis.

The report published on Thursday on the aftermath of Mr de Menezes’s death by the Independent Police Complaints Commission confirmed Mr Paddick’s account that close aides of Sir Ian, the Commissioner of the Metropolitan Police, knew within hours of rumours that police had shot the wrong man.

Liberal Democrat sources said that Mr Paddick had been a party supporter “for some time”, but had not been able to join until he left the Metropolitan Police.

Lynne Featherstone, the Lib Dem MP for Hornsey & Wood Green, described him as an impressive candidate. “Brian is the one officer I met who I believe really understands and gives weight to some of the problems that are contentious,” she said on her blog. She praised him for his “avant-garde” approach to cannabis when he was commander in Lambeth and his “evidence to the stop-and-search scrutiny and subsequent work on that”.

The story so far

Name Brian Leonard Paddick

Born April 24, 1958 in Balham, South London

Educated Bec grammar school, Tooting Bec; Sutton Manor High School; Queen’s College, Oxford; Warwick University; Cambridge University (Postgraduate Diploma in Criminology)

Police career

— Constable, Metropolitan Police 1976

— Sergeant on the front line during the 1981 Brixton riot

— Ran CID at Notting Hill and responsible for policing the Notting Hill Carnival

—Promoted to commander in December 2000, and fulfilled his ambition of becoming head of policing in Brixton

— Announced departure from Metropolitan Police in April

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