John Prescott, the Deputy Prime Minister, will not face a criminal investigation into his two-year affair with a secretary, Scotland Yard said today.

Deputy Assistant Commissioner John Yates said that it would not be an appropriate use of police resources to follow up a complaint about Mr Prescott’s conduct in public office lodged by a retired police officer.

The police were swiftly accused of double standards, having prosecuted two officers
earlier this year for having sex while on duty.

In a statement, Mr Yates said: "It is considered that the potential consequences in respect of the alleged behaviour, even if proved, would not be so serious as to call for a prosecution.

"A distinction has to be drawn between action that could potentially discredit an office holder and those actions that constitute criminality."

Mr Prescott admitted two weeks ago to having had an affair with his former diary secretary, Tracey Temple. Ms Temple later told a newspaper that the pair had sex in his Whitehall office and his grace-and-favour flat in London.

The prospect of a criminal investigation into the affair arose when Alistair Watson, a retired Glasgow police officer, lodged a formal complaint with the Metropolitan Police Commissioner, Sir Ian Blair.

He said that there was no reason why the Deputy Prime Minister - and Ms Temple - could not be prosecuted for misconduct in public office and suggested that the £250,000 paid to Ms Temple by The Mail on Sunday for her diaries should be forfeited.

"I think in the interest of equality and justice, there is no reason why Mr Prescott and Miss Temple cannot be prosecuted," he wrote.

"This is not a malicious thing. If there are rules that apply to ordinary people, somebody like John Prescott should be treated the same, or more harshly."

But Mr Yates replied today: "I have considered the allegations you have raised very carefully and have sought advice from both the Crown Prosecution Service and our own lawyers.

"Misconduct in public office is a serious offence. The threshold around misconduct is a high one and there must be a serious departure from the accepted standards. In addition, the consequences likely to follow are relevant when determining whether the conduct amounted to an abuse of the public’s trust or not."

He added: "Accordingly I have decided not to embark upon a criminal investigation. To do so would not I believe be a proportionate response or an appropriate use of police resources.

The political pressure on Mr Prescott continues, however. Clare Short, a former cabinet colleague, called today for him to be stripped of his salary and perks after losing control of his Whitehall department in Friday’s post-election reshuffle.

She said it was profoundly wrong for Mr Prescott - who remains Deputy Prime Minister - to be allowed to continue to enjoy the taxpayer-funded perks including two grace-and-favour homes.

Earlier today Tony Blair defended Mr Prescott from attacks by the Tories at Prime Minister's Questions. "I prefer Prezza to Hezza," he told MPs after his Deputy was compared with Tory predecessor Lord Heseltine.

Richard Barnes, the Tories’ policing spokesman on the London Authority, said the law should be applied equally to all public officials, including ministers.

He said: “I’m not sure Prescott should be hauled into the court, but it is not acceptable that he has escaped any real punishment when two rank and file police officers lost their jobs, pensions and got criminal records for doing a similar thing.

“This represents appalling double standards, it’s one rule for Government ministers and another for the rest of us.”

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