People should be entitled to use any force necessary to defend themselves against burglars, England's most senior police officer has said.

Met commissioner Sir John Stevens said homeowners should be presumed to have acted legally, even if a burglar dies, unless there is contrary evidence.

Laws which often seemed to favour criminals should be clarified, he said.

People should be prosecuted only when there was evidence of gratuitous violence, he told the Daily Telegraph.

Under the current law, homeowners are entitled to use "reasonable force" to defend themselves and their homes.

It is up to judges and juries to decide what level of force is "reasonable" in any given situation.

Sir John said the public and police were confused about what that meant and the law needed to be clarified.

The law was currently sending the wrong message by encouraging burglars to break into houses in the belief that no householder could harm them, he said.

'Public unclear'

He told the paper: "My own view is that people should be allowed to use what force is necessary and they should be allowed to do so without any risk of prosecution.

"The test at the moment is that you use reasonable force in the circumstances. You do not use excessiveness."

He said that was too imprecise for people to consider in extreme circumstances, when they needed to be clear about their legal rights.

He was speaking five days after City financier John Monckton was stabbed to death by an intruder during an attempted robbery at his home in Chelsea, west London.

In October, school teacher Robert Symons was killed in his home in nearby Chiswick.

Tony Martin

"Now is the time, specifically with these two cases we have had recently - in Chiswick and Chelsea - for the law to be clarified," he said.

He said the case of Tony Martin, the Norfolk farmer jailed for shooting dead a burglar in 1999, had distorted the self-defence issue.

"[He] did shoot the burglar as he was running away. He did use a gun that was illegal.

"The Martin case skewed everything and it was the wrong case to concentrate on."

Sir John's comments on the issue were welcomed by Malcolm Starr, a friend and supporter of Mr Martin, who recently encountered a burglar at his own home.

"Unless you face a situation like this you wouldn't know what you would do at the time," he said.

"With hindsight, I would have liked to have killed the burglar. The hatred for him being there, and attacking my wife was so great.

"I would have liked to have done him serious damage."

Mr Starr, from Wisbech, Norfolk, said an officer later told him the intruder was "probably high on drugs", which adds to the danger.

"I can't believe that anyone faced with that horrific ordeal worries about reasonable force," he said.

'More confusion'

John Cooper, a leading criminal barrister and representative of the Bar Council, told the BBC the current law means "it is all down to 12 people on a jury deciding on the facts what is reasonable".

He said many lawyers shared his view that this works well.

A law change could lead to more confusion and cause problems in various situations, he said, such as would a house guest who also attacks a burglar, have the same "burden of proof" as the homeowner?

"In the process of trying to make the law clearer, it is certainly our view, that it could make it more complicated," he said.

He said "months in months out," the Crown Prosecution Service deals with cases where a burglar was injured but the cases were not brought to court.

"In actual fact the law is working well, " he said.

'Months of trauma'

The shadow attorney general Dominic Grieve, himself a barrister, welcomed Sir John's comments and said he would like to see a law change.

He said although householders who may injure a burglar may not eventually be prosecuted they often faced "months of trauma" while a case is decided.

He said the law as it stands "sends out a very bad signal" and that the Tories were looking at legislation, offering greater protection to householders.

He added: "I do think the law is capable of being changed to make clear that reasonableness allows the householder..to use considerable force, and as long as that force isn't grossly excessive, it is proper."

Retaliation

A spokesman for the Home Office said: "The government believes that those who have been protecting themselves and their property reasonably and proportionately should not be at risk of becoming the accused.

"Under the law at present people are perfectly entitled to use reasonable force to protect themselves, their property or their family.

"What the law does not permit is an act of retaliation."

Home Secretary David Blunkett announced a major review of the law on murder in October, saying many people had called for clarification on issues such as provocation and self-defence as it relates to murder and manslaughter.