What is the law when defending yourself against intruders?

The arrest of a 78-year-old man on suspicion of murder after he allegedly stabbed a suspected burglar this week has sparked public debate.

Richard Osborn-Brooks, who was released on police bail today, reportedly “found two intruders in his house in southeast London in the early hours” of Wednesday, says the BBC.

A 37-year-old man armed with a screwdriver forced the pensioner into his kitchen, where a struggle ensued, during which the younger man was stabbed, the Metropolitan Police said.

Friends and neighbours “have spoken out in support of Osborn-Brooks”, telling the Daily Mirror: “He was just protecting himself.”

The case has highlighted questions about what rights homeowners have when protecting themselves and their property from intruders.

Although the authorities say the first port of call should always be the police, the Government and the Crown Prosecution Service (CPS) websites offer brief outlines of the “reasonable force” that can be used to protect yourself or others if a crime is taking place inside your home. 

So what is reasonable force?

There is “no specific definition of what amounts to reasonable force, as it depends on the situation and are considered on a case-by-case basis”, says The Sun.

According to the CPS, if you only did what you honestly thought was necessary at the time, this would provide strong evidence that you acted within the law.

You don’t have to wait to be attacked before defending yourself in your home. In 2016, the High Court “ruled that householders can use disproportionate force against intruders if they believe it necessary”, according to the London Evening Standard.

On its website, the CPS says: “If you have acted in reasonable self-defence... and the intruder dies, you will still have acted lawfully.”

When could you be prosecuted?

If the intruder tries to run away, you are permitted to give chase and apprehend them, although the degree of force should be lower. A “rugby tackle or a single blow would probably be reasonable”, says the Mirror.

However, the authorities say you could be prosecuted if, for example, you carry on attacking the intruder even if you’re no longer in danger.

If you set up a trap for a would-be burglar rather than calling the police, “this would not be deemed to be self-defence or reasonable force”, according to the Ask the Police information website.

This week’s arrest has recalled the notorious case of farmer Tony Martin, who killed 16-year-old burglar Fred Barras at his farmhouse in Norfolk.

Martin “shot Barras with his unlicensed shotgun in 1999, and was jailed for life”, says The Sun. Martin’s sentence was later reduced to five years for manslaughter.