This week a pensioner was arrested on suspicion of murder after a man died during an attempted burglary of the 78-year-old’s home. Police confirmed that an intruder, aged 37, had died following an altercation with the homeowner, named as Richard Osborn-Brooks. 

The incident has raised questions about what people should do when they discover burglars in their home – and what rights they have when confronting them. The pensioner’s neighbours have been quick to come to his defence, arguing that he should not be punished for protecting his home. 

The law gives people the right to use force in their own defence if it is not “grossly disproportionate”, but does not spell out specifically what this is. The Metropolitan Police does not issue advice on this topic, but other forces and authorities do. 

Hertfordshire Constabulary tells people it is “generally best not to challenge an intruder”, to dial 999 if you can reach a phone safely and to “keep calm and do not take any unnecessary risks”.

It also advises people to dial 999 if they believe someone is outside trying to get inside, rather than go out to confront them.

“If the criminal complains that you have used unreasonable force, the police must investigate,” the force warns.

The official Government advice says people can defend themselves “in the heat of the moment” using an object as a weapon or tackle people who are trying to flee.”

“You don’t have to wait to be attacked to defend yourself, however you could face prosecution if you keep attacking “even if you’re no longer in danger,” it adds.

Among the most famous cases of people attacking intruders is Tony Martin, who used a pump-action shotgun and shot two people who had broken into his isolated farmhouse in Norfolk. He killed one – who was only 16 at the time – and seriously injured the other.

His murder conviction was later reduced to manslaughter, but only on grounds of diminished responsibility, due to his fragile mental state at the time. Judges called his action “wholly unjustified”. 

Businessman Munir Hussain was jailed for 30 months in 2008 after chasing and attacking Walid Saleem, one of three intruders who had threatened his family, with a cricket bat.

Saleem, who was beaten so badly he suffered a skull fracture, received a lesser sentence than Hussain, who was convicted of grievous bodily harm. This was later reduced on appeal.

Both cases caused a national debate, prompting the government in 2012 to offer better protection to those defending their homes.

In 2013, the law changed, meaning anyone who attacked an intruder would be judged on whether their use of force was “grossly disproportionate”. 

In 2016, the High Court dismissed a challenge to the law, brought by the family of Denby Collins, who was left in a coma after he entered a house in Kent and was held in a headlock for six minutes by a man who lived there with his family.

Police investigated but prosecutors declined to charge the man.

Guidance from the Crown Prosecution Service says: “If householders have acted honestly and instinctively and in the heat of the moment, this will be the strongest evidence for them having acted lawfully and in self-defence.” 

Norman Brennan, a Met Police officer for 31 years who used to the run the Victims Of Crime Trust, told HuffPost the law effectively let people respond with “the force you believe is necessary” regardless of the fact “the force you believe is necessary will be different from someone else’s”.

Brennan had closely followed such cases and had, besides the Tony Martin case, never, in 25 years, seen someone convicted of murder and manslaughter over the death of an intruder in their home.