Defence of Life

Defence of life is the use of force to protect oneself or another person from death or serious injury. In England and Wales it sits within the wider law of self-defence, defence of another, prevention of crime and lawful arrest.

The central rule is that a person may use force that is reasonable in the circumstances as they honestly believed them to be. The law accepts that people under attack do not make calm, perfect measurements. It does not protect revenge, punishment after the danger has passed, or force that is unreasonable on the facts as the defender believed them.

Legal Basis

The law comes from both common law and statute.

Section 3 of the Criminal Law Act 1967 allows a person to use reasonable force in the prevention of crime, or in effecting or assisting the lawful arrest of offenders, suspected offenders, or people unlawfully at large.

Section 76 of the Criminal Justice and Immigration Act 2008 explains how courts should approach reasonable force in self-defence, defence of another, defence of property, prevention of crime and lawful arrest. It does not abolish the older common-law and statutory defences. It sets out how the reasonableness question is to be judged.

The Two Main Questions

In practical terms, self-defence normally turns on two questions.

First, did the person honestly believe that force was necessary? A mistaken belief can still be relied on if it was genuinely held, although the reasonableness of the belief can be evidence when deciding whether it was genuinely held. A mistaken belief caused by voluntary intoxication is treated differently and cannot be relied on in the same way.

Second, was the amount of force reasonable in the circumstances as the person believed them to be? This is not decided only by what the defender personally thought was acceptable. The court or jury considers the facts as the defender believed them, then asks whether the force used was reasonable on that basis.

Protection of Others

Defence of life includes protecting another person. A person may intervene where they honestly believe someone else is being attacked or is about to be attacked. The same reasonableness test applies.

This is important in public incidents, shop incidents, domestic violence situations, road-rage attacks, and cases where a vulnerable person cannot protect themselves. The law does not require a person to stand by while another person is being seriously assaulted, but it does require the intervention to remain within reasonable limits.

No Duty to Retreat

There is no strict duty to retreat before using force for a legitimate defensive purpose. Section 76 makes clear that a possibility of retreat is only a factor in deciding whether the force used was reasonable.

That means a person is not automatically acting unlawfully because they did not run away. It also means that if a safe and obvious way to avoid violence existed, the court may consider that when judging necessity and reasonableness.

Householder Cases

The law gives householders a different test when force is used against an intruder in a dwelling. In a householder case, force is not automatically unreasonable merely because it is disproportionate. However, force that is grossly disproportionate remains unlawful.

This does not create a free right to punish burglars or continue violence after danger has passed. It recognises that a person facing an intruder at home may be frightened, under-informed and forced to act quickly.

Serious or Lethal Force

Serious force may be reasonable where the defender honestly believes there is a serious threat to life or limb. The question is not whether the defender used the least possible force with hindsight, but whether the force was reasonable in the circumstances as they believed them to be.

Force becomes much harder to justify once the threat has ended. Chasing someone down to punish them, attacking after they are restrained, or continuing violence when the danger has clearly passed will usually point away from defence and towards retaliation.

Weapons and Carried Items

The defence of life question is separate from whether a person was lawfully carrying a particular item. A person may have a defensive argument about force used during an attack, while still facing a separate question about possession of an offensive weapon, a bladed article, or another controlled item.

The reverse is also true. The fact that an item was lawful to possess or carry does not automatically make every use of it reasonable. The court still looks at necessity, the perceived threat, the force used, and whether the action was defensive rather than punitive.

Examples

Examples help show how the test works:

• A person who pushes an attacker away to stop an assault may be using reasonable force.
• A person who restrains someone who is punching a stranger may be acting in defence of another and prevention of crime.
• A person who uses severe force because they honestly believe they are about to be killed or seriously injured may have a defence, depending on whether the force was reasonable on those believed facts.
• A person who continues attacking after the attacker is down, disarmed and no longer a threat may lose the protection of self-defence.
• A person who intervenes in a confusing fight may rely on an honest mistake, but the evidence will matter when deciding whether that mistake was genuinely held.

After the Incident

Police and prosecutors look at the whole context: injuries, witness evidence, CCTV, prior threats, the speed of events, what the defender knew, whether force stopped when the danger stopped, and whether the account is consistent with the physical evidence.

The core issue is not whether the defender was brave, frightened or morally sympathetic. The issue is whether the prosecution can disprove lawful defence once it is properly raised on the evidence.

See Also

• Reasonable Force
• Citizen's Arrest
• Police and Criminal Evidence Act 1984
• Attacks on Emergency Workers

References

• Legislation.gov.uk: Criminal Law Act 1967, section 3
• Legislation.gov.uk: Criminal Justice and Immigration Act 2008, section 76
• College of Policing: legal framework
• GOV.UK: Use of force in self defence at place of residence
• Crown Prosecution Service: householders and the use of force against intruders