How far can you go to lawfully protect yourself in a home invasion?

Over the weekend, New South Wales police charged a man with murder after an alleged burglar died following an incident in the man’s home in the early hours of Saturday. Conversely, in a separate case, committal proceedings are continuing against two men charged with murder allegedly committed during a home invasion in Western Sydney in 2014.

How far can homeowners lawfully go to protect themselves in a home invasion in Australia? Where is the line drawn between self-help and vigilantism?

What is home invasion?

“Home invasion” is a popular rather than legal term. It emerged in the 1990s to describe multiple offenders, carrying weapons, who unlawfully enter a home, intending to rob or injure persons inside.

Australia has no specific offence of “home invasion”. Relevant offending is usually prosecuted through offences including robbery/armed robbery, break and enter with intent, burglary/aggravated burglary, and assault.

However, two states – South Australia and Western Australia – have laws that deal specifically with the issue of self-defence to home invasion. Additionally, protection against home invasion may involve the occupier performing a citizen’s arrest.

Self-defence, defence of property, and home invasion

In most home-invasion cases, occupiers who discover a person unlawfully in their home will be acting in defence of themselves and their family – as well as protecting their property.

Although the laws of self-defence vary across Australia, most laws require in essence that the person believed on reasonable grounds that it was necessary in self-defence to do what they did. And, from their perspective, there must have been reasonable grounds for that belief.

South Australia and Western Australia – the two states that have laws specifically dealing with self-defence to home invasion – require that occupants who act in defence of themselves or another, or to protect property against an intruder, must believe on reasonable grounds that it is necessary to do so, but relax requirements of proportionality in the home occupier’s response.

The approach generally adopted in Australia differs significantly from the “stand your ground” approach to self-defence that has been influential in the US. “Stand your ground” generally encourages “self-help” by removing any requirement of retreat. It permits a person who is threatened or attacked to stand their ground and claim self-defence even where an avenue of retreat or other means of avoiding the conflict was safely available.

It is claimed that these laws originate from the old common-law castle doctrine. This effectively provided that a person attacked in their home could use reasonable force, including fatal force, to protect their life without any duty to retreat from the attacker. But, in reality, these modern laws go far beyond that 17th-century tradition.

Their popularity is underpinned by factors that are distinctive to the contemporary US: high levels of gun ownership; a belief in the constitutional right to bear arms; and decreasing public confidence in the ability of law enforcement agencies to protect the community.

Approaches to self-defence in Australia still tend to emphasise reasonable necessity and discourage vigilantism. Police advise Australian homeowners against keeping weapons for protection and instruct them to immediately contact police if they suspect an intruder is in their home.

Citizen’s arrest

Although there are significant differences, laws in each Australian state and territory broadly empower members of the community to make a citizen’s arrest where they find someone committing a crime.

Consequently, a person who apprehends an intruder unlawfully inside their house could arrest the wrongdoer and deliver them to police. As a general rule, a person may use “reasonable force” which is not disproportionate to – or unnecessary for – the purpose of the arrest.

But if the offender resists, complex issues may arise as to how much force can lawfully be used.

Determining how far a person can lawfully go in protecting themselves in a home invasion requires consideration of complex legal issues. It also involves broad matters of social policy.

By requiring that a person acting in self-defence or effecting a citizen’s arrest must act genuinely and reasonably, Australian states and territories have developed a distinctive approach that appropriately balances self-defence against vigilantism.