Expanded citizen’s arrest powers could open a legal can of worms – here’s what to know
- Written by: Weekend Times
It has a dull title – the Crimes Amendment Act 2026 – but one aspect of its provisions has had plenty of publicity: the expanded right to make “citizen’s arrests”.
Aimed primarily at giving retail staff greater powers to combat petty crime, and security guards more power to hold people, the amendments raise an important question: what are the risks if people misunderstand or misuse these new powers?
In fact, “citizens” do not really have powers of arrest – unless they are asked by a police officer to help arrest someone committing (or suspected of having committed) an imprisonable offence or disturbing the peace.
This is covered under section 315 of the Crimes Act 1961. What has changed is the defence available to someone detaining or using force against someone else, which might otherwise be a criminal offence in its own right.
The main change is to section 35 of the Crimes Act. Previously, it provided a defence in limited circumstances: at night (defined as between 9pm and 6am) if someone was committing an offence against the Crimes Act; and during the day only if the offence carried three years’ imprisonment or more.
In reality, most people don’t know which offences committed during the day would qualify – and offences such as low-value theft and common assault would not.
Complicating factors
The new wording provides a defence whatever the time of day and whatever the maximum sentence for the offence. But three complexities remain:
it only applies if the person is “found committing” an offence – a past offence will not do
it only applies to offences under the Crimes Act – driving offences, drugs offences or offences against multiple other laws require you to know if they have their own separate defences
and “reasonable suspicion” is not enough – if no offence is being committed, there is no defence.
There are other potential complications. For example, what if the alleged offender is very young? If they’re under ten, the law says they cannot commit an offence; under 14, they cannot commit an offence if they don’t know their action is wrong or against the law.
What if they are mentally impaired to the extent they cannot stand trial and be convicted? All these factors could lead to court cases to determine the correct interpretation.
The Crimes Amendment Act 2026 also adds an obligation to section 35 and various other limited defences in the Crimes Act, requiring the arresting person to contact the police “as soon as practicable” and to follow their directions. If not, the protection of the defence is lost.
What about using force?
The use of force is regulated separately by section 39 of the Crimes Act. It allows “such force as may be necessary to overcome any” resistance.
That means unnecessary force is illegal. Importantly, this is not what the person using the force thinks is necessary – it means what is objectively necessary.
The law prevents this defence if “reasonable means in a less violent manner” could be used. And it forbids force intended or likely to cause death or serious bodily harm, unless the police call on you to assist.
This has been changed to specify that the force used can include “physical or mechanical restraints”. But the limitation of force being necessary remains.
Of course, something necessary in the heat of the moment may become unnecessary once people are calm. We can expect to see future legal cases about whether a continued use of restraint was necessary.
There has also been a change to defences relating to property, such as in a shoplifting situation.
Section 52 of the Crimes Act allows “reasonable force” to be used to stop the theft or recover the property. Previously, it expressly prevented striking or causing bodily harm. A grapple was fine, but not a punch.
It has been amended to remove the prohibition on striking or doing bodily harm – but it still has to be reasonable force. So a punch (or more) will still be unlawful if not found reasonable.
A legal can of worms
What if the person detaining or using force against someone steps outside the limits of these defences?
Detaining someone unlawfully and without consent, intending to confine them, is kidnapping. That carries up to 14 years’ imprisonment.
Unlawful use of force starts as common assault, which under the Crimes Act carries a one-year sentence. There are more serious offences if the force causes an injury or serious harm.
Finally, we need to remember these amendments cut both ways: a person who is wrongly detained or has improper force used against them can also rely on the expanded provisions to try to arrest the person who has challenged them.
They may also try to claim self-defence, which allows reasonable force against a perceived assault. If everyone believes the law is on their side, the result could be escalating consequences.
There is a more fundamental problem here. Police officers have training in methods of restraint, partly because some actions can be very dangerous. For example, positional asphyxia can kill people who cannot breathe properly, and some people are more susceptible to it.
Situations that warrant a citizen’s arrest or the use of force will generally be stressful enough. It’s debatable whether a potential legal can of worms improves matters.
Kris Gledhill is a member of the Executive Committee of the Criminal Bar Association, and is working on a criminal justice project funded by the Borrin Foundation. The views express here are his own..
