Knives, offensive weapons and serious violence

The Labour government has committed to halving knife crime in a decade.

This briefing provides an overview of legislation concerning knives and offensive weapons, and the approaches taken by the police and other agencies to prevent serious violence in England and Wales.

What are knife crime offences?

It is a criminal offence to possess any knife or other bladed article in a public place, under section 139 of the Criminal Justice Act 1988. It is also a criminal offence to have an “offensive weapon” in any public place, under section 1 of the Prevention of Crime Act 1953.

Both offences carry maximum penalties of up to four years’ imprisonment. It is a defence for someone to prove they have possessed a knife, bladed article or offensive weapon with “good reason or lawful authority”, though the legislation does not provide examples of what this means in practice. A court determines whether the explanation provided by a defendant amounts to lawful authority or reasonable excuse based on the specific circumstances of a case.

It is also a criminal offence to possess in private any prohibited weapon under section 141 of the Criminal Justice Act 1988 (as amended by the Offensive Weapons Act 2019). Prohibited weapons are also illegal to sell, hire, lend or manufacture. The maximum penalty is 51 weeks’ imprisonment.

There are currently 20 prohibited weapons listed in secondary legislation under the Criminal Justice Act 1988 (Offensive Weapons) Order 1988, including a range of knives, bladed articles and other weapons. Under section 141(2) of the 1988 act, the government can introduce secondary legislation to add further weapons to this list. In 2024, the government added a new definition of “zombie-style” knives and machetes to the list, and launched a consultation on adding “ninja swords” to the list.

Sentencing statistics from the Ministry of Justice shows that in the year ending March 2023, there were almost 18,500 cautions and convictions made for possession of a knife or offensive weapon. Juveniles (aged 10-17) were the offenders in around 17.3% of cases.

Further data for England and Wales related to knife-related offences can be found in the Library briefing: Knife Crime Statistics: England and Wales.

What are the restrictions on the sale of knives in the UK?

Knives and bladed articles can be legally bought and sold by anyone over 18 years of age, in physical premises and online. Any retailer that sells such an item to someone under the age of 18 may commit an offence under section 141A of the Criminal Justice Act 1988. This is enforced by both the local Trading Standards team and the police.

Part 3 of the Offensive Weapons Act 2019 creates additional requirements for online retailers and delivery companies to demonstrate they have taken “all reasonable precautions and exercised all due diligence” to avoid selling or delivering knives to people under the age of 18.

Retailers must not market knives in a way that encourages their use for violence, as set out under the Knives Act 1997. In addition, online platforms and social media companies have a duty under the Online Safety Act 2023 to prevent the sale of offensive weapons and knives to people under 18.

In November 2024, the government published a consultation on legislative proposals to give the police the power to compel online platforms and marketplaces to remove illegal content related to knives and weapons, and to take civil action against senior executives of companies that do not comply.

What enforcement powers do authorities have?

Police officers have specific powers to stop and search people whom they have reasonable grounds to suspect possess a knife or bladed article, under section 1 of the Police and Criminal Evidence Act 1984.

In certain circumstances, the police can also search without reasonable grounds, when authorised by a senior officer under section 60 of the Criminal Justice and Public Order Act 1994, or when stopping an individual who is subject to a Serious Violence Reduction Order.

Stop and search is considered by many experts as an imprecise tactic, with a disproportionate impact on Black men and boys. The Library briefing Police powers: stop and search provides further information on stop and search powers.

Knife crime offences carry potentially heavy penalties, including lengthy prison sentences. Guidance published by the National Police Chiefs’ Council, College of Policing and the Crown Prosecution Service (PDF) recommends that knife crime offences should be prosecuted in all cases, except where the perpetrator is a child and it is their first offence, in which case a caution or alternative disposal can be applied.

A second conviction for a knife possession offence, or a first conviction for the  offence of threatening with a bladed article, can result in a mandatory minimum custodial sentence, as detailed under the Sentencing Act 2020.

What are the government’s strategies for preventing serious violence?

Following its Serious Violence Strategy, published in April 2018, the Conservative government established various initiatives aimed at preventing knife crime and serious violence, such as legislating for the Serious Violence Duty and funding Violence Reduction Units and the Youth Endowment Fund.

In September 2024, the Labour government launched the Coalition to Tackle Knife Crime. It said that the coalition will bring together the police, health and education service, with charities, young people, victims’ families, technology companies, and sports organisations “to develop an extensive understanding of what causes young people to be dragged into violence”.

In the 2024 King’s speech, the government said it would “create arrangements for local Young Futures prevention partnerships to bring together services to support at-risk teenagers”. The government said these measures would be introduced through a Crime and Policing Bill, though it’s not yet clear which of these commitments would require primary legislation. The bill has not yet been introduced to Parliament.