Offences related to carrying knives and other offensive weapons are set out in the Criminal Justice Act 1988 and the Prevention of Crime act 1953.

There are two broad categories of offence: possessing a weapon and threatening with a weapon. The specific offence will depend on the type of weapon used and where the offence was committed.

There are separate but similar offences for knives and offensive weapons. An offensive weapon is anything made or adapted to cause injury, or intended to be used as a weapon, including disguised weapons. Examples include:

  • a baseball bat, hammer or any other heavy implement if it is intended to be used as a weapon
  • acid and other corrosive substances that are intended to be thrown at someone
  • knuckledusters and other specially made weapons such as sharpened door keys

A knife is covered by these offences if it has a blade or point (including a folding pocket knife, if the blade is longer than three inches).

Possession of knives and offensive weapons encourages violence and can lead to serious injury and death, as well as facilitating other criminal offences. It is, therefore, an offence to carry a knife or an offensive weapon in a public place, even if the person carrying it claims they were not intending to use it. A person will not be convicted if the knife or weapon was carried for a lawful reason. An example could be someone who uses a knife for work, carrying it on their way to or from work. But carrying a knife or other weapon for protection is not a lawful reason.

A public place is anywhere the public has access to. Roads, schools, hospitals, football stadiums, pubs and shops are all public places.

Threatening with a weapon is a more serious offence. This is where a weapon is used to cause another person to fear that violence may be used against them.


Parliament sets the maximum (and sometimes minimum) penalty for any offence. When deciding the appropriate sentence, the court must follow any relevant sentencing guidelines, unless it is not in the interests of justice to do so.

How the courts sentence offenders depends on the type of offence.

Possessing a weapon: the maximum sentence for possession offences is four years’ custody.

If the offender has committed the same offence before or another relevant offence such as threatening with an offensive weapon in a public place, they will face a minimum sentence of at least six months’ custody.

Threatening with a weapon: the mandatory minimum sentence for threatening offences is 6 months’ custody; the maximum sentence is four years’ custody.

Find out more about the different types of sentence the courts can impose.

How is the sentence worked out?

Sentences are calculated by an assessment of culpability and harm, as well as considering any aggravating or mitigating factors.

Culpability means how responsible the offender was for the offence. The court will also consider the kind of weapon they had in their possession.

Harm is a measure of damage caused or risked to the victim or victims. If the offence took place in a prison, school or other place where vulnerable people are likely to be present this would indicate a greater level of harm. Causing serious alarm or distress also indicates greater harm.

Aggravating factors may increase the severity of the sentence. Examples include where the offence was:

  • motivated by or demonstrated hostility based on race, religion, disability, sexual orientation or identity
  • committed as part of a group
  • committed under the influence of alcohol or drugs

Mitigating factors may decrease the severity of the sentence. Examples include where the offender:

  • lacks any previous or relevant convictions
  • is of good character
  • has a serious medical condition requiring urgent, intensive or long-term treatment
  • is young or lacks maturity
  • has a mental disorder or learning disability
  • is the sole or primary carer for dependent relatives
  • has co-operated with the police

If the defendant enters a guilty plea, they will also receive a reduced sentence.

You can find out more about how sentences for knives and offensive weapons are calculated depending on the offence type. See the sentencing guidelines for:

Useful information

The information on this page is not a complete legal analysis of the offences and is not a substitute for legal advice.  The law will be different in Scotland and Northern Ireland.