Currently it is not an offence to possess a catapult in public, and the police must prove either intent to use one to cause damage or harm, or evidence it has been used to cause damage or harm. The aim is to make it an absolute offence, like knives, to possess one in public without a lawful defence
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Ashford, Kent is seeing significant rise in young people using catapults to damage car windows and buildings. The shots can be made from a distance, and projectiles travel at speeds which could cause intentional or reckless damage to life or animals. They are easily concealed and not unlawful to carry currently, making it impossible for the police to act proactively, or seize. Even if found, police then have to prove intent which is a higher burden of proof. They can cause lots of damage.