Legality in The United Kingdom
The legal status of ballistic knives or pilum knives is doubtful under current legislation in the United Kingdom, particularly given the degree of discretion granted to Crown prosecutors and the police with regard to classifying knives of an arguably offensive nature as prohibited items. Prosecutors are encouraged by the government to charge defendants under more than one Act where applicable. Furthermore, in the UK it is customary for the Metropolitan Police, not a barrister, to be consulted as legal experts on a question of whether a given knife is to be considered illegal under existing UK knife laws, and this has resulted in a tendency to interpret any bladed object of questionable status as falling within the definition of a prohibited knife.
Whilst "ballistic knives" are not specifically mentioned in any legislation, the marketing, sale, transfer, or possession in a public place of a ballistic knife could be construed to be illegal under the Restriction of Offensive Weapons Act 1959, the Knives Act 1997, the Criminal Justice Act 1988, and the Prevention of Crime Act 1953. The Restriction of Offensive Weapons Act 1959 imposes criminal penalties for anyone who manufactures, sells or hires, or offers for sale or hire, or lends or gives to any other person "any knife which has a blade which opens automatically by hand pressure applied to a button, spring or other device in or attached to the handle of the knife." The Knives Act 1997 prohibits the marketing of knives as offensive weapons, while the Criminal Justice Act 1988 prohibits the carrying of blades or sharply pointed objects in a public place without "good reason or lawful authority". Finally, the Prevention of Crime Act 1953 prohibits the possession in any public place of an offensive weapon without "lawful authority or reasonable excuse." The term "offensive weapon" is defined under the Prevention of Crime Act 1953 as: "any article made or adapted for use to causing injury to the person, or intended by the person having it with him for such use". Under the Prevention of Crime Act, knives otherwise 'exempt' from penalty under the Criminal Justice Act 1988 when carried for "good reason or lawful authority" may still be deemed illegal if authorities conclude the knife is being carried as an "offensive weapon" without "lawful authority or reasonable excuse". 'Lawful authority’ means those occasions where people from time to time are required to carry weapons as a matter of governmental duty, such as police officers or members of the armed forces, not private persons, hence the 'lawful authority' language cannot be relied upon to establish an exemption from prosecution of private individuals. Furthermore, as the ballistic knife was originally designed as an offensive weapon, not as a tool intended for use in a trade or business, and given current prosecutorial directives, it may be difficult to establish "reasonable excuse" for carrying such a knife before a UK prosecutor or court, especially as the carrying of a knife in public for self-defence is not acceptable as a "reasonable excuse". In the eyes of the law, claims of self-protection are presently viewed as an admission that the defendant intends to use the knife in violation of the law as an "offensive weapon" - albeit in a defensive manner, and in otherwise justifiable circumstances.
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