JAPAN

The expansion

• J: justified
• A: authorised
• P: proportionate
• A: auditable
• N: necessary

What it is for

JAPAN is a test for the written rationale behind a decision: a use of force, a search, a deployment, the sharing of information or the release of footage. Each word is a question the record must answer: why, on whose authority, was it no more than required, can it be traced later, and was it needed at all.

This is practice shorthand. No College of Policing or force document using the mnemonic could be read on 19 October 2026; three force policies that search engines returned for it did not contain the word. The tests it stands for are in the sources below.

Where it comes from

Justified and necessary come from the statutory tests for force. Section 3(1) of the Criminal Law Act 1967 allows "such force as is reasonable in the circumstances in the prevention of crime, or in effecting or assisting in the lawful arrest of offenders". Section 117 of PACE lets a constable "use reasonable force, if necessary, in the exercise of the power". Code G paragraph 1.3 says of arrest that "The use of the power must be fully justified and officers exercising the power should consider if the necessary objectives can be met by other, less intrusive means."

Proportionate is the word the College of Policing's National Decision Model uses at its options stage, where the officer asks whether the action is "proportionate, legitimate, necessary and ethical", and Code G requires arrest to be exercised "in a non-discriminatory and proportionate manner which is compatible with the Right to Liberty under Article 5".

Authorised reflects that many powers need a named person's authority before use: a section 60 authorisation, an inspector's authority for a section 18 search, a superintendent's extension of detention. Auditable reflects the NDM's final stage, action and review, which the College describes as the point to "review your decisions, using the NDM. What lessons can you take from how things turned out?"

When it is used

Whenever an officer or member of staff records the rationale for a decision that interferes with someone's rights or property, on a use-of-force form, in a pocket notebook or on an intelligence log. It overlaps with PLAN and PLANE, which is taught for the use of force specifically; JAPAN is the broader version applied to records.

Read on this site

• National Decision Model (NDM) in the glossary
• Proportionality
• Use of Reasonable Force for PACE Powers
• PACE Code G: Arrest
• Key Cases on Police Use of Force