Although the chief officers of police are answerable to the law, there are many fields in which they have a discretion with which the law will not interfere. For instance, it is for the Commissioner of Police of the Metropolis, or the chief constable, as the case may be, to decide in any particular case whether inquiries should be pursued, or whether an arrest should be made, or a prosecution brought. It must be for him to decide on the disposition of his force and the concentration of his resources on any particular crime or area. No court can or should give him direction on such a matter. He can also make policy decisions and give effect to them, as, for instance, was often done when prosecutions were not brought for attempted suicide.’
. . And ‘No Minister of the Crown can tell him that he must, or must not, keep observation on this place or that; or that he must, or must not, prosecute this man or that one. Nor can any police authority tell him so. The responsibility for law enforcement is on him. He is answerable to the law and to the law alone.’
The decision as to the offence for which a person is to be prosecuted is a matter for the prosecuting authority, which has a wide discretion in the matter
Answerability of Chief Constables The constitutional status of the Commissioner had never been defined, either by statute or by the courts. By common law police officers owe to the general public a duty to enforce the criminal law. The court considered the extent to which a court could interfere...
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