“Where a police officer, with reasonable cause, suspects that an arrestable offence has been committed, he may arrest without warrant anyone whom he, with reasonable cause, suspects to be guilty of the offence.”
“The relevant principles are not significantly in dispute and may be summarised as follows: (i) The detention of a person is prima facie tortious and an infringement of section 4(a) of the Constitution of Trinidad and Tobago. (ii) It is for the arrestor to justify the arrest. (iii) A police officer may arrest a person if, with reasonable cause, he suspects that the person concerned has committed an arrestable offence. (iv) Thus the officer must subjectively suspect that that person has committed such an offence. (v) The officer’s belief must have been on reasonable grounds or, as some of the cases put it, there must have been reasonable and probable cause to make the arrest. (vi) Any continued detention after arrest must also be justified by the detainer.”
“My Lords, the test which section 12(1) of the Act of 1984 has laid down is a simple but practical one. It relates entirely to what is in the mind of the arresting officer when the power is exercised. In part it is a subjective test, because he must have formed a genuine suspicion in his own mind that the person has been concerned in acts of terrorism. In part also it is an objective one, because there must also be reasonable grounds for the suspicion which he has formed. But the application of the objective test does not require the court to look beyond what was in the mind of the arresting officer. It is the grounds which were in his mind at the time which must be found to be reasonable grounds for the suspicion which he has formed. All that the objective test requires is that these grounds be examined objectively and that they be judged at the time when the power was exercised. This means that the point does not depend on whether the arresting officer himself thought at that time that they were reasonable. The question is whether a reasonable man would be of that opinion, having regard to the information which was in the mind of the arresting officer. It is the arresting officer's own account of the information which he had which matters, not what was observed by or known to anyone else. The information acted on by the arresting officer need not be based on his own observations, as he is entitled to form a suspicion based on what he has been told. His reasonable suspicion may be based on information which has been given to him anonymously or it may be based on information, perhaps in the course of an emergency, which turns out later to be wrong. As it is the information which is in his mind alone which is relevant however, it is not necessary to go on to prove what was known to his informant or that any facts on which he based his suspicion were in fact true. The question whether it provided reasonable grounds for the suspicion depends on the source of his information and its context, seen in the light of the whole surrounding circumstances.”
“It is not of course to be expected that a police constable in the heat of an emergency, or while in hot pursuit of a suspected criminal, should always have in mind specific statutory provisions, or that he should mentally identify specific offences with technicality or precision. He must, in my judgment, reasonably suspect the existence of facts amounting to an arrestable offence of a kind which he has in mind.”