“The “reasonableness” of the suspicion on which an arrest must be based forms an essential part of the safeguard again arbitrary arrest and detention which is laid down in Article 5(1)(c). The Court agrees with the Commission and the Government that having a “reasonable suspicion” presupposes the existence of facts or information which would satisfy an objective observer that the person concerned may have committed the offence. What may be regarded as “reasonable” will however depend on all the circumstances.”
“Facts and information relevant to a person’s suspected involvement in an offence should not be confined to those which tend to indicate the person has committed or attempted to commit the offence. Before making a decision to arrest a constable should take account of any facts and information that are available, including claims of innocence made by the person which might dispel the suspicion.”
“If a person, without lawful authority or excuse, in any way wilfully obstructs the free passage along a highway he is guilty of an offence and liable to a fine not exceeding level 3.”
“(1) A person commits the offence of aggravated trespass if he trespasses on land and, in relation to any lawful activity which persons are engaging in or are about to engage in on that or adjoining land, does anything there which is intended by him to have the effect – (a) of intimidating those persons or any of them so as to deter them or any of them from engaging in that activity; (b) of obstructing that activity; or (c) of disrupting that activity.” (a) of intimidating those persons or any of them so as to deter them or any of them from engaging in that activity; (b) of obstructing that activity; or (c) of disrupting that activity.”
“What the prosecution have to prove is that there was an obstructing of a constable; that the constable was at the time acting in the execution of his duty and that the person obstructing did so wilfully. To carry the matter a little further, it is in my view clear that “obstruct” undersection 51(3) of the Police Act 1964 , [a precursor ofsection 89(2) of the Police Act 1996 ], is the doing of any act which makes it more difficult for the police to carry out their duty. That description of obstructing I take from Hinchcliffe v Sheldon[1955] 1 WLR 1207 . It is also in my judgment clear that it is part of the obligations and duties of a police constable to take all steps which appear to him necessary for keeping the peace, for preventing crime or for protecting property from criminal injury. There is no exhaustive definition of the powers and obligations of the police, but they are at least those and they would further include the duty to detect crime and bring an offender to justice.”
“It is part of the obligations and duties of a police constable to take all steps which reasonably appear to him to be necessary…for preventing crime…”
“In the judgment of this court it would be difficult…to reduce within specific limits the general terms in which the duties of police constables have been expressed. In most cases it is probably more convenient to consider what the police constable was actually doing and in particular whether such conduct was prima facie an unlawful interference with a person’s liberty or property.”
“This is I think, the fundamental principle, viz., that a man is entitled to know what, in the apt words of Lawrence LJ, are “the facts which are said to constitute a crime on his part”.”
“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.”