What is the test for reasonable and probable arrest under Section 450 of the Criminal Code?

31 In Regina v. Storrey, [1990] 1 S.C.R. 24 (S.C.C.), the court dealt with the question of reasonable and probable grounds to arrest under Section 450 (now Section 495) of the Criminal Code and continuing the investigation after the arrest. Cory, J. (at p. 250) made the following comments which are helpful in the case at bar: The protection of the public is safeguarded by the requirement, alike of the common law and, so far as I know, of all statutes, that the constable shall before arresting satisfy himself that there do in fact exist reasonable grounds for suspicion of guilt. That requirement is very limited. The police are not called on before acting to have anything like a prima facie case for conviction; but the duty of making such inquiry as the circumstances of the case ought to indicate to a sensible man is, without difficulty, presently practicable, does rest on them; for to shut your eyes to the obvious is not to act reasonably. . . . . . Those grounds must, in addition, be justifiable from an objective point of view. That is to say, a reasonable person placed in the position of the officer must be able to conclude that there were indeed reasonable and probable grounds for the arrest. On the other hand, the police need not demonstrate anything more than reasonable and probable grounds. Specifically they are not required to establish a prima facie case for conviction before making the arrest. Cory, J. then refers to continued investigation. He says (at p. 254): On the contrary, it has long been the rule in Canada and the United Kingdom that the police can continue their investigation subsequent to an arrest. The essential role of the police is to investigate crimes. That role and function can and should continue after they have made a lawful arrest. The continued investigation will benefit society as a whole and not infrequently the arrested person. It is in the interest of the innocent arrested person that the investigation continue so that he or she may be cleared of the charges as quickly as possible.