What is the test for reasonable and probable grounds to search a person in a search warrant?

The existence of reasonable and probable grounds is not a prerequisite to the existence of the power of the police to search as an incident to arrest. In Cloutier v. Langlois, 1990 CanLII 122 (SCC), [1990] 1 S.C.R. 158, L'Heureux-Dubé J. writing for the court said at para. 49: ... that the common law as recognized and developed in Canada holds that the police have a power to search a lawfully arrested person and to seize anything in his or her possession or immediate surroundings to guarantee the safety of the police and the accused, prevent the prisoner's escape or provide the evidence against him. The common thread in this line of authority is the objective of guaranteeing safety and applying the law effectively.