Police can search you if you are found on the premises of a place which is being searched with a warrant. Police can search you or your possessions if they have a reasonable suspicion that you have an illegal narcotic on your person. Police can search you if they have a "reasonable suspicion" based on objectively verifiable evidence that you are possibly engaged in some criminal activity. So, if the police have a reasonable suspicion that you may be carrying drugs on your person or in your bags and you are in a public place such as a bus station or a park, they are allowed to use sniffer dogs to sniff the bag and on the basis of the dog’s identification are allowed to open and search the bag. (1)

In addition, where a police officer has reasonable grounds to believe that his or her safety or that of others is at risk, the officer may engage in a protective pat-down search of you when you are detained (even when you have not been put under arrest). Both the detention and the pat-down search must be conducted in a reasonable manner. 

  1. Police can search you if they have reasonable grounds to believe you are carrying a concealed or prohibited weapon.
  2. Police can search you if they have reasonable grounds to believe that you are carrying illegal drugs or alcohol that will be used for an illegal purpose.
  3. Police can also search you if you are under arrest.  Police officers are allowed to search for weapons or to preserve evidence if you have been arrested, even if they don`t have a warrant. (2)
  4. If you consent to being searched, police can search you.

What Should You Do if the Police Physically Search You Without a Warrant?

You should not physically resist the search, but if you do not consent to the search, say you do not consent. 
If you physically resist the search there is a possibility that you could be charged with assault or obstruction.  

(1) R. v. Kang-Brown, 2008 SCC 18

(2) R. v. Golden, [2001] 3 S.C.R. 679, 2001 SCC 83, at para. 95