What does Section 8 of the Charter protect against?

Section 8 of the Canadian Charter of Rights and Freedoms protects everyone in Canada from unreasonable search and seizure by the state. The full text reads: 'Everyone has the right to be secure against unreasonable search or seizure'. Section 8 applies whenever the state intrudes on a reasonable expectation of privacy. The standard for a constitutional search is set by Hunter v. Southam Inc. (1984): the state must obtain prior judicial authorisation, based on reasonable and probable grounds established under oath, by a person capable of acting judicially, on the basis of credible evidence.

The Supreme Court of Canada has applied section 8 across many contexts. R. v. Edwards (1996) set out the test for a reasonable expectation of privacy, considering factors including ownership, presence, control, and historical use. R. v. Patrick (2009) addressed garbage left at the curb. R. v. Tessling (2004) addressed thermal imaging from aircraft. R. v. Spencer (2014) recognised a reasonable expectation of privacy in subscriber information held by internet service providers. R. v. Marakah (2017) recognised a reasonable expectation of privacy in text messages on a recipient's phone.

Several search categories operate without prior judicial authorisation. Search incident to lawful arrest is allowed where there is some reasonable basis connected to the arrest (R. v. Caslake, 1998). Border searches are subject to lower expectations of privacy under R. v. Simmons (1988) and the Customs Act. School searches by school authorities follow the modified test in R. v. M. (M.R.) (1998). Roadside breath screening, regulatory inspections, and exigent circumstances all permit warrantless searches under specific statutory or common-law frameworks.

Evidence obtained in breach of section 8 may be excluded under section 24(2) of the Charter. The current test for exclusion was set out in R. v. Grant (2009), which directs courts to weigh three factors: the seriousness of the Charter-infringing conduct, the impact on the accused's protected interests, and society's interest in the adjudication of the case on its merits. R. v. Cole (2012) addressed warrantless searches of work computers. R. v. Fearon (2014) addressed searches of cell phones incident to arrest. R. v. Reeves (2018) addressed shared computers in a household. The federal Privacy Act, PIPEDA, and provincial privacy statutes operate alongside section 8 in non-criminal contexts.