[...] the search of cell phones, like the search of computers, implicates important privacy interests which are different in both nature and extent from the search of other “places” [...]. It is unrealistic to equate a cell phone with a briefcase or document found in someone’s possession at the time of arrest. As outlined in Vu, computers — and I would add cell phones — may have immense storage capacity, may generate information about intimate details of the user’s interests, habits and identity without the knowledge or intent of the user, may retain information even after the user thinks that it has been destroyed, and may provide access to information that is in no meaningful sense “at” the location of the search [...]Moreover, the Supreme Court at para 53 recognizes that the law should not treat a smartphone differently whether it is password protected or not:
An individual’s decision not to password protect his or her cell phone does not indicate any sort of abandonment of the significant privacy interests one generally will have in the contents of the phone.But the good news ends there. In a ruling released today, the Supreme Court held in R. v. Fearon, 2014 SCC 77 at para 64 & 83 that the police can search a smartphone without a warrant when arresting a suspect, and that this does not infringe on our constitutional rights against unreasonable search and seizure (which is what s. 8 of the Charter is all about):
I therefore reject the idea that s. 8 of the Charter categorically precludes any search of a cell phone seized incidental to a lawful arrest. [...] To summarize, police officers will not be justified in searching a cell phone or similar device incidental to every arrest. Rather, such a search will comply with s. 8 where: (1) The arrest was lawful; (2) The search is truly incidental to the arrest in that the police have a reason based on a valid law enforcement purpose to conduct the search, and that reason is objectively reasonable. The valid law enforcement purposes in this context are: (a) Protecting the police, the accused, or the public; (b) Preserving evidence; or (c) Discovering evidence, including locating additional suspects, in situations in which the investigation will be stymied or significantly hampered absent the ability to promptly search the cell phone incident to arrest; (3) The nature and the extent of the search are tailored to the purpose of the search; and (4) The police take detailed notes of what they have examined on the device and how it was searched.This is in contrast to a series of rulings by the Supreme Court recently in R. v. Spencer, 2014 SCC 43, R. v. Vu, 2013 SCC 60, and R. v. Telus, 2013 SCC 16, where the court concluded that searches of a computer in a residence required a separate warrant for computer data, and searches of records at a telecommunications provider also required a warrant. Fearon was a narrow 4-3 decision with a strong dissent, and in time it may be overturned. However, given the state of the law at the moment, it would be prudent to lock your phone with a strong password (instead of a biometric feature like a fingerprint or a weak 4 digit passcode), and to enable strong data protection/encryption. Finally, keep in mind that if questioned by the police, you are under no obligation to answer any questions, incriminate yourself, or to disclose your password to the authorities.