This is not exactly true.

* Canadian' border can ask you for your local passwords.

* You can refuse - at which point, if you are Canadian/PR, you are allowed to enter the country but your device is confiscated and sent to Ottawa for further examination.

* They can NOT ask for online passwords (like your dropbox account for example). THAT SAID, if you give them your local password, and you are logged in to Dropbox, it's fair game.

Furthermore, this has not been through the Supreme Court to set precedence.