The cell phones we carry with us constantly are the most perfect surveillance device ever invented, and our laws haven't caught up to that reality. That might change soon.
This week, the Supreme Court will hear a case with profound implications on your security and privacy in the coming years. The Fourth Amendment's prohibition of unlawful search and seizure is a vital right that protects us all from police overreach, and the way the courts interpret it is increasingly nonsensical in our computerized and networked world. The Supreme Court can either update current law to reflect the world, or it can further solidify an unnecessary and dangerous police power.
The case centers on cell phone location data and whether the police need a warrant to get it, or if they can use a simple subpoena, which is easier to obtain. Current Fourth Amendment doctrine holds that you lose all privacy protections over any data you willingly share with a third party. Your cellular provider, under this interpretation, is a third party with whom you've willingly shared your movements, 24 hours a day, going back months -- even though you don't really have any choice about whether to share with them. So police can request records of where you've been from cell carriers without any judicial oversight. The case before the court, Carpenter v. United States, could change that.
...
Warrants are a security mechanism. They prevent the police from abusing their authority to investigate someone they have no reason to suspect of a crime. They prevent the police from going on "fishing expeditions." They protect our rights and liberties, even as we willingly give up our privacy to the legitimate needs of law enforcement.
The third-party doctrine never made a lot of sense. Just because I share an intimate secret with my spouse, friend, or doctor doesn't mean that I no longer consider it private. It makes even less sense in today's hyper-connected world. It's long past time the Supreme Court recognized that a months'-long history of my movements is private, and my e-mails and other personal data deserve the same protections, whether they're on my laptop or on Google's servers.