In the broadest answer as to whether the police need a warrant to search your cell phone in California, the answer is yes, they need a warrant unless you give your consent. Technically, the police cannot even look at the screen without a warrant, even if they press the button to turn it off.

Cell phones are a major part of our everyday lives now. We have text messages, GPS data, emails, and phone calls on there. Many people keep sensitive information entrusted on their phones. People are very private about their cell phones, even if there is no passcode to unlock it. People often do not want others looking over their shoulder, nor do they want to be that person just peeking over at the person next to them. It is a common-courtesy privacy thing, really.

So call it a major win for well, eve...