The United States Supreme Court has yet to issue a ruling on whether someone accused of a crime can be compelled to provide the passcode to their cell phone.

I believe the 5th Amendment protects cell phone passcodes, and defendents can refuse to provide the passcode to their phone, even if law enforcement has a warrent for the contents of the cell phone.

The Utah Supreme Court has ruled that not providing a passcode should not be held against a criminal defendant, or used against them at trial.

More of this please.