Are you obligated to give your cellphone to a cop upon request?

In this video, San Diego criminal defense lawyer Ryan Tegnelia responds to an online question regarding cellphones and police access. In the same ways police officer footage of an arrest (perhaps a dashcam or bodycam) is considered evidence, any user-filmed video is treated just the same. If the police see you filming an alleged crime or arrest, they may demand to confiscate your cellphone as evidence. If their demands extend to require your password, Mr. Tegnelia explains how you can refuse to provide such personal information. Possession of a video is not enough to eliminate the level of personal privacy extended to your phone.