This issue has gotten a bit of press lately, and Ars goes through the details of the actual technology the police might be using on your cell phone.
If a police officer stops you in the course of investigating some matter, can she peruse the contents of your mobile device as she might demand your identification or the contents of the glove compartment of your vehicle? Does a routine traffic stop allow access to your phone’s photos, videos, text messages, and contacts?
The gear to grab this data is widely available. Cell phone extraction hardware made by CelleBrite, for instance, can grab a phone’s contacts database, its text message log, call history, pictures, videos, ringtones, or even a “complete file system memory dump.” The Michigan State Police is a CelleBrite customer, and its routine use is raising questions about the propriety of law enforcement accessing data stored on cell phones.