In the coming months, the U.S. Supreme Court is expected to issue a ruling on whether law enforcement officers have the right to seize your cell phone and comb through it,  without a warrant, if you're stopped for any reason.

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"For many years police have been allowed to seize physical evidence they find on someone they're arresting, or suspect of committing a crime, but now with cell phones it's really not just a piece of physical evidence, it's a physical object that contains a tremendous amount of physical evidence of all sorts," said Stuart Green, a professor of law at Rutgers.

He said privacy concerns are being raised because cell phones frequently contain a lot of personal information.  "Everything we're doing in life, everyone we're communicating with, websites that we visit, the places that we go - we all have private information that we keep, where we go, who we had lunch with, who we're communicating with. It doesn't have to be criminal evidence that people want to keep private, we all have things in our lives that we don't want to share with anyone, and perhaps especially the police."

Green said the U.S. Supreme Court seems to be fairly evenly divided on most issues, and there seems to be a narrow majority that tends to favor the police in most cases involving criminal procedure.  However he said "you can't necessarily count on the Supreme Court always deciding that way."

He said some believe it makes sense to let police seize the cell phone, and then go and get a warrant once they get back to the police station, so they'd be required to show probable cause that the phone has evidence of a crime.

"I don't think it's that much of a handicap for the police," he said. "It's a slight inconvenience of course, but I think it's an inconvenience that's worth protection of people's individual privacy rights."

If the U.S. Supreme Court rules no warrant is needed to check cell phones, Green said it's possible the New Jersey Supreme Court would interpret the state Constitution to require that police get a warrant before they can search a cell phone.