Do the police need a warrant to download pics/videos from a "found" cell if they download AFTER establishing ownership of cell?

If security guard is not a police officer and school is private, then the fourth amendment does not apply. If public, then a reasonableness test is applied.

This is a key privacy issue. Cell phones have gotten smaller and more capable, and can reveal intimate details of someone's personal life. Few people with mobile phones use encryption which will conceal the contents of communications from police. Under what circumstances cell phones can be searched without a warrant remains an unresolved question in the courts?

One famous court case exists on the issue, United States v. Finley (5th Cir. 2007).

In that Finley case, the police arrested the defendant and a passenger in the defendant's car after a traffic stop. The police seized the defendant's cellular phone at the time of the arrest. They then drove the defendant to the passenger's residence. While at the residence, officers searched the call records and text messages on the defendant's cell phone, and questioned him about those records and messages. Those results were not deemed private by the court and the results were considered "open" and the search was upheld as legal.

Just last month (September 2009) the Ohio Supreme Court took a case to decide the issue. The lower Ohio courts had ruled that the cell phone was like a container and a search of cell phone contents was legal under those particular circumstances.

You need a lawyer to mount a challenge to the search. Check with an in-state lawyer in your locale to discuss more of the details. It's a complex issue that boils down to what a police officer can do "incident to your arrest," meaning without a warrant. So far, it seems most court decisions involving cell phones have allowed police officers to even use forensic devices to extract information without a warrant. Warrantless searches, of course, generally violate the Fourth Amendment. But our Supreme Court has allowed an exception permitting warrantless searches at the time that someone is being arrested. The rationale is safety, i.e. that police should be allowed to look for weapons or items that could be linked to an alleged crime. A second exception to the warrant requirement is a "booking search". That deals with establishing an inventory of the defendant's possessions.

Good luck to you.

God bless.

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