To identify a bank robber, prosecutors in Connecticut obtained records for 169 phones in 2009 without a search warrant.

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In California and other states, police can legally search phones even without a warrant, though courts around the country are still producing conflicting rulings on the issue.

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In a landmark case in December, the U.S. Court of Appeals for the Sixth Circuit ruled that the government violated the Fourth Amendment when it obtained 27, 000 emails without a search warrant.

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Magistrate Smith said he was puzzled by cellphone-tracking requests when he was new to the bench: he couldn't find a provision in the law allowing police to track a phone for as long as 60 days without a search warrant.

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The embassy says the police raid was carried out without a proper search warrant and that no evidence against Mr Saboor was found.

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This case and a separate and still pending appeal over police intrusions into homes and cars could have a far-reaching impact on when a person's private contents can be subjected to a search without clear probable cause or a valid warrant.

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Thus, the police can serve the ISP providers with a search warrant and get the information turned over without notifying an e-mail account holder.

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Diaz (holding that a police officer can search the contents of a cellphone after a lawful arrest without a warrant).

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Police were free to employ the tactic for any reason without showing probable cause to a magistrate and getting a search warrant, the government said.

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