FBI taps cell phone mic as eavesdropping tool | CNET News.com
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update The FBI appears to have begun using a novel form of electronic surveillance in criminal investigations: remotely activating a mobile phone’s microphone and using it to eavesdrop on nearby conversations.

The technique is called a “roving bug,” and was approved by top U.S. Department of Justice officials for use against members of a New York organized crime family who were wary of conventional surveillance techniques such as tailing a suspect or wiretapping him.