Wow - this sounds like a crazy law...Are Cameras the New Guns?http://gizmodo.com/5553765/are-cameras-the-new-guns
On March 5, 24-year-old Anthony John Graber III's motorcycle was pulled over for speeding. He is currently facing criminal charges for a video he recorded on his helmet-mounted camera during the traffic stop.
Wendy McElroy — In response to a flood of Facebook and YouTube videos that depict police abuse, a new trend in law enforcement is gaining popularity. In at least three states, it is now illegal to record any on-duty police officer.
Even if the encounter involves you and may be necessary to your defense, and even if the recording is on a public street where no expectation of privacy exists.
The legal justification for arresting the "shooter" rests on existing wiretapping or eavesdropping laws, with statutes against obstructing law enforcement sometimes cited. Illinois, Massachusetts, and Maryland are among the 12 states in which all parties must consent for a recording to be legal unless, as with TV news crews, it is obvious to all that recording is underway. Since the police do not consent, the camera-wielder can be arrested. Most all-party-consent states also include an exception for recording in public places where "no expectation of privacy exists" (Illinois does not) but in practice this exception is not being recognized.
More here: http://gizmodo.com/5553765/are-cameras-the-new-guns