Wendy McElroy over at Gizmodo has an article up about a ongoing trend in law enforcement and legislative action,

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.

Yep, can’t have any evidence that contradicts the officer’s story of events.  That would be bad.  Then people might start to question the honesty and integrity of their keepers.