The Texas Senate approved legislation Tuesday banning the release of police officers' photos in most cases, a bill open government advocates opposed.

House Bill 2006, by Rep. Dennis Bonnen, R-Angleton, next heads to Gov. Rick Perry.

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The identities of uncover officers should be protected.
However I suspect the the real purpose is to put an end to the growing trend of private citizens using cell phone cameras to document abuse and/or illegal activity committed by law enforcement officers (state, local, federal) as it happens. In court the testimony of a uniformed officer is often given more credence than the contradictory testimony of a civilian. However photographic evidence (possibly from multiple witnesses) can be very difficult to rebut.