Tricky question

If a police officer is caught on camera committing a violent criminal act and there is sufficient publicity he apparently gets suspended. Now, if you or I had committed the same violent criminal act in front of a bunch of cops we'd be arrested on the spot. So what were the dozens of cops, including senior officers, who were eyewitnesses of the criminal assault doing? Why haven't the whole bloody lot of them been suspended for dereliction of duty?

OK I know the answer. They were just obeying orders. Heard that one before?