They are getting embarrased by the numbers of clips making it to youtube showing them to be, at best, incompetent idiots and, at worst, complete thugs.
What is marvellous about the CCTV system we have here is that, 9 times out of 10 when you view it there is nothing on it that is useful to the prosecution case, and every time a defendant asks for it to prove his defence, the camera is mysteriously pointing the other way, or else they have not managed to seize the recording before it got recorded over again.