LMB, Here's an excerpt from the TSG training manual
"Should an officer in full riot gear meet a pedestrian shuffling along with his hands in his pockets, with his back to the officer, the officer should;- Place a scarf over his own face to conceal his identity. Remove any external badges which may later identify him.(unless he has already done so). Approach the intended victim/pedestrian, with his baton fully extended behind him and strike heavily on the legs/back of the aforementioned victim/pedestrian, before shoving the victim/pedestrian heavily to the ground. No warning should be given to the victim/pedestrian before commencement of this action. TSG officers should be aware however that the media/passersby may have in their possession, video/digital cameras and therefore should try and position themselves in such a place as to be obscured from the view of these people..
Officers are further reminded that should the victim/pedestrian later die, the Met will use a pathologist of dubious integrity to ensure the victim/pedestrian, died of natural causes."
You couldn't make it up.