Cop that!

I know traffic police have a place in our world but I'm just not quite sure where!
I was driving along the M5 at the weekend and saw thousands of tail-lights ahead of me - now that either spells crash or cop. On this occasion, it was the latter. As cars hammered on their brakes in front of me there was almost three pile-ups. Drivers veered from that “naughty” outside lane to the inside so the officer wouldn't spot them and all common sense and driving skills seemed to go wandering.
Admittedly, the traffic stayed at a sensible 70mph as the officer toyed with his followers - speeding up to 73mph and then slowing down again… more tail-lights.
The ironic thing was that after the traffic cop turned off the motorway, a Beamer went hammering passed me in the outside lane and must have been pushing the ton-up. By which time, the police were nowhere to be seen.