About an hour ago i was driving up the M5 towards the M6, weather was a bit shit, rain, spray etc. I overtake some cars, pull into middle lane, drive a wee bit further indicate pull out into 3rd lane to overtake – repeat a few times. On pulling out the 3rd time a volvo comes right up behind me and puts his full beam on, so i put on my fog lights to let him see my lights are also working (prikc) Road goes down to two lanes and the nobber tailgating me decides to put on his dash mounted blue flashing light, i pull over where it is safe and he comes running up to my car as i open the door. He says ” Do you think it is smart to be pulling in and out of the lanes in this weather? I should take your licence of you now you fuKKcing idiot and take it back to the office. Now fcck off” he then ran back to his car. Looked a bit scruffy for a cop, cheap nasty shirt and tie. Car was a blue Volvo saloon, with those cheap bluish headlight bulbs in them. Let off for me, or do you think anyone would have the bollocks to pretend to be a cop, bit dodgy trying it on the M5 / M6 Junction.