A Police car pulled alongside a speeding car

A Police car pulled alongside a speeding car on the motorway. Glancing at the car he was astonished to see that the blond behind the wheel was knitting! Realizing that she was oblivious to his flashing lights and siren, the cop rolled down his window and shouted "Pullover!". The blonde rolled down her window and yelled back "No, it's a scarf!".