Stranded car in lane three, M5 N/B J 12 to 14

Yesterday the radio bulletin announced the car, an unmarked black Bmw had the sirens on and blue lights flashing.
At the rear of the Police car, the sign said keep left with an arrow pointing left.
About half a mile of traffic behind the Police car decided to stay in lane three and follow it, taking no notice of the instructions.
When I went past the car that was broken down, a young lady had it on the grass verge by the central barrier and lane three was not blocked.

Police car.

Lower your expectations in future.