Mitch, I've got to agree with John, buy some new tyres and get it past the pits. I've been stickered 7 times, so I understand what a pain it is, but having bald tyres is crazy especially in the wet.
If the put the sticker in the middle of your window then I would make a complaint against the police, so sticker is allowed on the middle of the windscreen as it can obscure your vision.
Cheers
Paul