Firstly, i wouldn't call the police, this happened to my brother and quite litterally within the space of 15 minutes he had 20 lads in cars vans and bikes chasing him.
He was boxed in, dragged out of the car, given a Very good.... Lesson and left their.
the gti he stole was Never a match for the gloria, 300zx and hyabusa chasing him heck, even the glanza woulda caught him, tho i don't condone or endorse speeding, criminal activity or anything of the sort... you have to remember, the fastest cars in the police force here ( gs300's here maybe the xc90's ) that could keep up or catch it wont bother so we done what had to be done... Car thief fell a good 100+ % percent locally.
Further more, if it where my car, Believe me, Cement shoes would be the least of the robbers worrys.
Damn im retro but hey, thats life.
What would happen if you go the legal route: police thank you for keeping your distance - take over, chase and he wreaks the car.
he's nicked, out on bail and disappears, off to commit more crime.
if your done by the speed camera - pay the fine... or say your wife was driving