Revealing mistake: When the final race is under way, the silver Saleen S7 hits a Police SUV and makes it flip, you can see the smoke coming out of the bottom of the SUV where the cannon has fired to flip the SUV.
Revealing mistake: When the first race gets underway, if you look at the roadway just before the cars start drifting, you can see the tyre marks of previous takes on the road.
Answer: I agree with Ssiscool though I am not a cop either. This method is way too drastic and risky, I doubt that any police would use such uncontrollable and destructive force to simply stop a suspect while they could just install spike strips or - as suggested by the aforementioned - place a proper road block, giving a chance to the offenders to stop in time and surrender.
Dangar