You obviously know little about policing. It's a regularly known and used distraction technique for motorists who are believed to have a high risk of driving away (and thus putting officers in close proximity into danger). Admittedly, kicking the windscreen is not part of this technique and I would say was rather silly.
It's obvious that there is more to this story than is reported, so I can't make a judgement to whether it is justified or not.
climbing on the bonnet of a car of someone you believe is going to drive off is a regular technique?
****ing hell surprising more of the tards don't get their brains crushed under a wheel.