Martin,I'm giving you the point of view from the law's perspective so that you can prepare for court. A cop generally (in most cases) cannot cite an infraction that did not happen in his presence. In the case of a misdemeanor that did not happen in his presence, the witness (in this case the driver) can press charges (PC 836), which is what appeared to have happened. So basically, the driver committed an infraction, but you committed a misdemeanor IF you intentionally broke is window. That other cyclist you passed could be a friendly witness for you if you can find him.