Opinions on this footage caught by an umarked police bike. Was the officer chasing or encouraging the rider to ride fast? In both cases there was recklessness on both sides including an almost head on with another biker.It's not clear whether the officer had his lights or siren on but from the reflections on passed vehicles and ambient sound it would appear not!

http://www.youtube.com/watch?v=W2PBMGmUjTE