Did you at least report the guy who bumped into you to the police? Claiming that you got coerced to cross the light/intersection would be the only thing that could get you some ground here. Even if the guy behind you did a hit and run, you should have reported that anyway to strengthen your case. You must at least have noticed what car he was driving... I find it quite hard to believe that the cop didn't listen to you at all. Around this part of the world, they'll usually take a written account of your testimony. Strange story.
