reckless driving advice wanted

Here in CA, the rear ender is 99% always at fault. There is no excuse hitting someone in front of you if you are paying attention (remember the second for every 10mph following rule from drivers ed?). Even "swoop and brake" collisions (staged?) dont fare well. Good luck, hope it gets dropped. Dont expect anything from the driver who will get a judgement against him and just throw up his hands saying that he has no money, thats usually case closed down here. Get your insurance involved, that is what you pay them to do.