So as I understand this, you were sitting in a cops blind spot, which is dumb but not illegal. He changes lanes into you causing you to crash. He then charges you with an unsafe lane change or some other wrongful movement, possibly to avoid responsibility for not seeing you. Did you get the name of any witnesses to support your story? Without that, or a continuous loop camera, its your word against the cop's, and we all know how that goes. Was SIU called out? Usually if a cop is involved in an accident that involves injury in the performance of his duty, they would be called. If they were, it just means a bigger investigation before they clear him. Best of luck!