Can I sue the Highway Patrol for false accusation of manslaughter, defamation of character, and slander?

I was recently accused of racing a vehicle which wrecked. 2 people inside the car (my two best friends) died and 2 others were seriously injured. I can easily prove my innocence, yet the Highway Patrol has paid no attention to my testimony. They interrogated me at midnight, the night after the accident (after they never tried to contact me during the day) and never informed me that the interview was being recorded. They later told my father that the conversation was videoed; Dad then asked for a copy of the video, only to be told that it had been "lost" (most likely destroyed). I also never acquired a copy of my legal statement. They have released statements to television stations, radio stations, and newspapers claiming that the accident was my fault. One officer even told me to my face that he knew in his heart that the accident was my fault, and that if he were working the wreck, I would have already been apprehended for involuntary manslaughter! This has destroyed my reputation completely, it has killed me emotionally, I constantly have dreams about this terrible situation, and I wish to pursue legal action against the men responsible. Is it possible to win a lawsuit against the Highway Patrol if I have sufficient evidence and a multitude of individual testimonials? Any information would be greatly appreciated!