Anybody know how to spell...L I E D E T E C T O R?
Give all the "witnesses" lie detector tests. You can bet your azz the cop will take one.
"Oh, no...you be violatin mah cibil rights". No, we are trying to find out if you are a lying rat or not.
I doubt his lawyer would allow it, and in any case you could hook everyone up to lie detectors and it won't make any difference. Lie detectors can be beaten pretty easily, which is why they aren't admissible as evidence in any court.
Right now we have two people who know what happened and one of them is dead. You have a whole bunch of people on both sides trying to prove that their guy was the innocent party. There is no way we will ever know the whole truth of the matter.