If they are part of a conspiracy to murder, they are guilty of murder. If they were part of the conspiracy at the beginning, and then did not do a positive action to get out of the conspiracy, they are guilty. The park police officer has a good defense. The three police officers that were in the immediate area assisting Chauvin are legally screwed.
To get it down from murder, you have to prove that choking could not foreseeably cause death. Choking does cause death, so that is a tall order.
you do realize just because someone causes the death of another, it's not always murder 1, right? why do you think we have manslaughter on the books? this is not fantasy world - our laws have actual definitions. murder 1 is intent to kill with lying in wait. no DA could prove that. 2nd could POSSIBLY be proved, but it would be a stretch. manslaughter is negligent homocide. a reasonable jury will believe he did not intend to kill the man but acted recklessly.
and sent him for a pacemaker.