This is a pretty old movie that most people have probably not seen and I can't ask this question without diffuse spoilers, so if that bugs you, watch it first. But strictly speaking, having seen the movie is not necessary to answer the question; I think I can provide relevant details.
The story basically is in 1885 Nevada territory three men are lynched (for a murder based on hearsay, the report of a pretty young man who himself was not an eye-witness) while the sheriff is away. Out of 28 people, 7 stand aside to oppose it and throughout the proceedings people have been suggesting merely waiting for the sheriff or checking out the story of the leader of the trio.
Shortly after the trio are hanged, the sheriff arrives and angrily tells the men, one of whom he had deputized who in turn had illegal deputized the members of the lynch mob (Not every man (and one woman) go on the expedition to catch the "murderers" -- some go out of fear of what might happen if they do not as accusations are flying and some go because not too much is going on in the town which has but one saloon and hotel), the Lord better have mercy on you because I sure won't and he rides off -- he informs them that the man who was shot did not die and they had the men who had done it in custody. He also asks one old man who has been the voice of reason who was responsible, and the old man says, all but 7.
The end is many of the men in that saloon, looking gloomy but apparently free to go. The main agitator for the hangings is a pompous ex-confederate officer (maybe) who killed himself when he returned to town.
My question is, is there any case in which 21 or whatever number people faced charges for a lynching or would it be only those who actually gave the command or directly participated? It was the ex-rebel who gave the command and perhaps that's why he conveniently killed himself.
I guess there is too the lack of witnesses who themselves could show they were innocent.