Complex sentence: Of the 20 subpoenaed by the prosecution to bear witness to the peaceful nature of the protest, only six appeared to testify, and three admitted to seeing violence committed by the mob prior to the shooting.
Split into simpler sentences: Of the 20 subpoenaed by the prosecution to bear witness to the peaceful nature of the protest, only six appeared to testify. Three admitted to seeing violence committed by the mob prior to the shooting.