Complex sentence: His reconstruction of the trajectories of the shots that struck Kennedy and Governor Connally supported the single-bullet theory, claiming that the impossible trajectory suggested by the Warren Commission was only necessary because there was an error in their positioning of Connally.
Split into simpler sentences: His reconstruction of the trajectories of the shots that struck Kennedy and Governor Connally supported the single-bullet theory. Donahue decided that the impossible trajectory suggested by the Warren Commission was only necessary because there was an error in their positioning of Connally.