Complex sentence: Dōshin were samurai but of a lower class than yoriki, they preformed the duties of prison guard and patrol officer which required close contact with commoners (chonin), they investigated crimes such as murder and helped with executions.
Split into simpler sentences: Dōshin were samurai but of a lower class than yoriki--they preformed the duties of prison guard and patrol officer which required close contact with commoners (chonin). They investigated crimes such as murder and helped with executions.