Separation of powers, division of the legislative, executive, and judicial functions of government among separate and independent bodies. Such a separation, it has been argued, limits the possibility of arbitrary excesses by government, since the sanction of all three branches is required for the making, executing, and administering of laws.
Walter Cunningham's jaw muscle twitches because he is ashamed and self conscious about his low income. The teacher is new to Maycomb and is unaware of this economic difference that is present in Maycomb.