When on September 11, 1973, the Chilean armed forces and carabineros, the national police, ousted the properly elected government of Salvador Allende, seized power, and unleashed a violent repression against the Left, they unambiguously broke with standing constitutional norms regarding the obedient and nondeliberative character of the armed forces, valid methods of accession to and abdication of office, the separation of powers, and the rule of law. By these acts the Chilean armed forces put an end to democracy and opened the door to dictatorship. Though the exclusionary and repressive character of the military's rule was blatant from the outset, what type of dictatorship would follow was not immediately evident. Within a day of the coup, the armed forces arrogated to themselves the “Supreme Command of the Nation,” formed a four-man Junta de Gobierno composed of the commanders in chief of the army, navy, and air force and the director general of the national police force, carabineros, and pledged to respect the law and the constitution insofar as the situation permitted.

However, these initial measures were ambiguous and raised a number of questions. First, what would be the scope of the new regime's powers? The concept Supreme Command of the Nation was without referent within the Chilean constitutional tradition and provided few clues as to the range of powers assumed by the military. Second, once the scope of these powers was settled, how would their exercise be organized among the armed forces? Would one force dominate the executive or would mechanisms for power sharing be instituted?