This study is an attempt to contribute to the emerging theoretical literature on state repression. A time-series model was developed to test the hypothesis that state violence in Argentina and Chile is largely a function of four internal political factors and their interactions: 1) the inertial influence of past restrictive policies on the formulation of current policies, 2) the annual incidence of political protest demonstrations, 3) the perceived effectiveness of repressive measures on unrest, 4) and the institutionalization of military rule.