We explore how institutional set-ups, in particular changes in political institutions through coups d'état , can affect the way military expenditures are determined.We use a counterfactual approach, the synthetic control method, and compare the evolution of the military burden for 40 countries affected by coups with the evolution of a synthetic counterfactual that replicates the initial conditions and the potential outcomes of the countries of interest before exposure to coups. Our case studies suggest that successful coups result in a large increase in the military burden.However, when no effects or a decrease in the defense burden are found, it is often the consequence of a democratization process triggered by the coup. These results are in keeping with recent theoretical developments on the bargaining power of the military in authoritarian regimes. Failed coups, by contrast, produce a smaller, and mostly positive, effect on the military burden, possibly as a result of the incumbent's strategy to avert further challenges to the stability of the regime by buying off the military.JEL classification: H11, H56