Civil wars are a phenomenon with diverse and heterogeneous geographical distribution. The studies about them have multiplied in recent decades, but few have tried to assess its relation with the various institutional settings. As far as it is known, none of them dealt specifically with the high chambers, legislative houses fundamental for the political organization of the countries where they are located, especially those which are in the process of transition (or consolidation) towards democracy. This is the main purpose of the paper: assess the extent to which the high chambers serve as a tool of negotiation between elites, in order to reduce the occurrences of civil wars in the country. The proposal seems to make sense, if we consider the high chambers usually represent the upper classes and the privileged minority interests (UHR, 2008), thus making the change of the status quo more difficult (TSEBELIS; MONEY, 1997). In addition, they tend to be extremely flexible in their composition and operation, they are adapted to many contexts and situations and count with different forms of recruitment of their members (the majority is chosen indirectly). The idea is that they may be easily set up and configured to assist in the negotiation between privileged segments of the population, as well as serving as one more channel available to dictators, authoritarian regimes, to co-opt representatives of the elites.