In twenty years of crisis and transition，called Second Republic，Italy has changed the electoral laws to determine how votes are translated into seats，from the proportional passing to the majority and finally to the mixed system. The political system has responded to a long crisis of legitimization with five electoral laws，two of which fell due to defects of constitutionality，with two referendums around great constitutional reforms rejected by the people and failed attempts to institutional revision launched with the bicameral commissions. The importance of the electoral system as an independent variable that，with majority or a premium，can produce safe effects in governability has been emphasized by an ideology that with the majority，either in a plurality single ballot system or a mixed system，the vote does not serve to seek a parliament that reflects the voting distributions of the citizens’ orientations but to indicate the clear winner. The governability sought with awards to the winning coalition has not，however，stabilized a democracy that presents itself with a high fragmentation of the party system，an exceptional turnover in the membership of parliament. Without the structural consolidation of a party system，the crisis of the political establishment has produced a tripolar political system that cannot be manipulated with other electoral engineering tests imposed by the majority elite that seeks the distortion of the vote （under-representation of minorities and over-representation of the strongest） in the practice aimed at sacrificing the parliament’s representativeness for the need for efficient government.