The democratic openness ( 'abertura') in Brazil created optimism with the possibility of the country to solve its problems as chronic inflation and corruption. It was made panacea about democracy; from democracy would emerge the solutions for all national misfortune. However, the recent history shows that democracy did not coincide with the elimination of chronic corruption and inflation. On the contrary, corruption has damaged some fundamental institutions of democracy like the Presidency and the Congress. Unfortunately, corruption is very dangerous to democracy itself. As noted Tocqueville, with his natural perspicacity, people even tolerate corruption in a tyranny, because it is a natural fact in this kind of government. Nevertheless, in a democracy, corruption is unacceptable because common people are elected to represent citizens not to work against them. The last Brazil's corruption scandals, as the Collor case and mainly the 'inadequate' utilization of the national budget were important because they showed the society's incapacity to control this institutional risk factor. It is interesting to note that in other big corruption cases in Latin America, as like as in Gráu's Cuba, Portillo's Mexico or even in Venezuela, during the euphoric 70's, the economic and even political situation were not bad. However, in Brazil the political corruption apparently grew up in a period of structural crises. Unfortunately, this fact has an undesirable outcome: the crescent pessimism of the common man or woman about the future. However, corruption can be studied scientifically. It can be seen as a rational choice behavior constrained by institutions and incentives schemes. Maybe some interesting results could emerge from such a kind of a theoretical and historical speculation about corrupt behavior. This is the main purpose of this paper.