SÃO PAULO — Brazil's presidential system, first installed in 1975 by Brazil's post-dictatorship New Republic, has failed. The recent conviction of Lula da Silva, the former president, who's now aiming to run to return to the top job in 2018, only provides more evidence to support this fact.

Over the past 30 years, virtually every president has eventually run into trouble with the justice system. The only ones who can sleep without a worry are Fernando Henrique Cardoso (1995-2002) and José Sarney (1985-1990), who were spared because of advanced age and because they were lucky enough to have governed the country at a time when the on-duty "shelvers" of the Republic (as a famous former general prosecutor, Geraldo Brindeiro, was nicknamed) were still in the capacity to offer protection.

The decay that the political system has produced didn't affect just elected presidents but also their top opponents (José Serra in 2002, Geraldo Alckmin in 2006, Aécio Neves in 2014), as well as numerous governors and almost one-third of the members of Congress.

This occurred because the New Republic invented a perverse formula to manage the relations between the executive and the legislative powers. In our system, the president doesn't have a parliamentary majority. In order to govern, he or she needs an "allied base" of members of both chambers of the legislature who, in turn, support the president in exchange for chunks of the budget and appointments to public offices where opportunities for juicy business are rife.

Because it's a dirty game, the president himself gets stuck in the mud.

Nothing in this system guarantees that the relations between the executive and the legislative will focus on the common good, such as providing decent hospitals, good schools and efficient public transport. On the contrary, the rules of Brazil's presidential game actually mean that the whole society has to surrender its authority in the face of groups of interests that are strong enough to take advantage of the president's necessity to secure support from his base.

Merely the go-to guy

Who wins in such a system? The cartel of construction companies such as Odebrecht, groups of businessmen and entrepreneurs such as Joesley Batista (who recently incriminated President Michel Temer), unionists who take a payment to bring strikes to an end and the lobby of health insurance companies.

In this system, the president's Planalto palace is merely the clearing house of private interests. It is where positions of trust are distributed for top dollar. And it's from there that the traps are laid to influence the justice system and to limit the damage caused by the watchdog institutions.

Right to left Michel Temer, Dilma Rousseff, Lula da Silva and his wife Marisa Letícia — Photo: Wilson Dias/ABr

As the holder of the pen that authorizes it all, the president becomes the collector-in-chief for his allies' campaigns: He's the go-to guy.

Because it's a dirty game, the president himself gets stuck in the mud. These past 30 years have seen our heads of state go crazy with all sorts of bribes, apartments, country houses, renovation works for their mothers-in-law, jobs for their kids, pocket money for their brothers, briefcases full of money and hair cuts from renowned hairdressers.

The bottom line is that more than any man or woman, it is Brazil's very institutions that are dragging the country into the dirt.

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