Allegedly according to members from the opposition, cabinet chief Dilma Rousseff pressed the Brazilian Revenue Office in favor of the Sarney family, particularly his son Fernando Sarney, an influential businessman who owns an affiliate of the Globo television network and is also Vice-president of Brazil's football confederation.
Sarney Sr, who is president of the Upper House, faced a battery of charges ranging from nepotism and corruption to influence peddling and misuse of funds, but the case was finally shelved by the Senate Ethics Council headed by one of his close ally from the same party.
Fernando Sarney has been indicted for money laundering and corruption.
According to the opposition, Ms Rousseff recommended the former head of the Revenue office to shelve the investigation on Fernando Sarney
Daily newspaper O Estado de S. Paulo quotes several congressional members of the opposition describing Rousseff's lobbying in favor of the Sarney family as "extremely serious."
The situation is also particularly damaging for President Lula's political plans for next year when presidential elections are scheduled.
Lula is working on an alliance between his Workers Party and Sarney's PMDB (Brazilian Democratic Movement Party), which would support Ms Rousseff as his hand picked candidate for president in October 2010.
Furthermore Lula has instructed ministers and Workers Party congress members to support Senate president Sarney in spite of the fact his ousting has been repeatedly demanded by all parties from the opposition, and according to polls by public opinion.
The Rousseff case opens a new front in the Senate for Lula's coalition and 2010 plans.
The most serious opposition presidential candidate, São Paulo governor José Serra, from the Social Democrats, who lost to Lula da Silva in 2002, is comfortably leading in the polls.
Mercopress