SAO PAULO -- Brazil's top court said Thursday it would soon rule on President Dilma Rousseff's motion to annul the upcoming impeachment vote against her, a process that the top legal official in her government said had been "contaminated."
Justices will also rule whether voting procedures established by Speaker Eduardo Cunha, Rousseff's sworn enemy, are valid or not.
Supreme Court justices had not been expected to rule on Thursday. However, Ricardo Lewandowski, the chief justice, said that "exceptional situations require exceptional measures." Justices will begin debating at 5:30 p.m. local time and the process could go late into the night.
The extraordinary meeting of justices is the latest development amid weeks of legal wrangling over a process in Congress that has exposed deep divisions in Latin America's largest country.
The lower house is slated to vote Sunday on whether to impeach Rousseff for breaking fiscal rules. But if the Supreme Court decides to annul the latest procedures the case could go several steps back.
Earlier Thursday, Solicitor General Jose Eduardo Cardozo filed the annulment motion to the court. He argued that Cunha had presented the impeachment push in such a way that went beyond the actual accusations against Rousseff.
Cardozo made the same claim about the report submitted to the special committee, which voted on Monday to send the measure to the full body. He said discussion included the overall political crisis, the recession and a sprawling corruption probe at state oil company Petrobras.
"We are not talking about the merits of impeachment" but rather the process, Cardozo told reporters in Brasilia.
Political observers interpret the government's moves as a last-minute final effort to avoid a first major defeat in the process. The pro-impeachment camp needs two-thirds of the 513 votes in the lower house, or 342 votes, to send the proceedings to the Senate for a possible trial. If the Senate takes it up, Rousseff would be forced to step down until the measure is voted on.
Both government and opposition forces say they have enough votes to win on Sunday, but daily counts by Brazilian media suggest that the opposition is much closer to victory.
