SAO PAULO, Rajab 08, 1437, April 15, 2016, SPA -- Brazil's top court met Thursday night in an extraordinary session to consider a motion by President Dilma Rousseff to block an upcoming impeachment vote against her, a process that the top legal official in her government blasted as "contaminated," according to AP. Justices began their session discussing whether procedures established for Sunday's impeachment vote by Speaker Eduardo Cunha, Rousseff's sworn enemy, were valid. Initially, Cunha organized the vote for legislators from the industrial and rich south, where the opposition is strongest, to go first. While the justices were meeting, Cunha's lawyer presented a different plan that would alternate between the south and the north, where Rousseff has more support. Supreme Court justices had not been expected to rule on Thursday, but then Ricardo Lewandowski, the chief justice, said that "exceptional situations require exceptional measures." The session was expected to last well through the night. --SPA 03:59 LOCAL TIME 00:59 GMT www.spa.gov.sa/w