Brazil's top court OKs investigation into dozens of top politicians in Petrobras graft scandal

A metallurgical union worker stands outside the state-run oil company Petrobras during a protest for better labor conditions and against layoffs, in Rio de Janeiro, Brazil, Wednesday, March 4, 2015. The company has been engulfed in an ever-sprawling corruption scandal, a kickback scheme that prosecutors say is the largest ever uncovered in Brazil. (AP Photo/Leo Correa) (The Associated Press)

Riot police officers stand guard during a protest of metallurgical union workers demanding better labor conditions and against layoffs at the state-run oil company Petrobras, in Rio de Janeiro, Brazil, Wednesday, March 4, 2015. The company has been engulfed in an ever-sprawling corruption scandal, a kickback scheme that prosecutors say is the largest ever uncovered in Brazil. (AP Photo/Leo Correa) (The Associated Press)

FILE - In this July 8, 2011 file photo, Fernando Collor de Mello, Brazilian former president and current senator, speaks during an interview in Brasilia, Brazil. Brazil's Supreme Court has given the green light for the attorney general to begin investigating dozens of top politicians for alleged connections to a big kickback scheme at state-run oil company Petrobras. Among those the court says will be investigated are Collor, who was forced from the presidency by a corruption scandal in 1992. (AP Photo/Eraldo Peres, File) (The Associated Press)

Brazil's Supreme Court has given the green light for the attorney general to begin investigating dozens of top politicians for alleged connections to a big kickback scheme at state-run oil company Petrobras.

Among those the court says will be investigated are former president and current senator Fernando Collor, who was forced from the presidency by a corruption scandal in 1992.

Also on the list are the current leaders of Brazil's senate and lower house. In total, 54 people are to be investigated.

Federal prosecutors say they've uncovered the largest corruption scheme ever in Brazil. They say that for over a decade, Brazil's biggest construction and engineering firms paid at least $800 million to former Petrobras executives and others in exchange for inflated contracts.