Brazil's political crisis explained

Brazil's beleaguered president Dilma Rousseff. Credit: Reuters

Brazil's embattled president Dilma Rousseff will find out on Sunday whether she will face impeachment - the latest development in a political crisis which has gripped the country, with a multi-billion dollar corruption scandal sparking massive protests against the government.

Dilma Rousseff's political future hangs on Sunday's congressional vote. Credit: Reuters

  • What is the background to Brazil's corruption scandal?

Between about 2004 and 2014, Brazil's state-run energy firm Petrobras was involved in a $5.3 billion (£3.7bn) corruption scheme - one of the largest ever to be uncovered.

Construction executives created a cartel to fix bids on Petrobras contracts and overcharge the company. Profits made from this scheme were sent to Petrobras workers and some politicians as bribes.

Demonstrators outside Petrobras' Rio de Janeiro headquarters. Credit: Reuters

  • Why is Dilma Rousseff facing impeachment?

There is no evidence that Ms Rousseff was directly involved in the corruption herself, but she was chairwoman of Petrobras' board from 2003 to 2010, so the corruption happened under her watch.

She has also been accused of window dressing the government's books to hide the extent of the Brazil's deficit problem so she could be re-elected.

Ms Rousseff has denied any wrongdoing and has repeatedly rejected calls to resign, saying the impeachment proceedings amounts to a "coup".

A man waves a flag during protests against Dilma Rousseff. Credit: Reuters

  • Why are people so angry?

Ms Rousseff is the protégé of Brazil's hugely popular former president Luiz Inacio Lula da Silva.

Both are from the leftist Workers Party, which has positioned itself as an honest political group that supports the causes of ordinary working class people.

The party's perceived association with elite corruption has alienated many, and millions of people have taken to the streets to demand Ms Rousseff's resignation.

Crowds protest against Brazil's President Dilma Rousseff. Credit: Reuters

  • What happens if the lower house votes for impeachment?

If two-thirds of members agree that Ms Rousseff should be impeached, the case will be sent to the senate for trial.

However, she can appeal to the Supreme Court. In this situation, the senate would have to wait for the court's ruling before it votes on whether to accept the lower house's recommendation.

If a simple majority of the 81-member senate supports impeachment, Ms Rousseff would have to step down during the trial and Vice President Michel Temer would take her place.

If she is convicted, Ms Rousseff can appeal twice.