In the sentence: ''For the past three years, Brazil has been...

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Brazil corruption scandals: All you need to know

For the past three years, Brazil has been gripped by a scandal which started with a state-owned oil company and grew to encapsulate people at the very top of business - and even presidents.

On the face of it, it is a straightforward corruption scandal - albeit one involving millions of dollars in kickbacks and more than 80 politicians and members of the business elite.

But as the tentacles of the investigation dubbed Operation Car Wash fanned out, other scandals emerged.

It has led to some of those who have found themselves accused claiming they are the victims of political plots, designed to bar them from office.

What is Operation Car Wash?

Operation Car Wash began in March 2014 as an investigation into allegations that Brazil's biggest construction firms overcharged state-oil company Petrobras for building contracts.

Investigators accused directors at the firm - named the world's most ethical oil and gas company in 2008 - of skimming the extra money off the top as a bribe for awarding the contract.

Which is bad enough - but then the Workers' Party found itself dragged into the corruption scandal amid allegations of having funneled some of these funds to pay off politicians and buy their votes and help with political campaigns.

Among those accused in the scandal were dozens of politicians, and Luiz Inacio Lula da Silva - the country's extremely popular former president, known affectionately as "Lula".