Operation Car Wash began in March 2014 and went on to become the largest operation against corruption in Brazil's history. It brought to light the fact that Petrobras, that at one point was the fifth most valuable company in the world, had been bled for many years at the hands of criminals. Since the scheme was funding politicians and parties, it is possible to say that this was not just a corruption scandal, but also a real attack on democracy, promoted by parties in power and in the opposition, both in the current government and the previous ones. At first glance, Brazil's Criminal Justice system seems to be undergoing a drastic change with Car Wash. A senator in office was arrested in precautionary custody. Dozens of business owners and executives at the highest levels were also taken into custody and continue being the targets of investigations and criminal proceedings. Finally, it appears that justice became effective for everyone. However, despite the evolution of anti-corruption promoted by Car Wash, the operation is target of severe criticism. Many believe it disrespects civil principles of criminal procedure, leaving fundamental rights in the background. The dubiousness of opinions in relation to the operation, coupled with the political scenario of struggle for power, resulted in Car Wash being politically appropriated by two different narratives. In one, it is propagated that the Workers' Party (PT) is responsible for the corruption in Brazil and that it would be enough to remove the party from power to resume the path of economic growth. In another, the operation is accused of being selective, directing investigations at crimes involving the Workers' Party (PT) as a way of taking over power through a coup and removing former president Lula from the political scenario. In this context, Lula was charged in the Operation. Paradoxically, the investigations may, however unwittingly, have favored him, who went on to articulate the facts in his favor and capitalize on popular support, sharply reducing his rejection levels, rising in the opinion polls and presenting himself as the strongest candidate for the presidency in 2018. The huge amount of detail in the midst of countless legal controversies generated a series of questions, for example: - Is there any legal reason why Car Wash is only investigating corruption during the government of the Workers' Party (PT)? - Could there be a connection between precautionary custody and plea bargains? - Although people say Dilma Roussef's impeachment was a coup, could it somehow have benefited the Worker's Party (PT)? - Was the bench warrant deposition of Lula legal? Was Judge Moro allowed to release the wiretap recordings of Lula? - Who is actually affected by the Supreme Court's (STF) decision that the sentence should be enforced after a conviction is upheld by a Court of Appeals? - Could Car Wash, even involuntarily, have contributed to former president Lula becoming favorite in polls for the presidential election of 2018? These and other questions will be answered here. To facilitate the understanding of the operation, each chapter corresponds to the respective stage of the police investigation and the main legal issues related to each stage will be presented in a simple and straightforward way, at the end of each chapter. In matters involving controversial discussions, legal arguments for and against them will be presented in an impartial, pluralistic and non-partisan manner, at least as far as possible in such a polarized country, so that readers can come to their own conclusions. It is not, therefore, a scientific study of each legal subject, since, due to the complexity of the issues, it would be contrary to the main objective of this book: to synthesize Operation Car Wash, clarifying its main legal controversies and contributing to everyone's informed views on the power struggles in the Brazilian democracy.