He taughtcivil law at the Autonomous School of Law (FADISP) in São Paulo.[8]
Zanin is one of the authors of the book "Lawfare: uma introdução", which talks about "the strategic use of Law for political, geopolitical, military and commercial objectives" and founded in 2018 the Lawfare Institute for the production of content about the subject and analysis on real cases.[9]
Zanin began his attorneyship in 2000 as an attorney at the office of Arruda Alvim, where he was an intern during college. In 2004, he became partner of Teixeira Martins Attorneys-at-law.[10][11] In 2022, he opened his own attorney office, in a partnership with his wife Valeska Martins, daughter of his former partner Roberto Teixeira.[12]
He had worked in business lawsuits and judicial recoveries, dedicating in famous cases such asVarig judicial recovery,[b]Transbrasil bankruptcy and the lenience agreement review ofJ&F Investimentos.[13] In the end of January 2023, Zanin was hired byLojas Americanas to work in a lawsuit againstBTG Pactual.[14]
Zanin is also member of the Institute of Brazilian Attorneys (IAB), of the São Paulo Attorneys Association (AASP) and theInternational Bar Association (IAB).
Zanin became the attorney of Lula's family in 2013[15][16] and gained notoriety after becoming his defense attorney in a joint work with criminal attorneysJosé Roberto Batochio and Luiz Felipe Mallmann de Magalhães[17][18] in lawsuits related to investigations ofOperation Car Wash.[19][20]
Cristiano Zanin in a press conference.
In September 2020, in a subphase of Operation Car Wash, judge Marcelo Bretas ordered a search and seizure in houses of attorneys whose offices provided services for Sistema S.[21][22] Among the offices investigated were Zanin's and the office of Frederick Wassef, former attorney ofJair Bolsonaro.[23] Zanin stated that the complaint was a retaliation to his work as defense attorney of president Lula and added that "this is the goal of Car Wash. Remove me or reduce my time in the defense of president Lula and in other cases I work in. But this is not going to happen."[15] Zanin also pointed out the fact that Bretas had sympathy for president Bolsonaro.[24] TheOrder of Attorneys of Brazil (OAB) saw the operation as "a clear inititiave of criminalization of Brazilian attorneyship".[25] The complaint was later archived.[26]
In 2021, ahabeas corpus request filed in theSupreme Federal Court by Lula's attorneys resulted in the repeal of Lula's convictions related to Operation Car Wash, as the court acknowledged the partiality of Sergio Moro, declaring him suspect and repealing his rulings.[28] Consequently, the political rights of Lula were restored, allowing his candidacy in the2022 elections, which he was elected President of Brazil for the third time.[29]
Zanin participated in the coordination of thepresidential campaign of Luiz Inácio Lula da Silva in the 2022 elections.[26]
In November 2022, he was designated to compose a technical group on Justice and Public Security in thepresidential transition cabinet. Zanin was responsible for the report of International Judiciary Cooperation and National Strategy of Fight against Corruption and Money Laundering (ENCCLA).
On 11 January 2023, during the aftermath of severe and violentanti-democratic events against the Three Powers building in Brasília perpetrated by terrorists who supported former president Jair Bolsonaro, Zanin was approached by Bolsonaro supporters in the restroom of theBrasília International Airport, where, in a violent and hostile way, he was filmed while he was insulted and threatened of aggression.[30] In the video, the offenders affirmed that he should be assaulted for being part of Lula's defense.[31] Zanin remained calm and regretted what happened, as well as he hoped the persons responsible for the attack would be punished.[32] The man responsible for the recording, a 29-year-old entrepreneur,[26] was identified and indicted for threatening, injury and crime incitement.[33]
After the election of Lula for president, Zanin was considered for Justice of the Supreme Federal Court.[34][35][36]
For the fact he had acted as personal attorney of the president, his possible nomination was heavily criticized, both from the opposition and from personal allies and supporters of Lula administration.[37][38][39]
On the other hand, Zanin received support of attorneys,[40] the President of the SenateRodrigo Pacheco and from justices of the Supreme Court.[41] JusticeLuís Roberto Barroso affirmed that he couldn't see in an eventual nomination "any ethical, nor moral conflict, nor violation of impersonality".[42] JusticeCármen Lúcia evaluated that Zanin meets the constitutional requirements of remarkable legal knowledge and unblemished reputation.[43] JusticeGilmar Mendes stated: "I don't see any obstacle for Zanin's nomination, which I consider a good attorney a many times misunderstood".[44]
On 21 June 2023, Zanin had a public hearing in the Federal Senate, with his nomination approved on the same day at the Constitution and Justice Committee in a voting of 21–5 and by the floor in a voting of 58–18.[48]