Cristiano Zanin Martins (born 15 November 1975) is a Brazilian attorney and professor who serves as justice of the Supreme Federal Court.

[1] He gained notoriety as personal attorney of president Luiz Inácio Lula da Silva in lawsuits related to Operation Car Wash. On 1 June 2023, Zanin was appointed by president Lula da Silva as Justice of the Supreme Federal Court, replacing retired Justice Ricardo Lewandowski.

[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.

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 violent anti-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 the Brasília International Airport, where, in a violent and hostile way, he was filmed while he was insulted and threatened of aggression.

[41] Justice Luís Roberto Barroso affirmed that he couldn't see in an eventual nomination "any ethical, nor moral conflict, nor violation of impersonality".

[42] Justice Cármen Lúcia evaluated that Zanin meets the constitutional requirements of remarkable legal knowledge and unblemished reputation.

[43] Justice Gilmar Mendes stated: "I don't see any obstacle for Zanin's nomination, which I consider a good attorney a many times misunderstood".