Mario Ernesto Villanueva Madrid, sometimes known as "El Chueco",[1] (born 2 July 1948) is a Mexican politician who built an important political career within the ranks of the Partido Revolucionario Institucional (PRI).

Accused of drug trafficking at the end of his gubernatorial period, he did not arrive at the ceremony at which he was to hand the office over to his elected successor, Joaquín Hendricks Díaz, and remained a fugitive from justice for two years.

[6] After a lengthy process that included the lodging of amparo constitutional relief remedies, the extradition request was granted by the Secretariat of Foreign Affairs on 7 November 2007.

[2] On 29 June 2013, Villanueva was sentenced in New York, United States, to 11 years in prison after being accused of conspiring to import hundreds of tons of cocaine and launder millions of dollars in bribe payments.

[9] Starting in 2018, Villanueva was held prisoner in Chetumal, but on 24 December 2019, President Andrés Manuel López Obrador spoke about a pardon by the end of the year.