A federal appeals court on Tuesday upheld the conviction of the Mexican drug lord known as El Chapo.

       Joaquin Guzman sought to overturn his conviction in Brooklyn federal court on ten grounds. The appellate court concluded "none of these claims has merit."

       Among Guzman's arguments, the strict conditions of his confinement before trial inhibited his rights to prepare a defense and benefit from the assistance of counsel.

       MORE: El Chapo sentenced to life in prison

       "The District Court did not err in concluding that Guzman was able to assist in his own defense and receive a fair trial, despite the conditions of his pretrial confinement," the decision from the 2nd US Circuit Court of Appeals said. "The conditions of Guzman's pretrial confinement, harsh as they were, do not provide a basis for disturbing his conviction."

       Henry Romero/Reuters, FILE

       Recaptured drug lord Joaquin "El Chapo" Guzman is escorted by soldiers at the hangar belonging to the office of the Attorney General in Mexico City, Mexico, Jan. 8, 2016.

       Guzman was convicted in 2019 of conducting a continuing criminal enterprise, including large-scale narcotics violations and a murder conspiracy, drug trafficking conspiracies, unlawful use of a firearm, and a money laundering conspiracy. He is currently serving a life sentence.

       MORE: El Chapo's wife sentenced to 3 years in prison

       El Chapo was the leader of the Sinaloa Cartel. Under his leadership, the Sinaloa Cartel imported more than a million kilograms of cocaine and hundreds of kilograms of heroin, marijuana, and methamphetamine into the United States. Trial evidence proved the cartel used murder, kidnapping, torture, bribery of officials, and other illegal methods to control territory throughout Mexico and to subdue opposition.

       In November, Guzman's wife, Emma Coronel Aispuro, was sentenced to 36 months in federal prison for conspiring to distribute cocaine, meth, heroin and marijuana for import into the U.S; money-laundering and helping run the Mexican drug cartel in which her husband was the boss.

       ABC News' Luke Barr contributed to this report.