Vicente Antonio Bermudez Zacarias, a district court judge in southern Mexico, was shot in the head and passed away en route to the hospital.
Luis María Aguilar Morales, president of Mexico's Supreme Court, released a statement confirming Bermudez's death.
"We have already been in contact with the competent authorities to immediately investigate this case and have it resolved," Morales said, according to Aristegui Noticias. "Federal judges are people who devote their lives, their personal integrity, moral and physical, to administering federal justice and are required to have the security and tranquility that their independence guarantees."
Bermudez handled the legal challenges from El Chapo's lawyers and also handled legal challenges from lawyers working for Miguel Trevino, who had ties to the Zetas cartel.
Authorities have not released a motive for his death.