The Supreme Court of Justice of the Nation (SCJN) in Mexico clarified that consular assistance in criminal cases is exclusively available to Mexicans arrested abroad, a decision that arose from a legal amparo filed by José de Jesús María Vázquez Balandra, a man convicted of murder in the United States. Vázquez Balandra had fled to Mexico after killing another Mexican in Los Angeles and was subsequently jailed in Jalisco for 30 years after being tried for his crime.

During his trial, he attempted to overturn his conviction by challenging the admissibility of testimonies from three Mexican nationals who had testified against him in the U.S. He argued that their testimonies should be discarded because they were not collected with the assistance of a consulate, claiming that this violated his rights under the Vienna Convention on Consular Relations. The court deliberated on this matter based on international legal standards governing consular protection and witness rights in criminal proceedings.

The ruling highlights a significant limitation in the scope of consular services and raises questions about the rights of witnesses in international legal contexts. It underscores the need for Mexican nationals abroad to be aware of the legal protections available to them and the implications for how justice is administered across borders, particularly regarding the testimony of foreign witnesses in criminal trials.