Editing Universal jurisdiction (section)

===United States===
The [[United States]] has no formal statute to authorize it. In some cases, however, the federal government has exercised [[self-help (law)|self-help]] in the apprehension or killing persons who are suspected of conspiring to commit crimes within the United States from outside of the country or committing crimes against American officials outside of the United States. This has occurred even when the suspect is not a United States person, has never been to the United States, and even when the person has never conspired or assisted in the commission of a crime within the United States, there is a functioning government which could try the person for the crime committed there, and notwithstanding the existence of a proper treaty of extradition between that country and the United States, ignoring the provisions of the treaty and capturing or killing the person directly.

In 1985, the [[Mexico|Mexican]] national [[Humberto Álvarez Machaín|Humberto Alvarez-Machain]] allegedly assisted in the torture and murder of a United States [[Drug Enforcement Administration]] (DEA) agent in Mexico. Mexico declined to extradite a Mexican national for the alleged crime committed in Mexico, despite having a treaty of extradition. The United States then hired a private citizen and some Mexican nationals as [[Mercenary|mercenaries]] to kidnap Alvarez-Machain and take him to the United States for trial. The trial court ruled that his arrest was unlawful because it violated the extradition treaty. On appeal, in ''[[United States v. Alvarez-Machain]]'', 504 U.S. 655 (1992), the [[Supreme Court of the United States|Supreme Court]] held that, notwithstanding the existence of an extradition treaty with Mexico, it was still legal for the federal government of the United States to exercise self-help by forcibly abducting him on a street in Mexico and bringing him to the United States to stand trial. In Alvarez-Machain's subsequent criminal trial, he was acquitted; he later lost a [[lawsuit]] against the American government on the grounds of wrongful apprehension and imprisonment.<ref>See ''[[Sosa v. Alvarez-Machain]]''</ref>