Extraterritorial operation

An extraterritorial operation in international law is a law enforcement or military operation conducted outside the territory or jurisdiction of the state of the forces in operation, generally within the territory of another sovereign state. Under international law, these activities are generally highly restricted, and it is considered a violation of a state's sovereignty if any other state engages in law enforcement or military operations within another state without gaining that state's consent:

The policing of transnational and international crimes is a challenge to state-based law enforcement agencies, as jurisdiction restricts the direct intervention a state's agencies can legally take in another state's jurisdiction, with even basic law enforcement activities such as arrest and detention "tantamount to abduction" when carried out extraterritorially. These explicit limits on extraterritorial law enforcement operations has therefore instead encouraged co-operation between law enforcement agencies of sovereign states, forming supranational agencies such as Interpol to encourage co-operation, and placing additional obligations on the state such as aut dedere aut judicare ("extradite or prosecute") to compel prosecution of certain types of transnational crime, including hijacking of civilian aircraft, taking of civilian hostages, and other acts of terrorism, as well as crimes against diplomats and other "internationally protected persons".

While extraterritorial law enforcement activity is highly restricted and subject to the approval of the 'host' state, traditional interstate military operations assume some degree of extraterritorial operation. As Stigall points out, innate in 'just' war (jus ad bellum) is the expectation that one state may be conducting military activity against, and within the borders, of another state; the laws of armed conflict "[presuppose] extraterritoriality". Therefore, "[i]f the circumstances exist for the lawful use of force under jus ad bellum, then so long as a state abides by the rules articulated in jus in bello [the law of war], that state’s extraterritorial actions are considered lawful."

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