The Shiawase Decision is a 2001 US Supreme Court ruling, part of Nuclear Regulatory Commission v. Shiawase Corporation (2001) lawsuit. The NRC brought this lawsuit against Shiawase for criminal negligence when a terrorist commando was stopped within the containment building of a Shiawase power plant. The Supreme Court considered Shiawase willingness to ensure maximum safety was limited by US laws, and ruled the exemption for foreign corporations of US laws within their property, establishing the principle of corporate extraterritoriality. This ruling should have been applied only to foreign corporations, but the Supreme Court extended it to comparable US corporations to ensure a fair business environment.
The Shiawase Decision is actually based on previous decision, including the US v. Seretech Corporation (1999) (Seretech Decision) which recognized the Seretech right as a moral entity to possess firearms for its own protection, and the usage of firearms through security personnel, and Nuclear Regulatory Commission v. Shiawase Corporation (2000) which authorized Shiawase to install and run a nuclear reactor to supply its facilities, on the basis that the NRC decision could not limit Shiawase's rights to conduct fair business in the US granted by US commercial treaties. In 2001, Shiawase lawyers successfully argued that the applications of a number of US laws within Shiawase property had effectively threatened public security. Most critics consider the Supreme Court could have excluded activities threatening public security from fair business freedom, but was unwilling to overturn its own decisions of the previous few years.
The Shiawase Decision is considered as the most important and famous landmark case in US history, beating by a wide margin Roe v. Wade. Along with the Seretech Decision, the Shiawase Decision is emblematic of the "Ordell Court" presided by Chief Justice Terence Ordell.