State immunity comprises:
- immunity from jurisdiction, which allows a state to avoid prosecution in a foreign court;
- immunity from execution, which allows a state to prevent enforcement measures against its assets and property.
The Swiss Federal Supreme Court developed its jurisprudence based on a narrow interpretation of state immunity. Under this interpretation, state immunity is not absolute. The Federal Supreme Court has clarified the conditions under which a foreign state can be summoned before a Swiss court (immunity from jurisdiction). It has also clarified when Switzerland is entitled to take compulsory measures against a foreign state (immunity from execution).
With regard to immunity from jurisdiction, the Federal Supreme Court has adopted the distinction between actions a foreign state performs while exercising state authority (“acta iure imperii”) and actions performed in a private capacity as a private person (“acta iure gestionis”). The Federal Supreme Court ruled that a state may invoke immunity from legal jurisdiction exclusively for actions performed while exercising state authority. A foreign state may therefore be summoned before a Swiss court for acts performed in a private capacity, provided there is a sufficient connection between the civil law matter and Swiss territory.
The Federal Supreme Court reached the same conclusion with regard to immunity from execution, i.e. that it can only be invoked in respect of the property and assets of a state which are to be used for official state purposes. Consequently, property and assets may be seized if the state intends to use them in the capacity of a private person. Some elements of a state's property and assets are automatically presumed to be for use in the state's capacity as a sovereign authority. In particular, this includes property and assets used for the operations of diplomatic and consular representations, as well as those of the central bank or another state monetary authority.
The concept of state immunity followed by the Federal Supreme Court is in line with the jurisprudence developed by most states and is considered to have its foundation in customary international law. The United Nations Convention on Jurisdictional Immunities of States and Their Property of 2 December 2004 refers to the same distinction between “acta iure gestionis” and “acta iure imperii”.