While foreign sovereigns are generally immune from falling under the jurisdiction of US courts, the Foreign Sovereign Immunities Act (FSIA) provides that state sponsors of terrorism are no longer protected from being sued in US courts if certain conditions are met.
Once a court acquires jurisdiction over a foreign sovereign, it also has jurisdiction to compel compliance with its orders. In the case of Peterson v. Islamic Republic of Iran, the judgment creditors sought post judgment discovery responses from Iran to aid in the collection of a $2.7 Billion judgment. Iran failed to respond to the discovery requests, and the court entered an order compelling discovery.
View the order here
Citation: 2008 WL 8216327