Rio Tinto Zinc Corporation v Westinghouse Electric Corporation [1978] 2 WLR 81

The respondent were sued in US for breach of contract, they claimed that the appellants have rendered the contract impossible to perform which was in contravention of Sherman Act. At the respondent request a US judge issued letters rogatory to the courts in the UK to provide evidence, the letters were granted on basis of the 1970 Hague Convention on Taking of Evidence Abroad in Civil and Commercial Matters, after that, the US pretend to implement the letters in a Grand Jury investigation.

1. UK had made a declaration to the 1970 Convention objecting use of evidence in pre-trial discovery 2. The use of the letters in a Grand Jury investigation changed its character, to a purpose which was not intended. The extraterritorial investigation of the Grand Jury infringed the UK sovereignty. Therefore the appeal on implementation was allowed. Dilhorne: to exercise jurisdiction over foreigners in respect of acts done outside the jurisdiction of that country constituted an invasion of sovereignty and was contrary to international law