## Facts

- U.S. utilities sued Westinghouse in federal court in Virginia for breach of long-term, largely fixed-price uranium supply contracts.
- Westinghouse defended on commercial impracticability/impossibility, alleging a global uranium shortage and price escalation caused in part by an international uranium cartel allegedly involving Rio Tinto-Zinc (RTZ) and others in England.
- The U.S. court issued letters rogatory requesting that English courts obtain testimony from RTZ officers and compel production of extensive documents about uranium production, marketing, pricing, and alleged cartel activity.
- England’s Evidence (Proceedings in Other Jurisdictions) Act 1975, implementing the Hague Evidence Convention, provided a mechanism for English courts to execute foreign letters of request.
- The English High Court initially ordered broad compliance with the requests.
- RTZ resisted, arguing the requests amounted to U.S.-style pretrial discovery, would expose RTZ to serious penalties under foreign or supranational competition laws, and risked facilitating U.S. antitrust enforcement activity beyond the civil contract case.
- While the English proceedings were pending, U.S. grand jury and enforcement interest increased the risk that materials gathered for the civil case could be used in U.S. antitrust investigations against foreign producers.
- The UK Government intervened in the House of Lords, asserting that far-reaching foreign antitrust investigations against non-U.S. persons abroad were objectionable as infringing UK sovereignty.
- The Court of Appeal substantially curtailed the discovery, recognizing protection where compliance would expose RTZ to serious foreign penalties.
- The dispute reached the House of Lords on RTZ’s appeal and Westinghouse’s attempt to secure broader assistance.

## Issues

1. Whether the Evidence (Proceedings in Other Jurisdictions) Act 1975 and the Hague Evidence Convention authorize English courts to compel broad, U.S.-style pretrial discovery of documents pursuant to letters rogatory.
2. How English courts should exercise discretion to grant, limit, or refuse foreign evidence requests when compliance may facilitate extraterritorial enforcement (including grand jury use) or conflict with UK public policy and sovereignty.
3. Whether assistance may be refused or narrowed where compliance would expose the producing party or witnesses to serious penalties under foreign or supranational law (including competition-law “blocking” risks).
4. What weight English courts should give to UK executive statements asserting that compliance would derogate from UK sovereignty.

## Decision

- The House of Lords largely upheld the Court of Appeal’s restrictive approach and confirmed that the broad discovery sought through the letters rogatory should not be ordered.
- The Lords construed the 1975 Act and the Hague Evidence Convention as instruments for obtaining specific evidence for use in identified civil proceedings, not for general exploratory discovery.
- The Court held that English courts retain discretion in executing letters of request and may restrict assistance to protect UK sovereign interests and avoid facilitating objectionable extraterritorial enforcement.
- The Court accepted that a real risk of serious foreign penalties or legal conflict for the producing party is a proper ground to refuse or limit compelled production.
- The Court treated executive statements on sovereignty and foreign relations as highly authoritative in assessing public-policy objections, while leaving the court to apply the statute and decide the scope of any order.

## Legal Principles

- The Evidence (Proceedings in Other Jurisdictions) Act 1975 permits assistance in taking evidence for foreign civil proceedings but does not mandate, and may not permit, broad pretrial discovery resembling U.S. practice.
- Letters of request should be confined to evidence that is identified with sufficient specificity and relevant for use in defined proceedings, and should not function as a “fishing” exercise.
- Execution of a foreign request is discretionary; courts may narrow, condition, or refuse assistance where compliance would offend domestic public policy, including concerns about sovereignty and jurisdictional overreach.
- Courts may refuse or limit production when compliance would expose a party to serious penalties abroad or force an untenable conflict between legal systems.
- Executive statements on matters of sovereignty and international relations carry substantial weight in the court’s discretionary analysis, though the court remains responsible for the legal decision.

## Conclusion

The House of Lords held that English judicial assistance under the 1975 Act must be directed to specific evidence for foreign civil proceedings and may be curtailed where broad discovery would risk foreign-penalty exposure or facilitate extraterritorial antitrust enforcement in a manner conflicting with UK public policy and sovereignty.


Rio Tinto Zinc Corp. v. Westinghouse Elec. Corp., [1978] A.C. 547 (H.L. 1978)