On 16 March 1978, the tanker Amoco Cadiz, while under tow after having lost both an anchor and its hydraulic steering mechanism, went aground and became stranded on rocks off the coast of Brittany, France. The Amoco Cadiz was on its way from the Persian Gulf to the Netherlands, laden with approximately 220,000 tons of crude oil. In rough waters, the disabled tanker broke apart on rocks, disgorging its cargo. Plaintiffs filed three class actions based on the pollution of the Breton coast and marine environment. Actions were removed to the federal court and plaintiffs filed motions to remand. Plaintiffs argued that these cases were based on the tort of negligence and that federal jurisdiction did not exist. In support, the plaintiffs pointed out the fact that the complaints filed did not plead claims contingent upon federal statutes or the International Convention of Civil Liability for Oil Pollution Damage 1969 (CLC 1969).

Held: Remanded.

Federal jurisdiction exists where ‘a suit arises under the Constitution, laws or treaties of the United States where it actually and substantially involves a dispute or controversy concerning the validity or interpretation of such federal issues, the determination of which will have a direct impact on the plaintiff's success or failure’. The mere relevance of federal issues is insufficient to invoke federal jurisdiction. If the treaty concerns collateral or secondary issues rather than an essential allegation of the complaint or the existence of a right of action, federal jurisdiction may not be invoked. If the construction or interpretation of a treaty will determine the plaintiff’s success, then federal question jurisdiction does in fact exist.

The court explained that the United States is not a signatory to CLC 1969. Therefore, the plaintiffs’ claims did not arise under CLC 1969. It would be incongruous to find in favor of the exercise of federal jurisdiction more readily in the case of a treaty to which the United States is not a party.

In addition, the court held that the plaintiffs’ claims did not arise under federal common law because issues involving the CLC 1969 may be controlling in the prosecution of, or defence to, the plaintiffs’ claims. Thus, plaintiffs’ claims did not actually and substantially involve a dispute or controversy concerning the interpretation or effect of the CLC Convention, the determination of which would have a direct impact on the plaintiffs’ success or failure. Accordingly, the cases were remanded to the state court.