Spanish fishermen took action against the United Kingdom. British law required boats to have majority British shareholders if registered in the UK.
The court found that it had the power to suspend an act of Parliament pending trial and even to disapply it when it conflicted with EU law. Merchant Shipping Act was prevented from operating temporarily and eventually struck down.
These cases went on until 1996. They were time barred by the Limitation Act 1980.
Dicey taught that there was legislative supremacy. Vide Bagehot. Some people believed parliamentary sovereignty had been fatally wounded since courts could overrule the will of the people.
The ECJ has the final say over issues that are EU matters.
Lord Justice Laws in Thoburn v City Counciil of Sunderland said that the EU cannot and does not overrule the UK Parliament. Seems to contradict Factortame.
Lord Denning previously said that British courts would recognise a UK law that broke a European one.