The UK government had argued that the conditions imposed by the 1988 Act were justified on the basis that the Common Fisheries Policy allowed for a system of national quotas and the 1988 Act ensured the effectiveness of that system. This was rejected by the ECJ which stated that fishing vessel registration criteria were permitted, but not where they violated Community law. It was, in that respect, open to the UK government to introduce conditions ensuring that a "real economic link" existed between the ship and the State of registration, but such a link had to "concern only the relations between the vessel's operations and the population dependent on fisheries and related industries". In other words, it would have been possible for the UK government to prescribe conditions which protected UK fishing communities from the effects of the opening up of national fishing waters to other Member States, but it could not do that through the imposition of explicit nationality and residence conditions.