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C-2/74. M. Reyners, a Dutch national, was prohibited from practicing as an advocate in the Belgian courts on the grounds that he did not have Belgian nationality. Such discrimination would be forbidden by (what is now) Art. 43 of the ECTreaty, but it was unclear whether Art. 43 haddirect effect. Under the principle of VanGendEnLoos1963, a Treaty provision would be directly effective if, inter alia, it were unconditional and did not leave any further implementation to the member states. However, in this case Art. 44 provided that the Commission would issue various directives creating the necessary legal obligations to give effect to Art. 43. These directives had not been created at the time the case was heard.

The ECJ held that the principle of Art. 43 -- non-discrimination on the grounds of nationality -- was clear. Despite the lack of specific directives, Art. 43 did prohibit member states from acting in particular ways, and it was therefore directly effective.

This case is interesting because it shows that, although the ECJ has frequently been criticised for taking an interventionist stance when member states have failed to meet their obligations under the Treaties, it is not averse to using direct effect to counter Community non-compliance as well.