Further express treaty-making powers were added in 1987 by the Single European Act
in the fields of research, technological development and the environment, and, after
Maastricht, in the fields of development cooperation and economic and monetary policy.
- The reason why we need to establish what is competence of the EU under the
functioning Treaty is to see which areas are covered by European law as
interpreted by the ECJ – for instance, CFSP is still kept outside to a large extent. If it
does not fall within the EU legal order in the sense of Van Gend en Loos then it is still
public international law. Then, we must ask ourselves to what extent can the ECHR
step in, since it is not a set of rules originating from the EU legal order and it does not
fall within the Bosphorus case law.
- Once the existence of EU competence is established, the next important question is
whether it is exclusive competence, or whether it is shared with the Member States
to the EU and that there is no concurrent Member State competence.
- One should keep in mind that EU legislation and ECJ jurisprudence are both
complementary and interactive, with the ECJ adopting the doctrine of effet utile, or
effectiveness in the interpretation of EU law. The ECJ systematically tries to give a
meaning or a full effect to the express provisions of the Treaty, many times
inspiring the legislator (think about the Cassis de Dijon case, that laid out the framework
for future harmonisation, or the rulings on the locus standi of the EP in Les Verts or
Chernobyl). There is a kind of dialectic – the poorer the legislative work, the more
prolific will the ECJ’s case law be.