Treaty on European Union Art 6(2).
On 18th December, the Court of Justice of the European Union (CJEU) ruled that the draft agreement on the accession of the European Union to the European
Convention on Human Rights (ECHR) was not compatible with EU law.
See the Court's Opinion 2/13 and the associated Press release.
The CJEU is the ultimate authority on the interpretation of the law of the EU. The European Court of Human Rights - (which operates as an organ of the Council of Europe and not the EU) - is the ultimate authority on the meaning of the ECHR. It is fairly obvious that there could be a problem if two distinct courts held sway within the EU. However, it was widely thought that the proposed agreement would deal with any such problems. The CJEU, in a lengthy and complex opinion, disagreed. The following articles are well worth reading for more detailed discussion of the opinion and its potential consequences.
UK Constitutional Law blog 24th December
Cambridge Journal of International and Comparative Law 20th December
ECHR Blog 20th December
EU Law Analysis 18th December
Euractiv 19th December
Despite the obligation in the Treaty on European Union, Opinion 2/13 makes it highly difficult for the EU to proceed
with accession. The CJEU seems to have been especially concerned to maintain its own position as the ultimate authority on the EU legal order. The way forward is not yet clear but the Treaty obligation remains in place.