In 2008, the UN Security Council adopted resolutions calling upon States to co-operate in determining jurisdiction, and to investigate and prosecute persons responsible for acts of piracy or armed robbery off the coast of Somalia, consistent with applicable international law.

In response to those resolutions, the EU conducted a military operation known as Operation Atalanta to combat piracy off the Somali coast. In connection with that operation, the EU Council sent the EU Parliament a letter stating that a representative of the EU had been authorised to negotiate with certain countries, including Tanzania, pursuant to art 37 of the Treaty on the European Union (TEU), which permitted the EU to conclude international agreements in areas of common foreign and security policy (CFSP), for which a specific procedure was provided in art 218(6) of the Treaty on the Functioning of the European Union (TFEU), which excludes any participation of the Parliament. Following the completion of negotiations with Tanzania, the EU Council informed the EU Parliament that it had adopted Council Decision 2014/198/CFSP (the Decision) on the conclusion of an agreement between the EU and Tanzania. 

The Parliament brought an action before the CJEU for the annulment of the Decision on the grounds that: (i) the Agreement had a twofold purpose relating both to the CFSP and to the fields of judicial co-operation in criminal matters and police co-operation, fields which were subject to the ordinary legislative procedure; as such, the Decision should not have been adopted in accordance with the specific procedure for agreements that relate exclusively to the CFSP which excludes any participation of the Parliament; and (ii) the EU Council had failed to keep it 'immediately and fully informed at all stages' in the negotiation and conclusion of the Agreement.

In its defence, the Council contended that the Decision was correctly based on art 37 of the TEU and the first clause of the second subpara of art 218(6) of the TFEU, and that the adoption of the Agreement, which related exclusively to the CFSP, did not need the consent of Parliament. The Council also contended that the provision of the TFEU was not infringed because the Parliament was informed of all relevant decisions that the Council adopted with respect to, among others, the authorisation to open negotiations, the negotiating directives, the signature and conclusion of an international agreement, and, when appropriate, the provisional application of such an agreement. 

Held: The Decision was annulled, but the effects of the Decision were maintained.

The Agreement defined the conditions and modalities for the transfer from the EU force to Tanzania of persons detained, and associated seized property, and for their treatment after such transfer. Admittedly, some of the obligations laid down by the Agreement appear, at first sight, to relate to the field of cross-border judicial co-operation in criminal matters and police co-operation, when they are considered individually. However, the fact that certain provisions of such an Agreement, taken individually, have an affinity with rules that might be adopted within an EU policy area is not, in itself, sufficient to determine the appropriate legal basis of the Decision. As regards, in particular, provisions of the Agreement concerning compliance with the principles of the rule of law and human rights, as well as respect for human dignity, it must be stated that such compliance is required of all actions of the EU, including those in the area of the CFSP. That being the case, the Court must also assess that Agreement in the light of its aim.

The Agreement is designed to establish a mechanism that is an essential element in the effective realisation of the objectives of Operation Atalanta, in particular in that it strengthens, in a lasting way, international co-operation with respect to preventing acts of piracy, by defining a legal framework for the transfer of persons who are arrested and detained, which makes it possible to ensure that those persons do not go unpunished, in accordance with the mandate laid down by the relevant Security Council resolutions.

In that regard, it must be recalled that the Security Council requested all States to co-operate in determining jurisdiction, and in taking action to investigate and prosecute the perpetrators of acts of piracy and armed robbery off the coast of Somalia. Reflecting the co-operation envisaged by art 100 of the United Nations Convention on the Law of the Sea 1982 (UNCLOS), which imposes on the contracting States an obligation to co-operate in the repression of piracy on the high seas, it is an element of that international policy of combating acts of piracy and, in particular, of ensuring that the perpetrators of such acts do not go unpunished, that the Decision was adopted with a view to the signature and conclusion of the Agreement.

Accordingly, an examination of the aim of the Agreement confirms that the procedure of transferring persons arrested or detained established by the Agreement constitutes an instrument whereby the EU pursues the objectives of Operation Atalanta, namely to preserve international peace and security, in particular by making it possible to ensure that the perpetrators of acts of piracy do not go unpunished.

Since the Agreement fell predominantly within the scope of the CFSP, and not within the scope of judicial co-operation in criminal matters or police co-operation, the Decision could legitimately be based on art 37 of the TEU alone, and accordingly, its adoption in accordance with the procedure that excluded any participation of the Parliament was correct.

However, since the Council had failed to transmit to the Parliament either the text of the Decision or that of the EU-Tanzania Agreement, it had failed to inform the Parliament immediately and fully in the course of the procedure by which the Agreement had been negotiated and concluded. Therefore, the Council infringed the TFEU, and accordingly, the Decision was to be annulled. But, since annulment of the Decision without maintenance of its effects would be liable to hamper the conduct of operations carried out on the basis of the Agreement and, in particular, to jeopardise the prosecutions and trial of suspected pirates arrested by Union naval force, the effects of the Decision must be maintained.