Outside of the scholarship of international law, treaties rarely become known by name – although many a Conservative MP could probably tell you where they were when Maastricht was signed.

Still less commonly does an individual article become known by name. Article 51 of the UN Charter, the right to act in self-defence, became briefly notorious in the run up to the Iraq war, but normally chapters and provisions normally sink into obscurity, beyond the specialised communities of lawyers and bureaucrats tasked with their interpretation and application. Article 50 TEU, of course has changed that, leaping out from the Lisbon Treaty, and onto a thousand front pages.

Institutionally, the path towards Brexit is clear. The Council will mandate, the Commission will negotiate and the Parliament and the Council will vote. But, as Emerson reminded us, ‘an Institution is the lengthened shadow of one man’, and so, with Article 50 triggered, attention is turning to the personalities who will be at the table – or on the menu.

First of all is Donald Tusk, President of the European Council since 2014.  Visibly emotional on receiving the formal confirmation that Article 50 was being triggered, the institution of which he is President ultimately must channel the demands of the 27 remaining member states into a negotiating mandate for the commission. This is unlikely to be a harmonious task, and the early inclusion of a Spanish interest over Gibraltar may well be a taste of the specific national interests that will rise in the bargaining to come. The impact of the poisoned relations between the current Polish government and Tusk on the Brexit process remain to be seen.

The legal basis for the process can be found in Article 218(3) of the Treaty on the Functioning of the European Union, which provides for the Council to authorise the opening of negotiations. The actual discussions between the UK and the EU, however, will be carried out by a Commission team headed by Michael Barnier. Three times a cabinet minister of France – including for Foreign Affairs and European Affairs – Barnier interspersed national roles with high level European jobs, serving as commissioner first for Regional Policy and later for Internal Market and Services.  This last post, which included responsibility for the financial services package following the 2008 crash, led to him being described as ‘the most dangerous man in Europe’, due to his oversight of financial regulation.

On top of his service in the College of Commissioners, he also served as VP of the EPP from 2010 to 2015. Following that, he acted as an unpaid advisor on defence to Juncker, before being appointed as Chief Negotiator in charge of the Preparation and Conduct of the Negotiations. Despite this undoubted wealth of experience, questions have been asked as to how much independence Barnier will enjoy, with Politico noting that his team will have to report to one of Juncker’s aides, Richard Szostak, who will oversee the work of the negotiating team on behalf of Juncker’s chief of staff Martin Selmayr. Thus the line of oversight over Barnier runs to the top of the commission, meaning that, combined with his duty to report back to the Council on the negotiations, Barnier is a man with two masters.

The overall team is expected to be pulled from across the EU, with Politico giving a round-up of the 30 or so known at this stage; some stand-outs include François Arbault and Stefaan de Rynck, both financial service experts, along with Sabine Weyand, former deputy-director at DG Trade and now deputy Chief Negotiator. The composition of the team course reflects the nature of the game; lots of expertise needed on finance, lots of input expected from member states, and lots of cooperation needed from each Commission department.

On the Parliamentary side, Guy Verhofstadt heads up the negotiating team. Formally, the Parliament has no role until negotiations have been completed, however Verhofstadt was never expected to wait in silence until 2019. Probably the most active – and engaged – EU politician on social media, his twitter account has been jam-packed with Brexit news since he was appointed to the role in September. Whether praising Britain’s contribution to the EU, chastising Boris Johnson for intemperate comments about punishment beatings, or advocating for an associate EU citizenship for post-Brexit Britons, his contributions have been both vocal and unique. On the institutional side, the Parliament – and thus Verhofstadt – has sought to make its mark already in two ways; firstly by stating that six months will be needed for them to consider any EU UK deal before voting, thus shortening the 2 year Article 50 negotiation time by a quarter, and secondly by the resolution, prepared by the heads of four of the eight political groups, detailing Parliament’s interests and their expectation that the Council will take their views into account during the framing of the negotiation guidelines.

Beyond the institutions, a few wildcards exist on the European side. Germany will go to the polls in September, with Martin Schultz, departing President of the European Parliament hoping to succeed Angela Merkel. Schultz is perceived to be a Brexit hardliner, although that may well change if his political hinterland orientates from Brussels to Berlin. At the opposite end of the Europhile spectrum Marine Le Pen is now trailing in the French Presidential elections, but if she follows the pattern set by the election of Trump and Brexit in the last year, the effect of a Front National President being part of the European Council is unlikely to further the goal of harmonious negotiations.

The likelihood is that, the final agreement will not happen solely between the UK and the institutions. As we have seen in the troubled ratification of CETA, and also in the opinion that AG Sharpston submitted to the European Court of Justice concerning the EU- Singapore, there are strong signs that any future, comprehensive trade deal will be a ‘mixed’ agreement. This means that individual member states must also agree – on the basis of unanimity – to the deal. Depending on the constitutional framework in place, that can mean an effective veto for regional assemblies, as briefly appeared possible when Belgian found itself unable to sign the final agreement due to the opposition of its French speaking region, Wallonia. As such, a final key player in the negotiations will be the unknown member state. There will be 27 national interests to be considered in the final agreement. Already in the draft negotiating mandate released by the Council, we saw the explicit recognition of a Spanish veto over future Gibraltar- EU arrangements. Furthermore, It is broadly expected that the UK will lose economically and politically by Brexit, and we can expect to see the negotiation mandates protecting the interests of the Union as a whole – but also reflecting the scramble for Britain, as member states attempt to restructure the deal in their own favour. This can be seen already in the tactical struggles surrounding passporting rights on financial transactions, as both France and Germany presumably position themselves to receive a share of the City. Other interests, will, no doubt, arise during the negotiations or at the ratification stage, when the threat of a national veto could plausibly cause the negotiations to be set-aside. Thus it will be appreciated that while Brexit may now be inevitable, a smooth and orderly process is far from guaranteed.

Brexit key players