Yesterday morning saw seven QCs line up in court for a short hearing which represents the first step in proceedings to establish whether it will be the government or Parliament that triggers the process for the UK to leave the EU.

The parties

The hearing concerned two separate cases, both of which seek to argue that it is for Parliament rather than the government to trigger Article 50 and thus begin the process which will take the UK out of the EU. One was brought by Mr Deir Dos Santos, an unemployed hairdresser, and the other was brought by a Mr Mark Hardy.

There are, however, a number of other potential claims that seek to address the same point. The most prominent is that of Gina Miller, who is acting as potential lead claimant for a group of persons who have retained Lord Pannick QC, among others. There is also a campaigning group - 'Fair Deal for Expats' - representing a number of individuals who are resident or own property in France, which has indicated an interest in joining the proceedings.

In the face of numerous potential claimants, all seeking to advance the same arguments, the government asked the Court to direct that a lead claimant should be nominated with all the other potential claimants taking the role of interested parties if they still wished to participate.

The lead claimant will take primary responsibility for putting forward the arguments that Parliament, not the government, should trigger Article 50. The interested parties will be able to file submissions adding to the points raised by the lead claimant. However, the position of interested party carries with it a potentially significant downside - if the court decides that the submissions made by the interested party have not been of significant assistance to the court, that party could be liable for costs. Conversely, it is only in exceptional circumstances that an interested party will be able to recover the costs of their intervention.

In a surprising move, the Court - which consisted of Sir Brian Leveson, President of the Queen's Bench Division, and Mr Justice Cranston - held that Ms Miller should be the lead claimant, even though she is not currently a party to any proceedings. (She has undertaken to file her claim before the Court rises for its summer vacation on 29 July.)

There would seem to be two factors which led to that decision. The first is that Mr Dos Santos was seeking a protective costs order (a 'PCO') to proceed. In the ordinary course of litigation, the rule is that the loser will pay the winner's reasonable costs. However, a claimant who is granted a PCO has his liability to pay costs capped at a certain level if he loses. This is obviously unattractive from the point of view of the government as it limits the amount of costs that it can recover if successful.

By contrast, Ms Miller is an 'investment manager and philanthropist' and is said to be backed by a larger group of unnamed individuals who will presumably contribute to her war chest.

In addition, the choice of lead claimant may have been influenced by the counsel who will make her case. Ms Miller is represented by Lord Pannick QC - one of the most distinguished public law silks in the UK - and having such a weighty name behind her, together with her presumed ability to pay the government's bills if she loses, must have served to elevate her up the hierarchy of claimants.

The arguments

The hearing yesterday morning was not intended to include a full consideration of the substantive legal arguments advanced by either side. Indeed it would have been difficult for it to do so in circumstances where the new lead claimant has not actually lodged her claim yet and the government has not responded to the two claims which have been lodged.

We have discussed the arguments now put forward by the claimants in a previous alert. Those arguments were briefly summarised by Lord Pannick QC.

The government believes that the Prime Minister has the right to trigger Article 50, without recourse to Parliament, through the use of the royal prerogative. The claimants consider this view to be flawed as the royal prerogative cannot be used in areas which have been colonised by Parliament through statute. The purpose of the European Communities Act 1972 was to give domestic effect to EU law and that aim will be frustrated through the issue of an Article 50 notice as it will set in train a process which will lead to EU law ceasing to have effect in the UK. The decision should therefore rest with Parliament.

One preliminary issue that did not need to be considered at the hearing was the interim injunction sought by Mr Dos Santos to prevent the government triggering Article 50 before the case had finally been decided. This was because leading counsel for the government, Jason Coppel QC, confirmed that the government does not intend to trigger Article 50 before the end of the year which, as discussed below, will give the Courts time to fully consider the issue.

Next steps

The case will be listed for a full hearing, to take place over two or three days, not before 17 October. That hearing will take place in front of Lord Thomas, the Lord Chief Justice, together with two High Court judges, with the hope that judgment will be given in early November.

The losing side will then have the opportunity to appeal directly to the Supreme Court (skipping over the usual step of the Court of Appeal) in the hope of a final decision in the case before the Court rises for its Christmas break on 21 December.

The position will hopefully be clarified, therefore, before the earliest date on which the government might consider that an Article 50 notice should be issued.