High Court rules Parliamentary approval required to trigger Article 50

There has been a lot of rhetoric and noise since 3 November, when three High Court judges ruled that Article 50 of the Treaty on European Union (TEU) – which would kick start the UK’s exit from the EU – could only be triggered with Parliament’s consent.

What’s clear is the decision is not a commentary on, as the official judgement states, the “question of the merits or de-merits of a withdrawal by the United Kingdom from the European Union; nor does it have any bearing on government policy, because government policy is not law”.

The High Court ruling does not have any impact on the referendum result or Government policy to implement it. Neither is it, as some commentators have suggested, a decision which runs roughshod over the democratic will of the people, but one which seeks to confirm the constitutional principles which enable that democratic will to be expressed. 

Unless there is a sharp change in Government policy or the will of MPs to implement the results of the referendum, Brexit will happen. And businesses should start preparing themselves for this now.

What was the court case about?

The only question which the court had to consider was whether the executive government was entitled to use its prerogative powers (i.e. powers traditionally held by the Crown but now passed to the Government to enable decisions to be taken without the backing of, or consultation with, Parliament) to give notice under Article 50 for the UK to exit the EU.

What was the claimant’s case?

The basis of the legal challenge – led by London-based investment manager, Gina Miller – was that the UK’s decision to enter the EU was made by Parliament when it passed the European Communities Act 1972 (ECA); the ECA, together with certain updating statutes, provided for EU law to have direct effect in domestic law. This gave UK citizens significant additional rights which could not be lawfully removed without the involvement of Parliament. In short, it was Parliament who had taken the decision to grant those rights, and it is only Parliament – and not the Government exercising its prerogative – that can take them away.

What was the Government’s position?

The Government argued it did not need Parliament’s approval of any decision to give notice under Article 50 because matters of international relations fell under the Government's general prerogative. The Government argued that if Parliament had wanted to curb this general right, it should have expressly done so in the ECA or later amending statutes.

What did the High Court decide?

The High Court agreed with the claimant. It concluded that whilst the Government had a general prerogative power to deal with international relations and make and unmake international treaties without Parliamentary approval, this was because in doing so it did not – and could not – change domestic law or confer or deprive individuals of rights. The TEU was not itself part of English law, but incorporated into it by domestic legislation which conferred rights on individuals; the Government, through the exercise of its prerogative powers, could not change domestic law in any way without the intervention of Parliament. 

The court concluded that, at a basic level, the Government’s position was “flawed” and failed to give value to “the usual constitutional principle that, unless Parliament legislates to the contrary, the Crown [i.e. the executive government] should not have power to vary the law of the land by the exercise of its prerogative powers”.


The Government has appealed the decision to the Supreme Court; a hearing has been listed to take place on 5 December 2016, with the decision scheduled for January.

If the decision goes against the Government, it will put significant pressure on its timetable for triggering Article 50 before 31 March 2017 as the process for obtaining parliamentary approval is unlikely to be a swift one. The Government could well be making plans behind the scenes for what will be put before Parliament in the event that the decision does not go its way. Even if it is, the Government will face an uphill struggle to get parliamentary approval of its proposed actions before the end of March even if, as some suggest, a full act of Parliament is not required. 

In a further twist, the Scottish and Welsh governments, who both held “watching briefs” but did not participate in the High Court proceedings, have indicated they will be applying to become formal interveners in the Supreme Court case.

The position taken by the Scottish Government in any permitted intervention should be watched with interest given Nicola Sturgeon’s commitment to protecting Scotland's position in Europe. Whether the Scottish intervention could result in MSPs voting alongside their Westminster counterparts on Article 50 being triggered also remains to be seen, but that possibility could provide a further headache to the Government and its Brexit timetable.  

Until the outcome of the Supreme Court appeal is known, the High Court decision is binding and the Government cannot lawfully trigger Article 50 without Parliament’s involvement. There is nothing to suggest that Brexit will not happen and the UK and its businesses need to continue to make the necessary preparations despite the procedural hurdles facing the Government.

If you would like to discuss any aspect of this article, please get in touch with Caroline Watson or your usual Thrings contact


Thrings Solicitors