Supreme Court finds that Brexit must be triggered by Parliament – BUT no need to obtain consent from the devolved governments in Scotland, Wales & NI.

In what is the most important constitutional decision in decades, the Supreme Court ruled this morning by a majority of 8:3 that the UK Government cannot trigger Article 50- which would facilitate the UK’s exit from the European Union- without an authorising act of Parliament.

The judgment sets out a clear limit to the Government’s prerogative powers, and whilst it has a general power to change international treaties, it cannot do this without legislation if changing the treaties would affect people’s rights.

The Supreme Court also unanimously found that the UK Parliament had no legal obligation to obtain consent from the devolved governments in Scotland, Wales and Northern Ireland to pass legislation to trigger Article 50. Whilst there was a convention for the UK Parliament to obtain such consent if UK-wide legislation would affect devolved matters, there was no legal obligation for this. To underline this, the Supreme Court concluded that foreign affairs matters are “reserved to UK government and parliament, not to the devolved institutions” and “the devolved legislatures do not have a veto on the UK’s decision to withdraw from the EU.”

While the judgment clarifies the legal mechanism to achieve Brexit, the complex politics will now dominate. It is difficult to envisage that Parliament would have the political appetite to block Brexit and the triggering of Article 50 this March, and the devolved governments have no legal ability to frustrate the process. It remains to be seen what extent the UK Government consults with the devolved governments on Brexit, and whether this will fuel public demands for a second independence referendum in Scotland and impact the Northern Ireland elections scheduled in March.

In Wales (which also voted to leave the EU) the first minister and Plaid Cymru's leader have published a plan for Brexit, calling for freedom of movement rules to be linked to whether migrants have a job. The white paper, launched by Carwyn Jones and Leanne Wood in London, demands full single market access on the basis that both Welsh Labour and Plaid Cymru see full single market access as essential for Wales’s economic success. However the UK Government has made it clear that the UK will not remain a member of the Single Market and it will take back control of immigration once the UK leaves the EU.

The profound implications of Brexit are still playing out and the differences in attitude and approach between the Westminster Government and the Devolved Governments will be an ongoing source of tension as we approach the triggering of Article 50 in March of this year.

Can the government trigger article 50 without a parliamentary vote? 

The court ruled that the government cannot trigger article 50 without an authorising act of parliament, Lord Neuberger, the president of the supreme court, said in his summary of the decision.

Explaining the decision, which the 11 judges reached by a majority of eight to three, Neuberger said the government generally has a prerogative power to change treaties, but it cannot do that if it will affect people’s rights.

“The change in the law required to implement the referendum’s outcome must be made in the only way permitted by the UK constitution, namely by legislation,” the judges said in the summary of their judgement.

They added: “The supreme court holds that an act of parliament is required to authorise ministers to give notice of the decision of the UK to withdraw from the European Union.”

Must the devolved assemblies be consulted?

Here the judges reached a unanimous decision: UK ministers are not obliged to consult the devolved assemblies, the court ruled.

The judges decided the relevant sections of the Northern Ireland Agreement were “not of assistance in this case”, and that the Sewel convention, by which Scotland usually has to give legislative consent to any legislation at Westminster affecting devolved matters, “does not give rise to a legally enforceable obligation”.

In their summary, the judges noted that the devolution acts “were passed by parliament on the assumption that the UK would be a member of the EU, but they do not require the UK to remain a member.”

They added relations with the EU and other foreign affairs matters “are reserved to UK government and parliament, not to the devolved institutions”, and concluded that “the devolved legislatures do not have a veto on the UK’s decision to withdraw from the EU”.

Where does this leave the government?

The government will be relieved that it does not need to consult the devolved assemblies;