A thousand lawyers have written to the PM to say that in their opinion the referendum result is merely “advisory” and that the decision to leave the EU or not must be decided by a vote in Parliament. Detailed legal arguments are lacking, and the exercise rather reminds one of Einstein’s response that, if he were wrong, “one would have been enough”.
The legal firm Mishcon de Reya has also written to the Government on behalf of a number of (thus far anonymous) clients, in similarly vague terms.
A good take down is provided by Lawyers for Britain. This is my take on it.
The power to make, break and act under treaties is exercised by Government Ministers using the Royal Prerogative (RP). Parliamentary approval is not, in general, required. There are two situations in which a Minister would need to go to Parliament:
a) For a decision that modifies an existing Act of Parliament. This would apply to repealing the European Communities Act (ECA), which would immediately take us out of the EU. But it does not apply to invoking Article 50 of the EU Treaty (A50), which leaves the ECA untouched, and keeps the UK in the EU during the stipulated two year period. A50 was added to the EU treaty by the Treaty Of Lisbon in 2007 and this was incorporated into UK law in 2008. So Invoking A50 is something that we do under the provisions of the EU treaty and the ECA and as such comes under the RP.
b) On matters where Parliament has explicitly required its approval to be sought. Some provisions of the Lisbon treaty are indeed subject to such a requirement, but A50 is not one of them. If Parliament wished to restrict Ministers ability to invoke A50 this would have been debated in 2008.
That is the dry legal argument pretty much out of the way. The PM has the power to invoke A50 and no approval by Parliament need be sought. There is really no serious doubt about this under UK law as it stands, and unless the signatories are hoping for an act of judicial activism of American proportions they are wasting everyones time. The constitutional points go deeper and are perhaps more interesting.
The description of the referendum as “advisory” is loaded. What is clear is that the referendum did not have any direct legal effect, such as repealing the ECA or invoking A50, in its own right. A court would certainly rule that neither event happened on 24 June this year. But is is equally clear that it was always intended that the referendum result would be binding on the Government, and that the decision of the people – in which ever direction – would be implemented.
The UK does not have a written constitution. But it is a long standing principle that a Government has a mandate to implement its manifesto commitments. The Conservative General Election Manifesto of 2015 said:
“We will negotiate a new settlement for Britain in the EU. And then we will ask the British people whether they want to stay in on this basis, or leave. We will honour the result of the referendum, whatever the outcome.”
Parliament passed the Referendum Act in 2015. It was made absolutely clear by the Government that the matter would be decided by the referendum and would not come back to Parliament. The word “advisory” appears nowhere in the Act or in the debates.
Mr [Philip] Hammond [Foreign Secretary]: …whether we favour Britain being in or out, we surely should all be able to agree on the simple principle that the decision about our membership should be taken by the British people, not by Whitehall bureaucrats, certainly not by Brussels Eurocrats; not even by Government Ministers or parliamentarians in this Chamber. The decision must be for the common sense of the British people. That is what we pledged, and that is what we have a mandate to deliver. For too long, the people of Britain have been denied their say. For too long, powers have been handed to Brussels over their heads. For too long, their voice on Europe has not been heard. This Bill puts that right. It delivers the simple in/out referendum that we promised, and I commend it to the House.
So it is clear that Parliament, in approving the referendum, was approving the intention of the Government to implement the outcome. Any MP who did not accept this would have had to vote against the Bill at second reading. Only 53 did so.
This promise was repeated during the referendum campaign itself in the leaflet (costing £9.5m) delivered to every household on behalf of the Government.
“This is your decision. The Government will implement what you decide.”
At no stage was it suggested that the referendum would be “advisory” and that the actual decision would be taken by Parliament. Given the promises made and repeated it seems unarguable that, while the referendum result does not have a direct legal effect, it is constitutionally and morally binding on the Government to implement it.
This is the first UK referendum to be answered in favour of change, so there is no precedent for what would happen if the Government or Parliament refused to implement the result. All that can be said for certain is that it would be regarded by those who voted Leave, and no small proportion of those who voted Remain, as a constitutional outrage.