It's like the English Civil War all over again, though this
time the Roundheads (Remainers) are fighting the Cavaliers
(Brexiteers) through the courts rather than on the battlefields of
the British countryside.
On 1 January 1973 the United Kingdom joined what were then known
as the European Communities. It was a condition of membership that
Community law should be given effect in domestic law. Primary
Legislation was required to achieve that. Consequently the European
Communities Act 1972 was passed.
The European Communities have now become the European Union.
Pursuant to the European Union Referendum Act 2015 a referendum was
held on 23 June 2016 on the question whether the United Kingdom
should leave or remain in the European Union. The answer given was
that the UK should leave.
The process for withdrawal is governed by Article 50 of the
Treaty on European Union.
The Government (the Roundhead Brexiteers) believe that, as a
matter of UK constitutional law, it is entitled to give notice of a
decision to leave the European Union under Article 50 by exercise
of the Crown's prerogative powers and without reference to
Parliament. The Cavalier Remainers say that Parliamentary approval
is required. A number of test cases were brought in the High Court
to challenge the Government's position. On Thursday it gave its
decision that Parliamentary approval was required. The Government
has appealed to the Supreme Court. We understand that for the first
time there will be a full sitting of all 11 justices of the Supreme
Court. This will therefore be the most significant constitutional
decision of modern times.
The most fundamental rule of the UK's constitution is that
Parliament is sovereign and can make and unmake any law it chooses.
As an aspect of the sovereignty of Parliament it has been
established (during the original English Civil War) that the
Government of the day cannot by exercise of prerogative powers
override legislation enacted by Parliament. This principle is of
critical importance and sets the context for the general rule on
which the Government seeks to rely - that normally the conduct of
international relations and the making and unmaking of treaties are
taken to be matters falling within the scope of the Crown's
In the present case, however, the Government accepts, and indeed
positively contends, that if notice is given under Article 50 it
will inevitably have the effect of changing domestic law. Those
elements of EU law which Parliament has made part of domestic law
by enactment of the 1972 Act will, as a result of the operation of
Article 50, in due course cease to have effect.
The central contention of the Government in the present case is
that Parliament must be taken to have intended when it enacted the
1972 Act that the Crown would retain its prerogative power to
effect a withdrawal from the Community Treaties (now the EU
Treaties), and thereby intended that the Crown should have the
power to choose whether EU law should continue to have effect in
the domestic law of the UK or not.
The High Court did not accept the argument put forward by the
Government. It said that the argument was contrary both to the
language used by Parliament in the 1972 Act and to the fundamental
constitutional principles of the sovereignty of Parliament and the
absence of any entitlement on the part of the Crown to change
domestic law by the exercise of its prerogative powers.
We await the decision of the Supreme Court listed for hearing on
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