It's sometimes said that the British constitution is based on two fundamental principles. The first of these is parliamentary sovereignty.

This states that the UK Parliament is not bound by any restrictions in terms of what it can do. The defenders of this system claim that it means that there can be no interference in a democratically elected parliament.

Less charitably you could also say that it is an example of an institution elected by a minority being able to do whatever it wants without having to observe any laws.

The second principle is that of the Rule of Law. This is a little bit more difficult to define precisely but it includes the idea that nobody is above the law and that people will receive a fair hearing from an impartial court which will take a decision without any interference.

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This week the UK government suggested proposals that would drive a coach and horses through the Rule of Law. They seem to want to be able to overturn court decisions through votes in the UK Parliament.

This is unprecedented in British history.

Ministers have always been in a position where their decisions can be challenged in the courts. Whilst the UK Parliament can do as it wants that has never applied to the UK government. The courts can quash decisions taken by ministers and suggest that they be looked at afresh and they can insist that Ministers follow the law when taking those decisions. Sometimes the UK Parliament changes the law as a result of a court decision but never looks to overturn the decision itself.

What the UK government now wants to do is to ignore the courts. Their proposal is that if Ministers don't like court decisions that go against them then they should be able to go to the UK Parliament and get it to overturn that decision.

On a practical level it means that where for example a group of people take action against the decision of a Minister because that Minister hasn't followed the law and the court agrees with them, that Minister can simply ignore the court ruling and have it overturned by their mates in Parliament. That is a fundamental attack on the Rule of Law.

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It also introduces a political element to the legal process. Whereas the courts are impartial and impervious to political pressure, letting the UK Parliament take decisions to overrule the courts is to allow a biased, less-than-objective institution the ability to take a decision that isn't based on evidence or fairness or the law but on politics.

No doubt jealous eyes have been cast on events in Hungary and Poland where the governments there have tried to reduce the courts’ ability to enforce the law and hold the government to account.

Government Ministers don't like it when they have had decisions overturned by the courts. It's happened to me. While I didn't agree with the decision, I accepted it.  That's why we have courts in the first place, to ensure there is a system that looks at what Ministers do and decides whether what is done is correct. That has always been accepted by the Welsh Government and I cannot imagine a situation where Welsh Ministers would want to control the courts in this way.

There are those of course to say that an elected parliament should always trump a court. In that case why not just let why not just let that parliament do as it wants when it comes to court cases? Why bother to have trials at all when you could simply lobby the UK Parliament to find in your favour or to overturn a court decision?

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When politicians try to put themselves above the law, they undermine the Rule of Law and start to corrode the British state from within. Regardless of party politics that is surely something no sensible democratically-inclined person would support.

That is also a challenge here for the Supreme Court. If these proposals go through, I have no doubt that at some point they will come before the Supreme Court. That court has always expressed its support for parliamentary sovereignty and for the Rule of Law but what happens when the two clash? What happens when you have a situation when the Rule of Law is discarded by Parliament for the benefit of an elite hierarchy of ministers in Whitehall? Will the court adhere to parliamentary sovereignty or will it come down in favour of the Rule of Law?

One thing the Supreme Court will not be able to do is to avoid the question and I suspect that in answering that question they may well trigger a constitutional debate the like of which has not been seen for many years.

UK Ministers need to understand that they, just like everybody else, have to submit to the law. They cannot be put in a position where they alone do not have to observe the law when they take decisions.

That is the road to semi-dictatorship and would destroy the principles upon which the UK state is based.

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