Constitutional Conventions in UK Law

It, therefore, behoves the courts to be ever sensitive to the paramount need to refrain from trespassing upon the province of Parliament or, so far as this can be avoided, even appearing to do so.

Against that background, it would clearly be a breach of the constitutional conventions for this court, or any court, to express a view, let alone take any action, concerning the decision to lay this draft Order in Council before Parliament or concerning the wisdom or otherwise of Parliament approving that draft. The exercise upon which Parliament would be engaged and that upon which we are engaged are essentially different.

The first of those principles is particularly relevant to the use to which certain Parliamentary material may be put, and is considered later. The court in that case was willing to consider whether such an Order, if approved by Parliament, would be ultra vires the enabling statute, but made very clear the care that needed to be exercised in relation to the limits of the court's role.

In our judgment, it is clear that the introduction of a Bill into Parliament forms part of the proceedings within Parliament. To order the defendants to introduce a Bill into Parliament would therefore be to order them to do an act within Parliament in their capacity as Members of Parliament and would plainly be to trespass impermissibly on the province of Parliament.

It is the general right accorded to all litigants not to have the outcome of any pending appellate or other legal process pre-empted by executive action. By ratifying a treaty which provides for individual access to an international body, the Government made that process for the time being part of the domestic criminal justice system and thereby temporarily at least extended the scope of the due process clause in the Constitution.

It did not overturn the constitutional principle that international conventions do not alter domestic law except to the extent that they are incorporated into domestic law by legislation. It confirmed the principle that the consideration of a reprieve is not a legal process and is not subject to the constitutional requirement of due process, and that the Advisory Committee is not bound to consider, let alone adopt, the recommendations of the Commission.

When the court scrutinises the grounds relied upon for a certificate, it must do so necessarily against the background of the relevant circumstances and in the light of the decision at which the certificate is aimed. Disagreement with findings about such circumstances or with rulings of law made by the tribunal in a fully reasoned decision is one thing.