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Update: On 11 September 2019, the Scottish judgment was overturned on appeal and the Prime Minister’s suspension of Parliament was found to be unlawful. Number 10 is appealing to the Supreme Court.

If we can all agree on one thing about Brexit, it is that it has dominated the news since the 2016 referendum. Confusion abounds. Are we actually leaving the EU? Is 31 October a hard exit day deadline? How can MPs block a no deal exit? More fundamentally, can we find a satisfactory route through the process which respects the UK’s Constitution?

This last question was famously considered in Miller in 2017 and has most recently resurfaced in the reaction to the Prime Minister’s advice to the Queen to prorogue Parliament from mid-September until 14 October 2019. The emergency debate on the prorogation issue which took place in Parliament on 3 September 2019 demonstrated the seriousness of the constitutional situation, sitting as it did alongside three related judicial review challenges (the prorogation challenges) already taking place in courts around the UK. The first challenge was submitted earlier this summer in Scotland by a cross-party group of MPs on the basis that prorogation would be unlawful because it would:

  • deny Parliament sufficient time before exit day to scrutinise any proposal to leave the EU (including a no deal exit), thus contravening the sections of the European Union (Withdrawal) Act 2018 that mandate parliamentary scrutiny of the terms and dates of Brexit itself; and
  • undermine the separation of powers, which is a fundamental principle of the UK’s constitutional tradition. Although clearly a constitutional issue, the petitioners argued that it is justiciable because the Crown’s power to prorogue Parliament is now covered by statute and the court’s function is to interpret the law. They argued that just because a legal decision has political consequences does not mean that the courts should not be able to rule on it.

The Court of Session heard the matter substantively on 3 September 2019 and dismissed the application the next day, ruling that the matter was non-justiciable as it is a matter of political judgment, not law, and accordingly that the prorogation is lawful. The ruling is expected to be appealed. Parallel challenges were submitted by Gina Miller in London (heard on 5 September 2019 and refused on 6 September 2019) and Raymond McCord in Belfast (due to be heard substantively in the next week). Gina Miller is going to take her case on appeal to the Supreme Court, and it is expected to be heard on 17 September 2019.

Checks and balances

In the wake of the widespread uncertainty that Brexit has occasioned, it is perhaps unsurprising that the Courts have been asked to adjudicate on matters with an obvious political complexion. Historically, the success of the UK’s constitutional arrangements lies in an effective system of checks and balances, supported by an appropriate separation of the powers vested in Parliament, the Executive and the courts respectively. Of course, that balance can be struck with a degree of flexibility to meet the requirements of the day. Brexit, however, has given rise to pointed criticism of the actions of all three branches of the State, with claims that each of them has overreached at different points in the process. Is this criticism justified in so far as it relates to the judiciary?

Privacy International

The recent case of Privacy International provided a stark illustration of the extent to which there is disagreement about the right response to the criticism referred to above, not least amongst the judiciary themselves. The case saw the Supreme Court consider the separation of powers between the judiciary and the executive in the context of ouster clauses – that is statutory clauses intended to exclude judicial review of the acts and decisions of the executive.

Prior to Privacy International, the best known case to involve examination of an ouster clause was Anisminic. Anisminic Ltd brought an action against the Foreign Compensation Commission (FCC) for refusal of its application for compensation following the confiscation and sale of its property in Egypt. The action was brought on the basis that the FCC’s provisional determination was ultra vires: but Anisminic’s difficulty was that the relevant legislation (purportedly at least) contained a total ouster clause, excluding determinations by the FCC from being called into question. Accordingly, the action was dismissed.

On appeal, though, the House of Lords determined that any error of law made by a public body will make its decision ultra vires, and thus amenable to scrutiny by the courts, even if there is legislation that apparently excludes the court’s jurisdiction in that regard.

Privacy International had strong parallels to Anisminic, and focused on an ouster clause contained in Section 67(8) of the Regulation of Investigatory Powers Act 2000 (RIPA). Section 67(8) provides:

‘Except to such extent as the Secretary of State may by order otherwise provide, determinations, awards, orders and other decisions of the [Investigatory Powers] Tribunal (including decisions as to whether they have jurisdiction) shall not be subject to appeal or be liable to be questioned in any court’ (emphasis added).

On its face this provision seemed to exclude judicial scrutiny, and to do so even more strictly, and effectively, than the corresponding provision in Anisminic. Notwithstanding this, Privacy International applied for judicial review of the relevant decision in its case. The High Court adopted a strict construction of the legislation, and the Court of Appeal dismissed Privacy International’s subsequent appeal. On further appeal, the Supreme Court considered:

  • whether s67(8) RIPA ousted the supervisory jurisdiction of the High Court to quash a judgment of the Investigatory Powers Tribunal (IPT) for error of law (the First Question); and
  • whether, and, if so, in accordance with what principles, Parliament may by statute oust the supervisory jurisdiction of the High Court to quash the decision of an inferior court or tribunal (the Second Question).

The Court allowed Privacy International’s appeal by a majority (Lord Carnwath -delivering a judgment with which Lord Kerr, Lady Hale agreed – and Lord Lloyd-Jones). There were dissenting judgments from Lord Wilson and Lord Sumption (with whom Lord Reed concurred).

On the First Question, Lord Carnwath declared that judicial review can only be excluded by ‘the most clear and explicit words’, and concluded that where Parliament had not made its intention sufficiently clear, it was not for the courts to stretch the words used beyond their natural meaning. In reaching this view, he did not consider the exercise in which he and his fellow Justices were engaged as one of ‘ordinary statutory interpretation, designed simply to discern the ‘policy intention’ of Parliament’, but rather as a more complex assessment, taking account of a series of important contextual factors, and in particular the strong common law presumption against ouster.

At the other end of the spectrum, Lord Wilson considered that the plain words of the legislation should be the starting point. He was satisfied that those words excluded the possibility of judicial challenge to the IPT’s decisions etc., even on the grounds of error of law, and that that was Parliament’s intention.

Lord Sumption, meanwhile, in his dissenting judgment, suggested that the degree of clarity required in a provision intended to achieve a given aim would depend on the extent to which achievement of that aim would produce an anomalous effect. Ultimately, he did not think it controversial in constitutional terms to bestow on the IPT the adjudicatory powers which the High Court would otherwise have exercised as a court of review, especially given the nature of the IPT’s work in reviewing sensitive security decisions. Equally, though, he accepted that there was still scope for the courts to review certain challenges to the IPT, notwithstanding s67 (8), for example on the grounds that the IPT had exceeded its statutorily-prescribed subject matter competence.

The Justices were equally divided in their obiter comments on the Second Question. Lords Lloyd-Jones, Sumption and Reed declined to give a view. Lord Carnwath held that it is ultimately for the courts rather than the legislature to determine the limits imposed by the rule of law to the power to exclude review, and emphasised the need for respect for the different constitutional roles ascribed to the courts, and to Parliament, before concluding that that the scope of judicial review required to protect the rule of law was a question for the courts.

In dissenting, Lord Wilson answered the Second Question ‘Yes’, pointing to the requirement for the IPT’s President to hold or have held high judicial office, for its other members to have or have held similarly high judicial office or be UK lawyers of not less than 7 years qualification, and for the IPT to apply judicial review principles in exercising its jurisdiction.

How does this relate to Brexit?

The key point about Privacy International for present purposes is that, on one view at least, the majority in the Supreme Court sanctioned a move away from the traditional touchstone in statutory interpretation cases of Parliamentary intention to other guiding factors, thus creating a risk of future, and much more direct confrontation between Parliament and the courts.

The prorogation challenges have heightened fears – in certain quarters at least – of just that sort of clash. Lord Sumption, now retired from the Supreme Court, but invited to deliver this year’s Reith Lectures, has voiced concerns that the judiciary have been drawn in inappropriately to the determination of matters of high politics and policy, as opposed to law, particularly in interpreting human rights law too expansively. He foresaw that the challenges to the prorogation of Parliament were likely to face an uphill struggle, being legal challenges to a political issue, and considers that any disregard of constitutional conventions by the Prime Minister, although perhaps politically unwise, would not be unlawful.

Other equally eminent lawyers and judges, current and former, take a different view, and argue with equal vigour that the judges have successfully walked the fine line between matters properly for them, on the one hand, and matters firmly for politicians, on the other.

Ironically, the courts in London, Edinburgh and Belfast are now being asked to determine whether they are indeed the correct arbiters of the constitutional questions to which Brexit gives rise. The early indications from the Court of Session are that the Judges will be slow to decide that they are. Equally, though, the unsuccessful petitioners are seeking to appeal, so the question is far from settled; and, of course, the court in Northern Ireland may take a different view from the outset.

Where does this leave us?

Brexit is throwing up uncomfortable challenges for Parliament, the judiciary and the Executive. Each must rise to these challenges if the UK’s Constitution is to survive the current onslaught and adapt to the demands of our modern and rapidly evolving world. Nobody promised that the exercise of effective constitutional checks and balances would be pretty or painless; and, arguably, the current turmoil provides the strongest possible evidence that the system is working.

For Brexit updates, subscribe to our Brexit blog.

For further information on Parliamentary Law and Judicial Review, please contact Matthew Smith or David Mundy.

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