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Professor Mark Elliott Constitutional Expert on Cherry and Miller 2.
My own view is that the Divisional Court’s stance on what should be regarded as non-justiciable is far too broad, and that the position it reaches does not withstand analysis. In particular, the Court places disproportionate emphasis on the fact that it cannot make abstract determinations of how long is too long when it comes to prorogation, while approaching the whole issue of justiciability in unnecessarily sweeping terms that pays insufficient regard to the more subtle approach that courts have adopted over the last 30 or so years following the House of Lords’ seminal judgment in GCHQ [1985] AC 374.
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The central issue in Cherry and Miller (No 2) is whether the advice tendered by the UK Government to the Queen concerning the prorogation of Parliament for five weeks is lawful or unlawful. Prorogation is accomplished through the exercise of a legal power in the form of a prerogative power, and advice tendered to the Queen concerning its use amounts to an exercise by the Government of prerogative power ancillary to the prorogation power itself. It is well-established that the mere fact that a power falls under the prerogative rather than taking a statutory form does not in and of itself render it non-justiciable or otherwise immune from judicial review. The default position is therefore that the normal principles of judicial review apply to the exercise of any given prerogative power.
Once our starting-point is clearly established, other crucial matters follow. First, and importantly, is the widely recognised principle that no governmental legal power is unfettered. All legal powers held by the Government are legally finite, and their boundaries are determined, among other things, by reference to the purposes for which they may and may not legitimately be used. There is no good reason why this should not apply in the case of the prorogation power and the Government’s ancillary authority to advise the Queen as to its exercise. It follows that those powers are legally limited, among other things, by reference to the purposes for which they may and may not legitimately be used. What those purposes are is a legal question for determination by courts in the ordinary way.
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In the Cherry and Miller (No 2) cases, the question is therefore whether the use to which the prorogation power has been put results in the boundaries of the power having been exceeded, with reference to any purposes for which the power may not lawfully be exercised. The Divisional Court in Miller (No 2) rightly notes that there are several purposes for which the power can lawfully be exercised. But the question here is whether the power has been used for a purpose for which it cannot be so exercised.
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Thus, far from requiring the Court to determine whether the duration is excessive, the issue in Cherry and Miller (No 2) requires the court only to determine whether, to begin with, prorogation was undertaken for a purpose that was legally impermissible because it lies outside the range of purposes for which the power can lawfully be deployed. This is a crisp question of constitutional law concerning the scope of the discretionary power to prorogue, as distinct from a question about whether discretion has been lawfully exercised. Such a question of law, about the scope of the Executive’s legal powers, is manifestly one that lies within the field of matters with which courts can properly deal.
The result is that to approach Cherry and Miller (No 2) in terms of whether the courts can stretch the bounds of justiciability in a way that facilitates judicial scrutiny of the exercise of the prorogation prerogative is misconceived. It is misconceived because the legal issue at stake is not one upon which the non-justiciability doctrine can properly bite. That doctrine is concerned with limiting judicial involvement in the evaluation of the exercise of governmental powers whose use is capable of giving rise to questions that are unsuited, under the separation of powers, to analysis by courts on legal grounds. The justiciability doctrine is, however, logically incapable of biting upon questions about whether a given power exists and, if so, what its legal boundaries are. Questions about the purposes for which legal powers can and cannot lawfully be used are legal questions about the scope of such powers. It is questions of precisely that nature which are raised by the Miller (No 2) and Cherry cases. Consequently, the non-justiciability doctrine has no relevant application — and the suggestion by the Divisional Court that the “political” nature of the issue shields it from judicial review is entirely wide of the mark. Whether the Supreme Court will be prepared to treat the matters before it as justiciable remains to be seen, but there is no good legal reason for treating them as non-justiciable.
I think I've picked up the most important bits here.
Mark Elliott is seen as influential and very well regarded in his constitutional arguments. If memory serves I think his argument about A50 was roughly what the Supreme Court ruled in the end.
I think the argument he is trying to make here is that both the Scottish Court and the English High Court were wrong in their judgment, and that there's a third way in between what the two ruled. He argues that rather than it being a complex and controversial constitutional issue its a lot more simple.
He seems to lean towards it being a justiciable issue, but isn't sure the Supreme Court will share that view.