After being Justice of the UK Supreme Court from 2010-2, why did Lord John Dyson demote to Master of the Rolls from 2012-6?
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<p><a href="https://www.law.ox.ac.uk/people/lord-john-dyson" rel="nofollow noreferrer">Lord John Dyson was Master of the Rolls (President of the Court of Appeal of England and Wales and Head of Civil Justice) for four years until he retired in October 2016. He was a Justice of the Supreme Court of the United Kingdom from April 2010 until October 2012.</a></p>
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<p>As you can see from  the 2nd and 5th bullet points from below <a href="https://slideplayer.com/slide/10870142" rel="nofollow noreferrer">picture</a>, JSC (Justice of the  Supreme Court) outranks MR (Master of the Rolls).</p>
<p><img src="https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcRjJILDHJnXyFV7ZQip-lf8FoBx6mipS2kDXg&amp;usqp=CAU" alt="" /></p>
<p>Dyson demoted himself, or got demoted. Right?</p>
<p>But why this demotion? Did he bumble something? Why did he stop being JSC in 2012, and become MR?</p>

<p>&quot;Why&quot; someone did something is potentially off-topic, but in regards to your hierarchical image - it lacks provenance so cannot be tested, however according to the official <a href="https://www.judiciary.uk/about-the-judiciary/who-are-the-judiciary/judges/profile-mor/#:%7E:text=The%20Master%20of%20the%20Rolls%20is%20second%20in%20judicial%20importance,system%20and%20rights%20of%20audience." rel="nofollow noreferrer">judiciary website</a>:</p>
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<p>The Master of the Rolls is second in judicial importance to the Lord Chief Justice.</p>
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<p>This is from Lord Dyson's autobiography <em>A Judge's Journey</em> (Bloomsbury, 2019), with some hyperlinks added by me for context:</p>
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<p>The same restlessness and unwillingness to reject a new challenge as had propelled me rashly to move chambers in 1996 led me inexorably to decide to apply to become the MR. But the fact that it would be a new challenge was surely not a sufficient reason for taking this major decision. After all, I would be giving up sitting in the highest UK court to presiding in a lower court, the Court of Appeal of England and Wales. After I had been appointed as the MR, my good friend and colleague <a href="https://en.wikipedia.org/wiki/Brian_Kerr,_Baron_Kerr_of_Tonaghmore" rel="nofollow noreferrer">Brian Kerr</a> told me that he couldn't wait to overturn me. My decisions were liable to be reversed by my former colleagues; and even where an appeal from one of my decisions was dismissed, I would not have had the last word. As against that, for the only time in my judicial career, except when I was in charge of the <a href="https://www.gov.uk/courts-tribunals/technology-and-construction-court" rel="nofollow noreferrer">TCC</a>, I would be in charge and able to choose the cases I heard and the colleagues with whom I sat to hear them. And apart from the heavy case-load, there was the challenge of discharging numerous other responsibilities.</p>
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<p>He also describes that the competition was contested, but his application was prompted by the then Lord Chief Justice, <a href="https://en.wikipedia.org/wiki/Igor_Judge,_Baron_Judge" rel="nofollow noreferrer">Lord Judge</a>, who anticipated that the outgoing Master of the Rolls, <a href="https://en.wikipedia.org/wiki/David_Neuberger,_Baron_Neuberger_of_Abbotsbury" rel="nofollow noreferrer">Lord Neuberger</a>, was likely to be appointed President of the Supreme Court and that Dyson would be a good candidate to succeed him.</p>
<p>In all, as the book describes, Master of the Rolls is in some sense junior to being a Supreme Court justice, since decisions of the Court of Appeal could go to the Supreme Court for final determination. But the majority of cases don't: the civil division takes at least five to six hundred appeals in a typical year, compared to only dozens for the Supreme Court from <em>all</em> of the UK jurisdictions. So most cases that the MR decides will not be appealed, and he can be involved in many more cases (whether by sitting himself, or deciding which other Lord Justices of Appeal will sit). That is one reason why the job would be attractive to an energetic judge, even though he wouldn't always get the last word.</p>
<p>Dyson also describes several additional tasks which come along with the role, and help to give it a special identity and aura of prestige. Aside from the antiquity of the title, it is also one which has attracted various other statutory and traditional functions. Dyson was surprised to learn that he was <em>ex officio</em> a <a href="https://en.wikipedia.org/wiki/Commissioners_for_the_Reduction_of_the_National_Debt" rel="nofollow noreferrer">Commissioner for Reduction of the National Debt</a>, although not expected to do anything substantive as such. He ran <a href="https://www.gov.uk/government/organisations/civil-procedure-rules-committee" rel="nofollow noreferrer">the committee</a> responsible for the Civil Procedure Rules, an important behind-the-scenes way to have an effect on the entire civil justice system. As MR, he also enjoyed a higher individual profile than as a Supreme Court Justice in terms of public outreach, and involvement in various official and diplomatic events.</p>
<p>In comparison, he found his time on the SC to have more of an academic/intellectual character, as one judge among many, dealing in an intense way with a small number of cases. He also notes differences in style between the courts, with the SC using larger panels and having more tradition of issuing multiple opinions. Dyson also remarks that he did not find sitting on the Judicial Committee of the Privy Council (which comes along with being on the SC) particularly interesting, since he did not find himself engaged by a large part of its work involving criminal appeals from Commonwealth countries.</p>

<p>That hierarchy seems to be based on the court hierarchy.  Justices of the Supreme Court are listed above the Master of the Rolls because the Supreme Court sits above the courts in the division that the Master of the Rolls administers.  But the administrative duties of the Master of the Rolls apparently carry with them increased prestige and authority (along with <a href="https://www.gov.uk/government/publications/judicial-salaries-and-fees-2021-to-2022" rel="nofollow noreferrer">higher pay</a>).</p>
<p>Think of a corporate conglomerate.  Someone who is among several vice presidents of the parent corporation might similarly be in a lower position than the CEO of one of the subsidiaries even though the parent corporation has authority over the subsidiary.</p>

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