I have finally got around to writing a piece on one of my pet hates: the overuse of the phrase “as his/her Honour/Lordship/Ladyship then was”. This device is a (mostly) meaningless affectation that should be removed from the patois of lawyers.
I say “mostly” because there are a few circumstances where the use of this device is no mere affectation, but serves an important role in identifying a judicial officer who during their term of office comes to be referred to by a title that is divorced from their personal name.
For example, Sir Rufus Isaacs was the Lord Chief Justice of England from 21 October 1913 until 8 March 1921. The earliest report of a judgment by Isaacs in the Law Reports appears to be Walters v W H Smith & Son Limited  1 KB 595 where he was styled “Sir Rufus Isaacs CJ”. On 9 January 2014 Isaacs was created Baron Reading (on 9 January 1914). Thereafter, in the Law Reports he was styled “Lord Reading CJ”: see Allen v Great Eastern Railway  2 KB 243. On 3 July 1916 Isaacs was made Viscount Reading. In the Law Reports he was then styled “Viscount Reading CJ”: see R v Wheeler  1 KB 283 (there seems to have been a delay between the creation of the viscounty and his re-styling in the Law Reports). On 20 December 1917 Isaacs was made Earl of Reading. Thereafter, in the Law Reports he was styled “Earl of Reading CJ”: see R v Oxlade  2 KB 628.
In these circumstances, it makes sense to refer to “Sir Rufus Isaacs CJ (as he then was)” when citing a judgment from the period prior to him being made Baron Reading. This is because it alerts the reader to the fact that he is no longer known as Isaacs. But there would seem to be no necessity to refer to “Lord Reading CJ (as he then was)” because the peerage name continued from his barony, through the viscounty, into his earldom (and subsequently a marquessate). “Lord Reading CJ” is a sufficient identification of the individual who has subsequently attained a higher rank in the peerage.
A contemporary of Isaacs, Sir William Pickford, similarly held judicial office under his personal name before being made a peer with a title which no longer identified the individual (in this case, Baron Sterndale). Again, it would make sense to cite his earlier judgments by reference to “Pickford LJ (as he then was)” since he subsequently came be known in judicial office as Lord Sterndale MR. Similarly, in 1900 Sir Richard Webster was for a short period Master of the Rolls under the style “Webster MR” before continuing that role under the title Baron Alverstone and, the Law Reports, being styled “Lord Alverstone MR”.
The conferral of a peerage does not necessarily result in a change in identifying name, even for a newly-created peerage. Thus, Sir Robin Cooke’s elevation to Baron Cooke of Thorndon does not require the use of the device when citing his judgments from the New Zealand Court of Appeal. Similarly, Sir Kenneth Diplock was, upon his elevation from the Court of Appeal to the House of Lords, created Baron Diplock and again there would seem to be no necessity to refer to “Diplock LJ (as his Lordship then was)” when citing his judgments from the Court of Appeal.
It seems unnecessary to use the device where the person in question has attained a peerage after they have left judicial office. For example, Sir William Brett was made Viscount Esher upon his retirement from judicial office as Master of the Rolls in 1897. Unlike Sir Rufus Isaacs, whose judicial career includes judgments under the name Sir Rufus Isaacs as well as Lord/Viscount/Earl of Reading, Sir Willliam Brett’s judicial career was spent entirely under the name Sir William Brett.
Aside from the instances described above, where the use of the “as he then was” device serves the function of alerting the reader to the fact that the person has subsequently come to be identified by a title instead of their name, the device is unnecessary. What is the point of referring to “Mason J (as his Honour then was)”? Nobody is going to be confused about whether the then High Court puisne judge is the same person as the subsequent Chief Justice. A prompt is not needed to alert the reader to the fact that Sir Anthony was promoted during his tenure on the High Court, and that Mason J is the same person as Mason CJ. Nor is there a change in the identifying part of the name of the particular individual about which some reminder is needed. We do not now say “Mason CJ (as his Honour then was)”, even though he is no longer. It would hardly make sense to cite a judgment of Virginia Bell during her Honour’s tenure on the Supreme Court by saying “Bell J (as her Honour then was)”.
The judicial person held whatever position they held when a judgment was given, and the fact that they no longer hold that position or have subsequently been appointed to a different position is an unnecessary fact about their career progression that requires no reference when citing their judgment. It only becomes necessary (or at least useful for those unschooled in legal history) where a person’s elevation creates a potential confusion about identity.