The letter, written by Mr Justice George Birmingham in his capacity as association president, outlines concerns among the judiciary about the impact of revised pension rules on recruitment.

Referring to an earlier meeting with commission chairman Kevin Duffy, he wrote: “I think, that at the meeting where we made our presentation we explained that our concern was not necessarily with the number of applicants but with the quality of applications.

“Some limited information does come into the public arena with the publication of the annual reports of the Judicial Appointments Advisory Board in relation to the number of applications but this is of limited assistance.

“For some courts at some periods there are very few applications but this is not necessarily a problem if the individuals applying are persons of the highest calibre.”

He said judges are concerned that “fewer applications are coming forward from really highly qualified candidates” as a result of “the cumulative effect of a number of decisions that were taken that affected the judiciary”.

Mr Justice Birmingham highlighted several decisions, including pay cuts following the 2011 referendum, but said the “most dramatic impact arises from the fact that a judicial pension is now deemed to have a particular value for pension threshold purposes”.

He continued: “The notional value of a High Court judge’s pension is equal to or exceeds the threshold limit. If the judge has a private pension fund from his or her time as a solicitor or barrister in private practice, that private fund is aggregated along with the judicial pension fund and the excess is subject to very high taxes indeed.

“The effect of this is to make a judicial appointment less attractive for a practitioner who has been responsible and has sought to make provision for their pension from their early days in practice.

“On the other hand, judicial appointment will be relatively more attractive for someone who chose not to or was not in a position to make provision for their retirement when in private practice.”