Treaty on European Union, Articles 2 and 19. Treaty on Functioning of EU - art. 157
Charter of Fundamental Rights of the European Union, Article 47

Wilson - C 506/04, Portugese Judges Asssociation C-64/16, "It follows from this case-law and, in particular, from the Portuguese judges and the Escribano Vindel judgments, that the Court has jurisdiction to interpret EU law in cases that relate to the organisation of a Member State’s judicial system, including the remuneration of judges".

The applicant XL was appointed as a judge at the Sąd Rejonowy w Suwałkach (District Court, Suwałki) on 4 December 2003 by order of the President of the Republic of Poland. On 3 April 2007, by decision of the Minister for Justice, he was seconded to the position of judge at the District Court, Białystok, where he has been working in a judicial function ever since.

From 5 August 2021, the applicant was assigned to basic pay grade five with a basic salary multiplier of 2.5 and a years-of-service supplement at 20% of the basic salary.

The applicant’s salary for 2022 was calculated using a multiplier of 2.5 and the basic salary set at PLN 5 050.48.

The applicant’s salary for 2023 was calculated using a multiplier of 2.5 and the basic salary set at PLN 5 444.42.

In his opinion delivered on 13th June 2024, AG Collins found questions admissible and decided:  "The second subparagraph of Article 19(1) TEU
must be interpreted as not precluding the legislative and/or the executive of Member States from making laws to determine and/or to reduce judges’ remuneration, including by way of collective agreements made in accordance with national law.

as requiring Member States to lay down a legal framework to facilitate the determination of judges’ remuneration that seeks to protect judicial independence through ensuring that the level of judges’ remuneration is commensurate with the importance of their functions. Laws governing judges’ remuneration must operate on the basis of relevant, objective and verifiable criteria that respect the principle of proportionality.

as requiring that any assessment of the adequacy of the level of judges’ remuneration take account of all relevant socio-economic factors and refer to the evolution of that remuneration over time.

as requiring that any national law aimed at reducing the level of judges’ remuneration set out, in clear terms, the justification therefor. Such reductions in judicial remuneration as may result therefrom must be temporary and their amount and their duration tailored to, and evolve with, the gravity and persistence of the conditions that justified their adoption. Under no circumstances can such reductions target the judiciary for unfavourable treatment.

as requiring that rules on judges’ remuneration or any reduction thereof are subject to judicial control."