Kathleen Hill and Ann Stapleton v The Revenue Commissioners and Department of Finance.
Date: 1998-06-17
18 It must be recalled at the outset that Article 119 of the Treaty sets out the principle that men and women should receive equal pay for equal work.  As the Court has already held in Case 43/75 Defrenne v Sabena (Defrenne II) [1976] ECR 455, paragraph 12, that principle forms part of the foundations of the Community.
22 As the Court held in Case C-279/93 Finanzamt Köln-Altstadt v Schumacker [1995] ECR I-225, paragraph 30, discrimination can arise only through the application of different rules to comparable situations or the application of the same rule to different situations.
24 According to settled case-law, Article 4(1) of the Directive precludes the application of a national measure which, although formulated in neutral terms, works to the disadvantage of far more women than men, unless that measure is based on objective factors unrelated to any discrimination on grounds of sex (see, to that effect, Case C-343/92 De Weerd, née Roks, and Others v Bestuur van de Bedrijfsvereniging voor de Gezondheid, Geestelijke en Maatschappelijke Belangen and Others [1994] ECR I-571, paragraph 33, and Case C-444/93 Megner and Scheffel v Innungskrankenkasse Rheinhessen-Pfalz  [1995] ECR I-4741, paragraph 24).
32 The regression to which workers are subject when entering or returning to full-time work directly affects their pay.  They are in fact paid less than double what they would have earned had they been job-sharing. Consequently, their hourly rate of pay is reduced. Reference to the criterion of hours worked during the period of job-sharing employment, as provided for under the scheme applicable here, fails to take account either of the fact that job-sharing, as pointed out in paragraph 26 of the present judgment, is in a unique category as it does not involve a break in service, or of the fact, stated in paragraph 27 of the present judgment, that a job-sharer can acquire the same experience as a full-time worker. Furthermore, a disparity is retroactively introduced into the overall pay of employees performing the same functions so far as concerns both the quality and the quantity of the work performed.  The result of this disparity is that employees working full time but who previously job-shared are treated differently from those who have always worked on a full-time basis.
34 In such a case, provisions of the kind at issue in the main proceedings result in discrimination of female workers vis-à-vis male workers and must in principle be treated as contrary to Article 119 of the Treaty and therefore contrary to the Directive.  It would be otherwise only if the difference of treatment found to exist between the two categories of worker were justified by objective factors unrelated to any discrimination based on sex (see, along these lines, Case 170/84 Bilka v Weber von Hartz [1986] ECR 1607, paragraph 29; Case 171/88 Rinner-Kühn v FWW Spezial-Gebäudereinigung [1989] ECR 2743, paragraph 12; Case C-457/93 Kuratorium für Dialyse und Nierentransplantation v Lewark [1996] ECR I-243, paragraph 31).
35 It is for the national court, which has sole jurisdiction to assess the facts and interpret the national legislation, to determine whether and to what extent a legislative provision which, though applying independently of the sex of the worker, actually affects a greater number of women than men is justified by objective reasons unrelated to any discrimination on grounds of sex (Jenkins, paragraph 14; Bilka, paragraph 36; and Rinner-Kühn, paragraph 15).
36 However, although in preliminary-ruling proceedings it is for the national court to establish whether such objective factors exist in the particular case before it, the Court of Justice, whose task is to provide the national court with helpful answers, may provide guidance based on the documents in the main proceedings and on the written and oral observations which have been submitted to it, in order to enable the national court to give judgment (Case C-328/91 Secretary of State for Social Security v Thomas and Others [1993] ECR I-1247, paragraph 13, and Lewark, cited above, paragraph 32).
40 So far as the justification based on economic grounds is concerned, it should be noted that an employer cannot justify discrimination arising from a job-sharing scheme solely on the ground that avoidance of such discrimination would involve increased costs.
42 Community policy in this area is to encourage and, if possible, adapt working conditions to family responsibilities.  Protection of women within family life and in the course of their professional activities is, in the same way as for men, a principle which is widely regarded in the legal systems of the Member States as being the natural corollary of the equality between men and women, and which is recognised by Community law.
43 The onus is therefore on the Revenue Commissioners and the Department of Finance to establish before the Labour Court that the reference to the criterion of service, defined as the length of time actually worked, in the assessment of the incremental credit to be granted to workers who convert from job-sharing to full-time work is justified by objective factors unrelated to any discrimination on grounds of sex.  If such evidence is adduced by those authorities, the mere fact that the national legislation affects far more women than men cannot be regarded as constituting a breach of Article 119 of the Treaty and, consequently, a breach of the Directive.