(a)

In support of their claim, the applicants state that the Commission has infringed Article 5 (3) of the Staff Regulations and contravened the principle of equal pay for equal work, in so far as it pays less to the applicants than to other officials employed by the same insutution or by other institutions who perform comparable duties. Even if it is conceded that the Commission is right in its assertion that the provision in question, according to which “Identical conditions of recruitment and service career shall apply to all officials belonging to the same category or the same service”, is not intended to guarantee the same remuneration for officials who perform comparable duties, it is fundamentally incontestable that the principle of equal treatment must be taken into account in the rules governing the staff of the Communities. As the Court has emphasized on several occasions, inter alia in the Boursin ( 2 ) case, a particular aim of the principle embodies in Article 5 of the Staff Regulations that an official's grade must correspond to the duties performed by him is to avoid inequality of treatment as between officials to whom duties of a legally comparable nature have been assigned. However, contrary to the view held by the applicants, it is not possible to treat every case of different treatment as a breach of that prohibition of discrimination. On the contrary, as the Court has always made clear, a breach of the principle of equal treatment is only to be presumed when the difference of treatment is not objectively justified. A difference of treatment may however, notwithstanding a similar description for a given activity, be justified in particular on grounds relating to the quality and quantity of the work done. Accordingly, it is inappropriate to complain about the fact that operators of interpretation equipment who, as in the case of those employed by the Commission in Luxembourg, form a small team of six officials and therefore must, if the need arises, deputize for one another are in a better situation as regards salary than some operators employed by the Commission in Brussels where at least 22 officials are available to carry out the duties required. The comparison made by the applicants with the technicians working for the Parliament is also to be seen in that light. In this case also it is evident that the different scope of the duties, particularly in view of the amount of interpretation equipment involved, may justify different treatment of the technicians. Moreover, the different demands of the post are also reflected in the qualifications required for it. Thus in its Notice of Competition No COM/C/4/78 for the drawing up of a reserve list for clerical assistants the Commission merely required knowledge of radio-technology whilst the Parliament, in an equivalent Notice of Open Competition (PE 75/C — Official Journal 1979, C 249 of 20. 10. 1978, p. 8) for clerical officers (technicians) in Grade C 3 required a technical diploma in radio-electńcity. Finally, it likewise does not follow from the comparison drawn by the applicants between their own position and that of officials of the same branch in Brussels that the Commission has breached the principle of equal pay for equal work by according the latter a higher classification. In this connection it may still be an open question whether, although their duties are similarly described, those officials actually undertake work which is more demanding since in any case a different classification on account of differing seniority and age and the resulting experience is objectively justified. A glance at the list produced by the Commission of the staff employed by it as operators of interpretation equipment clearly shows that the Commission took those criteria into account. Thus the average seniority of the technicians in Grade C 5 is five years, that of those in Grade C 4 is six years, that of the C 2 officials is 18 years and that of the C 1 officials is 18 Vi years. To take another example, the age of the C 5 technicians is under 30 years, whilst the C 1 officials are over 40 years old. If the officials with scant experience of life and the service were from the outset to be accorded the same classification as older officials entrusted with comparable duties, advancement within the same category would be impossible.