The problem is to decide whether this distinction amounts to discrimination of a kind not permitted by article 26 of the Covenant. has failed to substantiate, for purposes of admissibility, that the distinction was not objective or how it was arbitrary or unreasonable. Therefore, the Committee concludes that the communication is inadmissible under article 2 of the Optional Protocol. To answer this question it is necessary to consider whether the aim of the differentiation is to achieve a purpose which is legitimate under the Covenant and whether the criteria for differentiation are reasonable and objective. The State party claims that the differentiation is based on reasonable grounds; the author, on the other hand, claims that the basis of differentiation is unreasonable and discriminatory. The author's claim falls within the scope of article 26 of the Covenant and raises a point of substance which cannot be determined without consideration of the issues outlined above, that is to say, without consideration of the merits of the case. The claim has thus been substantiated for purposes of admissibility. 9. The Human Rights Committee therefore decides: (a) That inadmissible; the communication is (b) That this decision shall be communicated to the author and, for information, to the State party. Ideally, where the issues raised by the author involve claims of discrimination of this kind, and where there are no complex questions concerning admissibility (other than those concerning the substantiation of the claim of discrimination), the Committee should be able to call for submissions to enable it to deal with admissibility and merits in one step. However, that is not the procedure provided for in the rules and was not adopted for this case. In the absence of such a procedure, some cases such as this one are found to be inadmissible, because the Committee is of the view that the claim of discrimination has not been made out. This separate opinion emphasises that a claim of discrimination which raises an issue of substance which requires consideration on the merits should be found admissible. APPENDIX Individual opinion submitted by Mrs. Elizabeth Evatt, Ms. Cecilia Medina Quiroga, Mr. Francisco José Aguilar Urbina, Mr. Prafullachandra Natwarlal Bhagwati and Mr. Andreas Mavrommatis pursuant to rule 94, paragraph 3, of the Committee’s rules of procedure, concerning the Committee’s decision on communication No. 608/1995, Franz Nahlik v. Austria The author of this communication is challenging a distinction made between those employees of the Social Insurance Board who retired before January 1992 and those who retire after that date. The pension entitlements for each group are based on the current monthly salary of employees. Under a collective agreement between the Social Insurance Board in Salzburg and its employees, the salary of current employees can be supplemented by regular payments which do not form part of the monthly salary [para 2.2.]. By this means, it is possible to benefit current employees by payments which do not affect existing pensions in any way, but yet can be taken into account in calculating the pension for employees who retire on or after 1 January 1992. A further reason to have declared this particular case admissible is the fact that neither the State nor the author were given notice that the Committee would decide on admissibility having regard to the substance of the matter. The author himself pointed to the fact that the State's observations to his communication related mainly to the merits and were irrelevant for admissibility (paragraph 7.1). A finding that the communication is inadmissible would deny to the author an opportunity to respond to the submission of the State party. For these reasons we consider the communication admissible. 12