JUDGMENT

The Judgment of the Court was delivered by

KULDIP SINGH, J.- Indian Statistical Service (the service) is governed by statutory rules called the Indian Statistical Service Rules, 1961 (the Rules). Respondents, in the appeal herein, are the members of the service. Tushar Ranjan Mohanty (Mohanty)-Respondent 1 belongs to the general category whereas Respondents 2 to 9 are members of the Scheduled Castes. Respondents 2 to 9 were promoted from Grade-IV to Grade-III in the service. They were promoted against the vacancies reserved for the Scheduled Castes and Scheduled Tribes under the instructions issued by the Government of India from time to time. Mohanty, being senior to Respondents 2 to 9 in Grade-IV, challenged their promotions before the Central Administrative Tribunal, Calcutta Bench, (the Tribunal) on the ground that under the reservation, in respect of appointments to the service by promotion, was not permitted under the Rules. The Tribunal accepted the contention of Mohanty and came to the conclusion that promotion of Respondents 2 to 9 in supersession of the claim of Mohanty was against theRules. The Tribunal, however, did not disturb the promotions already given to the respondents and directed that Mohanty be deemed to have been promoted to Grade-III from the same date when respondents were promoted and he be placed above the respondents in the seniority list of Grade-III. This appeal, by the Union of India, is against the judgment of the Tribunal.

2. We have no hesitation in holding that the Tribunal correctly interpreted the Rules as they existed on 28-11-1988 when the Tribunal delivered its judgment. These Rules were, however, amended with effect from 27-11-1972 by the notification dated 20-2-1989 and the reservation for Scheduled Castes and Scheduled Tribes was provided even in the appointments made by way of promotion. It is contended on behalf of the Union of India that in view of the amendment of the Rules with retrospective effect, the judgment of the Tribunal is liable to be set aside and the promotions of Respondents 2 to 9 to Grade-III of the service are to be upheld. Mohanty and other members of the general category have, however, challenged before us the validity of the retrospective amendment of the Rules. We shall state the grounds of challenge in the later part of the judgment.

3. Rule 8(1)(b)(i) and Rule 13 (before amendment) of the Rules are as under:

"8(1)(b) Grade-III - (i) All the vacancies in this grade shall be filled by promotion from amongst Grade-IV officers who have completed not less than four years of service on a regular basis in that grade. Promotions shall be made in the order of seniority subject to rejection of the unfit by the Controlling Authority on the advice of the Board :

Provided that if any junior officer in Grade-IV is eligible and is considered for promotion all officers senior to him in that grade shall also be considered for promotion, notwithstanding that they may not have completed four years of service on a regular basis in that grade.

13. Reservation for Scheduled Castes and Scheduled Tribes etc.- Appointments to the Service made otherwise than by promotion will be subject to orders regarding special representation in the Service for Scheduled Castes and Scheduled Tribes issued by the Government from time to time."

4. The ISS (Amendment) Rules, 1989 were framed under Article 309 of the Constitution of India and were published by the notification dated 20-2-1989. In the Rules, for Rule 13, the following rule was substituted:

"13. Reservation for Scheduled Castes and Scheduled Tribes, etc.-

Appointments to the service shall be made subject to the orders relating to reservation for SCs and STs issued by the Central Government from time to time."

Rule 1(2) of these rules provided that "they shall be deemed to have come into force on 27-11-1972."

5. Executive instructions dated 27-11-1972 issued by the Government of India provide reservation for Scheduled Castes and Scheduled Tr