JUDGMENT

CHANDRACHUD, CJI.: — The petitioners Prem Prakash and Dal Chand Anand are members of a scheduled caste. By these writ petitions under Art. 32 of the Constitution they ask for a writ of mandamus directing the respondents to appoint them against the vacancies reserved for members of Scheduled Castes and Scheduled Tribes in the Delhi Judicial Service. They also ask for a writ of prohibition to the effect that the respondents should not fill up the reserved vacancies for which they competed either by holding a fresh examination or by appointing candidates who had qualified in any previous examination. The Union of India, the Administrator of the Union Territory of Delhi and the Registrar of the Delhi High Court are respondents 1, 2 and 3 to these petitions.

2. On Sept. 26, 1979, the Registrar of the Delhi High Court published a newspaper advertisement that the Delhi High Court will hold an examination for recruitment of officers to the Delhi Judicial Service on Jan. 11, 12 and 13, 1980 in the time scale pay of Rs. 650-1200. The advertisement stated that the total number of vacancies was 16 out of which 2 were reserved for Scheduled Castes and 1 for Scheduled Tribes. In addition according to the advertisement, there were 2 carry-forward vacancies for members of Scheduled Tribes. In case of non-availability of Scheduled Tribes candidates those vacancies were liable to be transferred as reserved vacancies for Scheduled Castes candidates.

3. A competitive examination was held in pursuance of the said advertisement in accordance with the Delhi Judicial Service Rules 1970 which were framed by the Lieutenant Governor of Delhi in consultation with the High Court of Delhi. Rules 18 and 28 read thus :

"Rule 18 - The Selection Committee shall prepare a list of candidates in order of merit. Such list will be forwarded to the Administrator for filling the vacancies then existing or any vacancy that may occur within a period of one year of the preparation of the list."

"Rule 28 - Appointments made to the Service by competitive examination shall be subject to order regarding special representation in the Service for Scheduled Castes and Scheduled Tribes issued by the Central Government from time to time."

4. The Brochure on Reservation for Scheduled Castes and Scheduled Tribes in Services. (5th ed., 1978) issued by the Government of India, Dept. of Personnel and Administrative Reforms. Ministry of Home Affairs contains orders and instructions issued by the Government of India from time to time on the question of reservation of vacancies for Scheduled Castes and Scheduled Tribes candidates. The relevant paragraphs of that Brochure read as follows :-

"2. Subject to Exemptions and Exclusions referred in Chapter 3, the following reservations are in force in favour of SC and ST in filling vacancies in posts and services under the Govt. of India.

(1) Direct recruitment on an all India basis :-

(a) By open competition SC ST

(i.e. through the UPSC or by means of open competitive test held by any other authority)". 15% 7 1/2%

"4.2 The actual number of vacancies to be reserved for SC and ST in any recruitment should be determined on the basis of the points in the roster and also taking into account the reservations brought forward from the previous year the total number of reservations not exceeding normally 50% of the total number of vacancies filled in that year. However the carry forward reserved vacancies would be available together with the current reserved vacancies for utilisation even where the total number of such reserved vacancies exceed 50% of the vacancies filled in that year provided the over all representation of SC/ST in the total strength of the concerned grade or cadre is found to be inadequate i.e. the total number of SC/ST candidates in that grade has not reached the prescribed percentage of reservation for SC/ST respectively in the grade as a whole".

"9.2 Advertisement of reserved vacancies for posts filled by direct recruitment throu