JUDGMENT

VENKATARAMIAH, J.:— People belonging to the Scheduled Castes and the Scheduled Tribes and to other weaker sections of society in India are the zealously protected children of the Indian Constitution. Article 46 of the Constitution provides that the State shall promote with special care the educational and economic interests of the weaker sections of the people, and, in particular, of the Scheduled Castes and the Scheduled Tribes, and shall protect them from social injustice and all forms of exploitation. While clause (1) of Article 15 of the Constitution provides that the State shall not discriminate against any citizen on grounds only of religion, race, caste, sex, place of birth or any of them, clause (4) of that Article provides that nothing in the said Article or in clause (2) of Article 29 of the Constitution shall prevent the State from making any special provision for the advancement of any socially and educationally backward classes of citizens or for the Scheduled Castes and the Scheduled Tribes. Similarly, while clause (1) of Article 16 of the Constitution provides that there shall be equality of opportunity for all citizens in matters relating to employment or appointment to any office under the State and clause (2) of the said Article provides that no citizen shall, on grounds only of religion, race, caste, sex, descent, place of birth, residence or any of them, be ineligible for, or discriminated against in respect of any employment or office under the State, clause 140 (4) of the said Article provides that nothing in that Article shall prevent the State from making any provision for the reservation of appointments or posts in favour of any backward class of citizens which, in the opinion of the State, is not adequately represented in the services under the State. Article 330 and Article 332 of the Constitution provide for reservation of seats for the Scheduled Castes and the Scheduled Tribes in the Lok Sabha and in the Legislative Assemblies of the States till such period as is provided in Article 334 of the Constitution. Article 335 of the Constitution, which is relevant for purposes of this case, provides that the claims of the members of the Scheduled Castes and the Scheduled Tribes shall be taken into consideration, consistently with the maintenance of efficiency of administration, in the making of appointments to services and posts in connection with the affairs of the Union or of a State.

2. The present case is, however, one in which a concession which had been extended to the employees belonging to the Scheduled Castes and the Scheduled Tribes by way of reservation of vacancies at the stage of promotion has been withdrawn in a rather concealed way. Petitioners 1 and 2 in this Writ Petition are the P & T Scheduled Caste/Tribe Employees Welfare Association (Regd), Delhi and the Federation of All India Scheduled Castes & Scheduled Tribes, Employees P & T Department, New Delhi and petitioner 3 is an employee in the Posts & Telegraphs Department. By the letter bearing No. 27/2/71-Estt. (SCT) dated 27-11-1972 issued by the Department of Personnel, the Government communicated its policy regarding the reservations for the Scheduled Castes and the Scheduled Tribes in posts filled by promotion/promotions on the basis of seniority subject to fitness. The said policy was adopted by the Government in supersession of the orders contained in an earlier Government Order dated 11-7-1968. Under the said policy a reservation of 15 per cent of vacancies was made for the Scheduled Castes and 7-1/2 per cent for the Scheduled Tribes wherever promotions were to be made on the basis of seniority subject to fitness, in appointments to all Class I, Class II, Class III and Class IV posts in grades or services in which the element of direct recruitment, if any, did not exceed 50 per cent. In order to implement the above reservation the Government directed the appointing authorities to maintain a separate 40-point roster to det