ORDER

(The petitioners and respondents 4, 5 and 6 are members of the Punjab Service of Engineers (Class I) (the Service) in the Irrigation Department of the State of Punjab. The respondents are members of the Scheduled Castes whereas the petitioners belong to the general category. The conditions of service of the members of the Service are governed by the Rules called the Punjab Service of Engineers Class I P. W. D.(I. B.) Rules, 1964 (the Rules). The Punjab Government by the instructions dated May 4, 1974 provided reservations for the Scheduled Castes and Backward Classes in promotions to and within Class I and II services under the State Government. It was laid down under the said instructions that 16 percent of the posts to be filled by promotion were to be reserved for members of the Scheduled Castes and Backward Classes (14 percent for the Scheduled Caste and 2 per cent for the Backward Classes) subject to the conditions that the persons to be considered must possess the minimum necesary qualifications and they should have satisfactory record of service . the instructions further provided as under :

"(1) In a lot of 100 vacancies occurring from time to time, those falling at serial numbers mentioned below should be treated as reserved for the members of Scheduled Castes;

1. 7, 15, 22, 30, 37, 44, 51, 58, 65, 72, 80, 87, 91 and so on. Vacancies falling at serial numbers 26 and 76 should be treated as reserved for the members of Backward Classes.

(ii) The reservation prescribed shall be given effect in accordance with a roster to be maintained in each Department. The roster will be implemented in the form of a running account from year to year."

Rule 9 of the Rules which provides for promotion within the service reads as under:

"Promotion within service :(

(1) Subject to the provisions of sub-rules 2 and 3 members of the Service shall be eligible for promotion to any of the posts in the service, namely , Executive Engineers, Superintending Engineers and Chief Engineers :

Provided that a Member of the service in whose case the qualifications mentioned in clause (a) of rule 6 have been waived, shall not be eligible for promotion to the post of Superintending Engineer or above till he has acquired the necessary qualification.

Explanation :( Once an officer has been appointed a member of the Service, his promotion within it from one rank to another shall be regarded as promotion within the same cadre.

(2) Promotions shall be made by selection on the basis of merit and suitability in all respects and no member of the Service shall have any claim to such promotion as a matter of right or mere seniority.

(3) A member of the Service shall not be eligible for promotion to the rank of -

(a) Executive Engineer unless he has rendered five years service as an Assistant Executive Engineer;

Provided that an officer who has rendered six years or more service as an Assistant Executive Engineer shall unless he is considered unsuitable for promotion, be given preference for such promotion over an eligible Class II Officer;

(b) Superintending Engineer, unless he has rendered seven years service as an Executive Engineer;

(c) Chief Engineer, unless he has rendered three years service as Superintending Engineer;

Provided that , if it appears to be necessary to promote an officer in public interest, the Government may, for reasons to be recorded in writing, either generally for a specified period or in any individual case reduce the period specified in clauses (a), (b) and (c) to such extent as it may deem proper."

It is stated in writ petition that the petitioners are at serial Nos. 19, 23, 26, 29, 30, 31, 34 and 38 of the seniority list of the service whereas the respondents are at serial Nos. 46, 140, and 152 . Respondent-Rattan Singh was promoted to the rank of Chief Engineer against the post reserved for the Scheduled Castes by superseding 36 senior colleagues including the petitioners. Similarly, respondents Surjit Singh and Om Prakash were promoted as Super