The main legal point established in the judgment is the need for reasonable classification based on job requirements and the justification for preferential treatment of graduates over non-graduates.

1. Petitioner holds a certificate for having passed the Trade Test (Electrician), after completing S.S.L.C. He commenced service in 1952 as a Telephone Operator. He was promoted as a First Grade Overseer in 1974 and was further promoted as Assistant Engineer under Ext.P1 dated 11-6-1984. Ext.P2 is the Special Rules for the post of Assistant Engineer (Electrical) issued by the State Government in G.O.Ms.330/65/PW dated 29-11-1965. Notes 1 to 3 were added to the method of appointment by promulgation of G.O.(P) 80/74/PW dated 25-5-1974. The effect of that Note in so far as it concerned the petitioner was to prescribe a ratio of 3:2 between diploma-holders and certificate holders for promotion as Junior Engineers (since redesignated as Assistant Engineers (Ele.)). A final seniority list of First Grade Draftsmen/ Overseers, to which category the petitioner belonged, was published in Ext.P3 proceedings dated 9-12-1983. The seniority list attached thereto is Ext.P3(a). Petitioner was Sl. No.39 and the fourth respondent was S1.No.42 in that list. In Ext.P4 G.O.Ms.10/80/PI & E dated 18-1-1980, Government ordered regularisation of provisional employees under R.18(a) of the Kerala State and Subordinate Services Rules and such regularisation would not affect the seniority of the petitioner. Government, however, issued Ext.P5 order, G.O.Rt.41/85/PW & PD dated 2-5-1985, whereby 60 provisional employees in the Electrical Wing were given retrospective regularisation with effect from 17-1-1974. A list of provisional employees, whose services were regularised, accompanied that order. Still later, the Chief Engineer published Ext.P6 inducting the provisional employees, whose services were regularised in Exts.P4 and P5, into regular establishment. In that list, the name of the petitioner was included as S1.No.41 with 12-8-1974 as the assigned date of promotion. He had, in the meantime, been promoted as Assistant Engineer in 1984. The Chief Engineer published Ext.P7 final seniority list of Assistant Engineers as on 1-6-1986. The name of the petitioner was not included in that list, because the date of his promotion was assigned to another employee. Petitioner filed Ext.P8 representation, requesting for a further scrutiny of Ext.P7 list and not to revert him while allowing his juniors in the category of First Grade Overseers to continue as Assistant Executive Engineers. The fourth respondent, petitioner and another filed O.P.No.5057 of 1987, assailing Ext.P7 and the possible reversion. That Original Petition was dismissed as withdrawn, since there was likely to be conflict of interest between the petitioners. It was thereafter that the petitioner filed the present Original Petition. In the meantime, the Chief Engineer issued Ext.P10 order dated 26-6-1987, reverting the petitioner as First Grade Overseer (Electrical) while retaining the fourth respondent, who was his junior, in the higher post, because he was a diplomat. Petitioner submits that the provisional employees could not have been regularised in service in contravention of the provisions of R.18(a) of the Kerala State and Subordinate Services Rules. He therefore assails Ext.P5 order and Ext.P7 final list. He also submits that in spite of his seniority and the completion of the requisite period of experience, he was reverted only because he was a certificate-holder and to provide for, his junior, the fourth respondent, who was a diploma-holder. This was because of the provisions contained in the note, which was added to R.2 of Ext.P2 rules by G.O.(P) 80/74/PW dated 25-5-1974. He therefore assails Note to R.2 of Ext.P2 rules as violative of Art.14 and 16 of the Constitution of India. He naturally challenges Exts.P6 and P6 (a) seniority lists, which upset his right under Ext.P3 and P3(a) and the consequential reversion order, Ext.P10.

2. Petitioner relies on a number of decisions of the Supreme Court and this court in support of his submission, that the classification of eligible em