The burden of proof is on the party attacking the rule to show a clear transgression of constitutional principles, and the classification must be based on an intelligible rationale having a nexus with the object sought to be achieved.

Degree holders and Diploma holders in the cadre of Asst: Executive Engineers in Kerala State Road Transport Corporation (for short'the Corporation') have been classified into two categories for the purpose of further promotion to the cadre of Executive Engineers. The relevant clause in the Regulations formulated by the Corporation which made the aforesaid classification has been assailed in this Original Petition filed by two Diploma holders.

2. The petitioners and the fourth respondent are now Asst. Executive Engineers in the Corporation. Their next promotion is to the cadre of Executive Engineers. While petitioners are diploma holders the 4th respondent is a graduate in Civil Engineering. Clause 5(1) of the K.S.R.T.C. Civil Engineering Staff (Method of appointment) Regulations (for short 'the regulations') reads thus:

Executive Engineer

Method of Recruitment

(1) By selection from among Asst. Executive Engineers with minimum 3 years experience in case of Degree holders and 5 years in case of Diploma holders.

According to the petitioners, the requirement that diploma holders should have 5 years experience as Asst. Executive Engineers for entitlement to promotion to the next cadre is discriminatory and hence violative of Articles 14 and 16 of the Constitution. Learned counsel for the petitioners contended that when once two categories have been fused into one cadre, a dichotomy as between them subsequently, even if it is for further promotion, is impermissible, as it would offend Articles 14 and 16 of the Constitution. Learned counsel also contended that the burden is on the authority which formulated the rule to substantiate that the classification is not discriminatory or that the classification has a nexus with the object sought to be achieved.

3. Classification as such is not altogether forbidden by Arts.14 or 16 of the Constitution. The of repeated rule is that the classification must be based on an intelligible rationale having a nexus with the object sought to be achieved. In the impugned Regulations the classification is apparent as between degree holders and diploma holders. One cannot contend that a diploma holder stands on a par with a degree holder from academic standpoint. A degree in one subject is certainly weightier than diploma in that subject; although, perhaps, a diploma holder may successfully carry out the same amount of work with the same amount of skill as what a degree holder is able to perform. But it is unreasonable to compel any one to treat a degree holder and a diploma holder alike without any rider whatsoever. Even if diploma holders and degree holders were treated alike at a particular stage or cadre, the authority concerned is not under any disability to retain the integration unbroken at least for higher echelons in the same service. In the impugned Regulations what is stipulated is that diploma holder must acquire a larger length of service to qualify himself to be promoted to the next cadre while degree holder need acquire a lesser length of service. Such a stipulation, even on the face of it, is only consistent with the ostensible difference between a degree and a diploma in the same subject.

4. A plethora of case law has developed on this aspect. Though it is. Unnecessary to refer to all of them pr even a good number of them, it would be helpful to advert to the decision which ai constitution Bench of the Supreme Court (State of J & K v. Triloki Nath Khosa (1974 S.C.1) has pronounced. The question posed before the Supreme court then was this: If persons drawn from different sources are integrated into once class, can they be classified for purposes of promotion on the basis of their educational qualifications? There also the classification made was as between diploma holders and degree holders in Engineering. A larger length of service was prescribed for diploma holders for promotion to the next cadre. The diploma holders challenged the Rule, which put them under the aforesaid disabilit