Doctrine of unreasonableness - Doctrine of proportionaliTY

“The departmental proceeding is a quasi-judicial one. Although the provisions of the evidence act are not applicable in the said proceeding, principles of natural justice are required to be complied with. The courts exercising power of judicial review are entitled to consider as to whether while inferring commission of misconduct on the part of a delinquent officer relevant piece of evidence has been taken into consideration and irrelevant facts have been excluded therefrom. Inference on facts must be based on evidence which meet the requirements of legal principles. The Tribunal was, thus, entitled to arrive at its own conclusion on the premise that the evidence adduced by the Department, even if it is taken on its face value to be correct in its entirety, meet the requirements of burden of proof, namely, preponderance of probability. If on such evidences, the test of the doctrine of proportionality has not been satisfied, the Tribunal was within its domain to interfere. We must place on record that the doctrine of unreasonableness is giving way to the doctrine of proportionality.

Moni Shankar v. Union of India 2008 3 SCC 484 (SCC p. 492, para 17)