“Justice S.R. Tendolkar, AIR 1958 SC 538 had postulated two conditions which must be satisfied for a classification to withstand a challenge under Article 14, namely: i) the classification should be founded on intelligible differentia which distinguishes persons or things that are grouped together from others left out of the group; and (ii) the differentia must have a rational relation or nexus to the object sought to be achieved by the statute in question. In Nallamilli Rami Reddi, (2001) 7 SCC 708 this Court had further elucidated that a challenge on the ground of denial of equal treatment will not sustain when the Legislature intends to classify persons under a well-defined class. A classification need not be scientifically perfect or logically complete and would be justified unless it is palpably arbitrary. The test to judge the validity of any classification has to be practical and pragmatic by looking beyond the classification to the purpose or object of the law and the circumstances which had prevailed when the law was passed and which had necessitated passing of that law. Not only this, there is a presumption as to constitutional validity of an enactment predicated on the belief that the Legislature understands and correctly appreciates the need of its own people and is free to recognize degrees of harm and may confine its restriction to only those cases where the need is deemed to be the clearest. The hardship that may result from the classification cannot be the basis for determining the validity of any statute. This requires distinguishing between under-inclusiveness and over-inclusiveness. The former classification does not confer the same benefit or place the same burden on others who are similarly situated whereas over-inclusiveness includes not only those who are similarly situated with respect to the purpose but others who are not so situated as well. The latter is frowned upon but the former may pass the judicial test for the Courts do excercize tolerance to under-inclusiveness unless it is clear that there is no fair reason for the law which would not require with equal force its extension to those whom it leaves untouched.”
– Hon’ble Justice Sanjiv Khanna, Ram Krishan Grover v. Union of India, [Civil Appeal No. 8597 of 2019].