Interpretation of the Legislative Lists :
For giving effect to the various items in the different lists the Courts have applied mainly the following principles :
(a) Plenary Powers: The first and foremost rule is that if legislative power is granted with respect to a subject and there are no limitations imposed on the power, then it is to be given the widest scope that its words are capable of, without, rendering another item nugatory. In the words of Gajenderagadkar, C.J.
“It is an elementary cardinal rule of interpretation that the words used in the Constitution which confer legislative power must receive the most liberal construction and if they are words of wide amplitude, they must be interpreted so as to give effect to that amplitude. A general word used in an entry … must be construed to extend to all ancillary or subsidiary matters which can fairly and reasonably be held to be included in it (Jagannath Baksh Singh v. State of U.P., AIR 1962 SC 1563).
Thus, a legislature to which a power is granted over a particular subject may make law on any aspect or on all aspects of it; it can make a retrospective law or a prospective law and it can also make law on all matters ancillary to that matter. For example, if power to collect taxes is granted to a legislature, the power not to collect taxes or the power to remit taxes shall be presumed to be included within the power to collect taxes.
(b) Harmonious Construction: Different entries in the different lists are to be interpreted in such a way that a conflict between them is avoided and each of them is given effect. It must be accepted that the Constitution does not want to create conflict and make any entry nugatory. Therefore, when there appears a conflict between two entries in the two different lists the two entries should be so interpreted, that each of them is given effect and, for that purpose the scope and meaning of one may be restricted so as to give meaning to the other also.
(c) Pith and Substance Rule: The rule of pith and substance means that where a law in reality and substance falls within an item on which the legislature which enacted that law is competent to legislate, then such law shall not become invalid merely because it incidentally touches a matter outside the competence of legislature. In a federal Constitution, as was observed by Gwyer C.J. “it must inevitably happen from time to time that legislation though purporting to deal with a subject in one list touches also upon a subject in another list, and the different provisions of the enactment may be so closely intertwined that blind adherence to a strictly verbal interpretation would result in a large number of statutes being declared invalid because the legislature enacting them may appear to have legislated in a forbidden sphere” (Prafulla Kumar v. Bank of Khulna, AIR 1947 PC 60). Therefore, where such overlapping occurs, the question must be asked, what is, “pith and substance” of the enactment in question and in which list its true nature and character is to be found. For this purpose the enactment as a whole with its object and effect must be considered. By way of illustration, acting on entry 6 of List II which reads “Public Health and Sanitation”. Rajasthan Legislature passed a law restricting the use of sound amplifiers. The law was challenged on the ground that it dealt with a matter which fell in entry 81 of List I which reads: “Post and telegraphs, telephones, wireless broadcasting and other like forms of communication”, and, therefore, the State Legislature was not competent to pass it. The Supreme Court rejected this argument on the ground that the object of the law was to prohibit unnecessary noise affecting the health of public and not to make a law on broadcasting, etc. Therefore, the pith and substance of the law was “public health” and not “broadcasting” (G. Chawla v. State of Rajasthan, AIR 1959 SC 544).
(d) Colourable Legislation: It is, in a way, a rule of interpretation almost opposite to the one discussed above. The Constitution does not allow any transgression of power by any legislature, either directly or indirectly. However, a legislature may pass a law in such a way that it gives it a colour of constitutionality while, in reality, that law aims at achieving something which the legislature could not do. Such legislation is called colourable piece of legislation and is invalid. To take an example in Kameshwar Singh v. State of Bihar, A.I.R. 1952 S.C. 252, the Bihar Land Reforms Act, 1950 provided that the unpaid rents by the tenants shall vest in the state and one half of them shall be paid back by the State to the landlord or zamindar as compensation for acquisition of unpaid rents. According to the provision in the State List under which the above law was passed, no property should be acquired without payment of compensation. The question was whether the taking of the whole unpaid rents and then returning half of them back to them who were entitled to claim, (i.e., the landlords) is a law which provides for compensatioin. The Supreme Court found that this was a colourable exercise of power of acquisition by the State legislature, because “the taking of the whole and returning a half means nothing more or less than taking of without any return and this is naked confiscation, no matter in whatever specious form it may be clothed or disguised”.
The motive of the legislature is, however, irrelevant for the application of this doctrine. Therefore, if a legislature is authorised to do a particular thing directly or indirectly, then it is totally irrelevant as to with what motives – good or bad – it did that.
These are just few guiding principles which the Courts have evolved, to resolve the disputes which may arise about the competence of law passed by Parliament or by any State Legislature.