WHY RESIDUARY POWER > It is humanly not possible to foresee every possible activity to assign to entries. Therefore, the residuary power is intended to take care of such matters as could not be identified at the time of the constitution-making.
SOURCE : Art. 248 read with entry 97, List I.
Article 248(1) says : “Parliament has exclusive power to make any law with respect to any matter not enumerated in the Concurrent List or State List.”
Entry 97, List I, runs as : “Any other matter not enumerated in List II or List III including any tax not mentioned in either of those Lists.
WHEN THIS POWER IS TO BE EXERCISED: Recourse to the residuary power allowed only if the matter is found to be outside the State purview.
SCOPE OF THE POWER :
Parliament’s residuary power is not to be interpreted so expansively as to whittle down the power of the State Legislatures. STATE LIST > RESIDUARY POWER .
WHY ? ”To do so would be to affect the federal principle adversely. If there is competition between an entry in List II and the residuary power of the Centre, the former may be given a broad and plentiful interpretation.
POWER TO AMEND THE CONSTITUTION CANNOT RESIDE IN RESIDUARY POWER : Kesavananda Bharathi case.
S.P. Mittal v. Union of India : A law taking over of management of Auroville by the Centre is covered by the Centre’s residuary power.
 Sable Waghire & Co. v. Union of India, AIR 1975 SC 1172 : (1975) 1 SCC 763.
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