The constitution vests the residuary power, i.e., the power to legislate with respect to any matter not enumerated in any one of the three lists in the union legislatures (Act. 248).
It has been left to the courts to determine finally as to whether a particular matter falls under the residuary, power or not.
It may be noted, however, that since the three lists attempt an exhaustive enumeration of all possible subjects of legislation, and courts generally have interpreted the sphere of the powers to be enumerated in a liberal way.
The scope for the application of the residuary powers has remained considerably restricted.