Why a Legislature Inquires

In one line

A House that must vote the money and hold Ministers answerable cannot do either on the Government's own account of the facts, so the power to find out for itself is not an extra power but part of the powers it already has.

In the wording a student can write in an exam: the power of a legislature to inquire is incidental to its two central functions, the power to legislate and the power to control the executive; article 75(3) makes the Council of Ministers collectively responsible to the House of the People and article 164(2) makes a State Council responsible to the Legislative Assembly, while article 266(3) provides that no moneys out of the Consolidated Fund of India shall be appropriated except in accordance with law and article 114 requires an Appropriation Act; and since responsibility and appropriation both require the House to know what has been done with the power and the money it granted, the House must be able to find out, which is what its committees exist to do and what articles 105 and 194 protect.

The two functions, and what each needs

The House legislates. To legislate on a subject it must know the subject: what the existing law does, where it fails, what the affected people say, what a technical proposal actually means. A Bill drafted in a Ministry and voted on the Minister's assurance is a Bill nobody has examined.

The House controls the executive. Article 75(3): the Council of Ministers shall be collectively responsible to the House of the People. Article 164(2): the Council of Ministers of a State shall be collectively responsible to the Legislative Assembly of the State.

Responsibility is a word about information before it is a word about consequences. A House cannot hold a Minister responsible for what it does not know. A Minister who alone decides what the House is told is not accountable to it; the House is dependent on him. That is the whole reason a legislature must be able to inquire, and it is the sentence to open an answer with.

And the House votes the money. Article 114 requires an Appropriation Act before money is withdrawn, and article 266(3) provides that no moneys out of the Consolidated Fund of India shall be appropriated except in accordance with law. Chapter 1200 works the cut motions and chapter 1010 the audit; but the point here is prior: a House that grants money and never asks what became of it has voted and not controlled.

Where the power to inquire comes from

There is no article of the Constitution saying "a House may inquire". That surprises students and it is the correct starting point.