One of the controversies about the Preamble is as to whether it is a part of the Constitution or not.

In the Berubari Union16 case (1960), the Supreme Court said that the Preamble shows the general purposes behind the several provisions in the Constitution, and is thus a key to the minds of the makers of the Constitution.

Further, where the terms used in any article are ambiguous or capable of more than one meaning, some assistance at interpretation may be taken from the objectives enshrined in the Preamble. Despite this recognition of the significance of the Preamble, the Supreme Court specifically opined that Preamble is not a part of the Constitution.

In the Kesavananda Bharati case17 (1973), the Supreme Court rejected the earlier opinion and held that Preamble is a part of the Constitution. It observed that the Preamble is of extreme importance and the Constitution should be read and interpreted in the light of the grand and noble vision expressed in the Preamble. In the LIC of India case18 (1995) also, the Supreme Court again held that the Preamble is an integral part of the Constitution.

Source: Indian Polity by Laxmikanth