Several perceived weaknesses of the 1947 Soulbury Constitution, however, eventually led to calls for a replacement, particularly from nationalists and the Left, the Lanka Sama Samaja Party's Colvin R. de Silva being a central figure in the movement.

[9][7] “We seek your mandate to permit the members of Parliament you elect to function simultaneously as a Constituent Assembly to draft, adopt and operate a new Constitution.

[10][2][11] The 1972 constitution paved the way for Sri Lanka to become a republic, cutting the final ties with its colonial past and British influence, and imparted a firm leftist nature to the state, allowing for the heavily socialist economic policies of the Bandaranaike government.

[7] Moreover, the drafts of the resolutions of basic constitutional principles were drawn up via a process that left the Steering and Subjects Committee with no true powers of its own:[10] The Federal Party exited the Constituent Assembly in June 1971, citing these and other reasons.

[10] Another major point of criticism has been the lack of considerations or safeguards made for the country's minority communities and their basic rights, including religion and language- the new constitution having largely done away with the few such provisions present in the previous one.