The amended law seeks to grant citizenship to non-Muslim migrants belonging to the Hindu, Sikh, Buddhist, Christian, Jain and Parsi communities who came to the country from Pakistan, Bangladesh and Afghanistan on or before December 31, 2014 due to religious persecution.

The affidavit filed by B.C. Joshi, Director in Ministry of Home Affairs, said that CAA is a narrowly-tailored legislation seeking to address the specific problem which awaited a solution since several decades, and it does not affect the legal, democratic or secular rights of any Indian citizen.

The Centre said that equal protection of the laws guaranteed by Article 14 of the Constitution does not mean that all laws must be general in character and universal in application and that the legislature no longer has the power of distinguishing and classifying persons or things for the purposes of legislation.

"It is humbly submitted that the only requirement prior to making a particular classification or a special legislation (as is in the CAA) is that the legislative classification must not be based on any arbitrary classification and should be based on an intelligible differentia having a reasonable relation to the object which the legislature seeks to attain," it said.

The Centre insisted unlike the particular neighbouring countries, "India is a constitutionally secular country and further has a large population of persons belonging to the classified communities already residing as Indian citizens".

It contended that the CAA is a "benign piece" of legislation which seeks to provide a relaxation, in the nature of an amnesty, to specific communities from the specified countries with a clear cut-off date.

After considering the totality of factors, including factors of international geopolitics, the demographic profile of nations surrounding the particular neighbouring countries, the situation of or the presence of other persons of classified communities in other nations surrounding the neighbouring classified countries and the presence of state religions/theocratic regimes in other countries surrounding the neighbouring classified countries, the Centre said it "makes it amply clear that India represents the sole rational and logically feasible place to seek shelter for the said communities".

The Centre's affidavit said: "It is submitted that constitutional morality is not an unruly horse and cannot become an independent basis for challenging the constitutionality of validly enacted legislations."

It maintained that the CAA, 2019 does not confer any arbitrary or unguided powers upon the executive. "Under Section 6B(1) the Central Government or a specified authority would grant citizenship only in a manner where certain conditions & restrictions would be satisfied by the applicant. Appropriate rules under Section 6B are being framed to clearly lay down these conditions, restrictions and manner of grant of citizenship."

"It is submitted that the CAA is a specific amendment which seeks to tackle a specific problem prevalent in the specified countries i.e. persecution on the ground of religion in light of the undisputable theocratic constitutional position in the specified countries, the systematic functioning of such States and the perception of fear that may be prevalent amongst minorities as per the de facto situation in the said countries."

Addressing the issue of citizenship for Rohingyas, the Centre said that thousands of Rohingyas have come into India, mainly through Bangladesh, in search of better economic opportunities. "It is submitted that the Rohingyas are not on the same footing as the religiously persecuted minorities who have fled into India from the particular neighbouring countries," said the Centre.

Seeking to keep out CAA out of judicial review, it said: "It is submitted that by the very nature of the question regarding citizenship of the country and issues pertaining thereto, the said subject matter may not be within the scope of judicial review and may not be justiciable."