The Centre'sopinion on this regard assumes significance as recently, a 10-party delegation from Bihar, which was led by Chief Minister Nitish Kumar, had met Prime Minister Narendra Modi demanding caste Census.

In an affidavit filed in the apex court, the government has said that caste enumeration in Socio-Economic and Caste Census (SECC) 2011 was “fraught” with mistakes and inaccuracies.

The affidavit was filed in the top court in response to a plea by Maharashtra seeking a direction to the Centre and other concerned authorities to disclose to the state the SECC 2011 raw caste data of Other Backward Classes (OBCs) which is not made available to them on “repeated demand”.

The affidavit, filed by the secretary of the Ministry of Social Justice and Empowerment, said the Centre has already issued a notification in January last year prescribing the series of information to be collected during Census 2021 and it covers many areas including the information relating to Scheduled Castes and Scheduled Tribes but does not refer to any other category of caste.

It said the exclusion of information regarding any other caste from the purview of Census is a "conscious policy decision" taken by the Central government.

It said enumeration of OBCs/BCCs (Backward Class of Citizens) has been always adjudged to be administratively “extremely complex” and even when Census of castes were taken in the pre-independence period, the data suffered in respect of completeness and accuracy.

“The issue has been examined at length in the past at different points of time. Each time, the view has consistently been that the caste Census of Backward Classes is administratively difficult and cumbersome; it has suffered and will suffer both on account of completeness and accuracy of the data, as also evident from the infirmities of the SCEE, 2011 data mentioned hereinabove making it unusable for any official purposes and cannot be mentioned as a source of information for population data in any official document,” the affidavit said.

The government said that SECC 2011 survey was not on the ‘OBC survey’ as alleged, but a comprehensive exercise to enumerate the caste status of all households in the country, as per their statement.

It said socio-economic data of households, including their “deprivations” were used to identify the poor households based on the multi-dimensional nature of poverty and used in the implementation of the anti-poverty programmes by the Central Government ministries.

It said, “the caste data has not been disclosed and has been kept with the Office of the Registrar General, India (ORGI) for various reasons, but primarily for the technical flaws that were noticed in the raw caste/tribe SECC data which makes it unusable as explained hereinafter”.

The matter came up for hearing on Thursday before a bench headed by Justice A M Khanwilkar which posted it for October 26.

In the affidavit, the government has said that so far as caste data is concerned, a caste-wise enumeration in the Census has been given up as a matter of policy from 1951 onwards and thus, the castes other than the Scheduled Castes and the Scheduled Tribes have not been enumerated in any of the Census since 1951 till today.

It said demands from various sections, including members of Parliament, for enumeration of castes in Census 2011 was received during the year 2010 and the matter was discussed in Lok Sabha and subsequently, the government referred it to a Group of Ministers (GoM) chaired by the then Union Finance Minister.

The affidavit said the Union Cabinet in 2011 decided to conduct the SECC 2011 wherein the caste of the household along with social-economic status on the identified parameters was directed to be collected.

It said as per the decision of the Cabinet, the data has been shared with the ministry of social justice and empowerment by the ORGI in a hard disk for taking the suitable decision on its use.

“Pertinently, due to several infirmities found in the aforesaid data as explained hereinafter, it was decided by the Cabinet to constitute an expert committee under the chairmanship of the then Vice-Chairman NITI Aayog Prof Arvind Panagariya,” it said.

It said other members of the committee were not named and the panel never met.

“As a result, no action has been taken on the data in the past five years,” it said.

The affidavit said as against more than 4.28 lakh castes which have been enumerated in the SECC 2011 in the state, the existing castes which are published in Maharashtra in SC, ST, and OBC categories are only 494.

“For the above referred various reasons either due to the mistakes committed by the enumerators, inherent flaws in the manner of conducting Census and several such other factors, there is no reliable or dependable castes based Census data available which can be the basis of any constitutional or statutory exercise like reservations in admission, promotion or local body elections,” the affidavit said.

The government said that the population Census is not the “ideal instrument” for the collection of details on castes and the operational difficulties are so many that there is a grave danger that the basic integrity of the Census data may be compromised and the fundamental population count itself could get distorted.