The Supreme Court on Tuesday said results of the Election Commission's ongoing 'special intensive revision' of the Bihar voter list can be set aside as late as September, two months before the Assembly election is expected in the eastern state, if illegality is proven in the process.

The assurance was provided in response to arguments about the authority of the Election Commission, which sought 11 documents from Bihar residents to re-verify their voter status.

The poll body had earlier stated that voters cannot use commonly accepted government IDs, such as the Aadhaar (and its own identity card), to establish citizenship and reverify themselves, as these are only proof of identity.

It also noted that such documents are easier to forge than those on its list.

When the top court remarked that the poll body was right in stating that an Aadhaar card is not definite proof of citizenship, the petitioners argued that such was not their case.

They said their case was about the illegality of the process and questions over the poll body's jurisdiction to determine citizenship.

Appearing for Rashtriya Janata Dal MP Manoj Kumar Jha, senior advocate Abhishek Singhvi said the question was 'does the EC have the right to establish citizenship in the first place?'

The right to grant (or revoke) citizenship lies with the Home Ministry, he pointed out.

"They (i.e., the Election Commission) say that Aadhaar is not enough to determine citizenship... but they don't have the authority to decide citizenship..." Singhvi said.

"The court had said they only need to ascertain identity ... you cannot have a system where citizenship is doubted for five crore people. The presumption is they are valid citizens unless they (i.e., the government) removes them. The EC was never intended as 'policeman of citizenship'."

In response, Justice Surya Kant then pointed out that while the government is responsible for citizenship, "... exclusion of non-citizens from electoral rolls is within the remit of the EC."

"Yes! (If I am not a citizen) I can be stopped (from appearing on the voter list) till I get citizenship. But if I am already on the electoral roll... then how can the EC determine?" Mr Singhvi replied.

It was then that the court said, "If they declare five crore invalid... we are sitting here."

While not a verdict on the Election Commission's contentious re-verification of nearly eight crore voters months before an election, the remarks are a big positive note for opposition leaders and activists who have challenged the exercise's constitutional premise and legal validity.