In a two-page order, the court said that ownership of immovable property in India does not, by itself, establish Indian citizenship.
Land ownership not proof of citizenship
"A foreign national can buy a property in India. Merely because a foreign national buys an immovable property in India ipso facto does not make such purchaser an Indian citizen," the court observed.
The remarks came after Mollah's relative moved the high court challenging his detention. Mollah is currently lodged in a detention centre.
Court seeks conclusive citizenship documents
Appearing for the petitioner, Mollah's counsel argued that the detainee is an Indian national. However, the state government submitted that Mollah had allegedly confessed to being a foreign national.
During the hearing, the court asked the petitioner to produce documents proving his Indian citizenship.
The petitioner's lawyer admitted that none of the documents filed with the petition conclusively established Mollah's citizenship, except land records.
"In response to such query of the court, learned advocate appearing for the petitioner submits that no document annexed to the writ petition conclusively establishes the Indian citizenship of the detainee, excepting the land records," the order said.
Rejecting that contention, the court observed, "Land records, which the petitioner refers to again, are not a document of proof of Indian citizenship."
The court has granted the petitioner another opportunity to submit documentary proof of Mollah's citizenship. The matter will be heard again on July 20.
Passport clarification echoes court's observation
The High Court's remarks come weeks after the Centre clarified that an Indian passport is also not conclusive proof of citizenship.
Government sources had told NDTV that passports have never been treated as definitive evidence of Indian citizenship because, under certain legal provisions, they may also be issued to non-citizens.
The clarification was in line with a 2013 Bombay High Court judgment, which held that possession of a passport alone cannot conclusively establish Indian citizenship.
Citizenship debate amid NRC buzz in Bengal
The ruling also comes against the backdrop of an intensifying political debate over citizenship in West Bengal.
Earlier, West Bengal Chief Minister Suvendu Adhikari indicated that the state could see an Assam-style National Register of Citizens (NRC).
He also promised a Uniform Civil Code and stricter laws against alleged land jihad, love jihad and forced religious conversion.
The Calcutta High Court's latest observations are likely to add further legal and political significance to the ongoing debate over citizenship documentation and verification in the state.