The controversy engulfing India's Tata Group has deepened after a senior ruling party lawmaker filed a complaint calling for the prosecution of its chairman Ratan Tata in connection with a fraud allegation.
The complaint by Subramanian Swamy, a former justice minister, accuses criminal investigators of having failed to follow up evidence linking Mr Tata to an allegedly corrupt telecoms transaction.
His filing, made on Friday at New Delhi's Central Bureau of Investigation Court (CBI), included a preliminary report apparently produced in 2013 by officials at India's Serious Fraud Investigation Office (SFIO), which the Financial Times has seen.
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The report states that Mr Tata and several other Tata Group executives were liable to prosecution for "cheating and dishonestly inducing delivery of property" — an offence with a maximum prison sentence of seven years.
Group holding company Tata Sons, speaking on behalf of Mr Tata and all the Tata companies involved, said that allegations about the transaction "had been thoroughly inquired into by the CBI and no evidence was found which could attribute any criminality or violation of any law or regulation".
A person close to Tata questioned the authenticity of the document, saying that the SFIO had not provided a copy of it when requested by the group. The SFIO declined to comment on the document's authenticity.
The document, addressed to the director of the SFIO, accuses Tata Group companies of having conspired to channel Rs17bn ($250m) to the real estate group Unitech, over the course of a year beginning in March 2007. Unitech allegedly used these funds to acquire a telecoms licence for Rs16.5bn in February 2008.
The document alleges that this transaction was intended to secure spectrum access through Unitech in three Indian regions for Tata Teleservices. The group's telecoms business had encountered regulatory hitches in its own application for the licence.
It goes on to accuse Tata Realty and Infrastructure, which made the payment to Unitech after allegedly receiving the funds from group holding company Tata Sons, of having cheated its shareholders by disguising it as an advance for a land purchase.
Unitech was one of eight companies that acquired 2G telecom licences in a sale process in 2008, only to have them cancelled after the Supreme Court found that they were sold at unreasonably low prices.
The licence sales were "probably . . . the biggest scam in the history of Independent India", wrote Vinod Rai, the country's former comptroller and auditor-general, whose investigation of the scandal estimated the losses to the exchequer at Rs1.76tn ($26bn).
The licence sales led to the still-ongoing corruption trial of then telecoms minister Andimuthu Raja, who denies the charges.
Mr Swamy's suit comes amid criticism of Mr Tata by Cyrus Mistry, who was abruptly replaced by Mr Tata as chairman of Tata Sons in October, less than four years after taking over from him in the role.
During a brief court appearance on Friday, Mr Swamy, a member of the Bharatiya Janata party, accused the CBI of having "tried to protect Mr Tata". Judge OP Saini agreed to consider the complaint in a further hearing on January 11. The CBI did not respond to a request for comment.
Tata Sons said the Unitech transaction was "a bona fide real estate deal that had no relation to the 2G licences", adding that it had "comprehensively addressed questions from all government agencies".
Unitech declined to comment.