Thus, while US prosecutors may have indicted Adani Group chairman, Gautam Adani, his nephew Sagar Adani and others in an alleged bribery case involving Indian states, CBI can investigate the matter only if it is asked to be the Centre.

To be sure, the Centre has done this in the past –– for instance, in the 2016 Rolls Royce case, and the 2016 Embraer one.

Following revelations on the prosecution of Adani by the US Department of Justice –– while the alleged bribery happened outside the US, the fact that this was not disclosed in a US fund raising exercise by the conglomerate is the grounds for the case –– there have been demands by opposition parties for a probe by Indian agencies.

CBI operates under the ambit of Delhi Special Police Establishment (DSPE) act. As per Section 3 of the Act, it is authorised to conduct investigations under those sections of law, which are notified by the central government from time to time. The state governments have to give consent to the premier agency under Section 6 of DSPE for carrying out probes in their jurisdiction. Another way for CBI to take up cases is on the basis of orders from the Supreme Court, high courts or Lokpal.

It can take up suo motu corruption cases only in the Union territories.

A former CBI joint director who asked not to be identified said “CBI is not directly empowered to probe” cases such as the Adani one.

Read more: ‘Will study US indictment report, act on it’: CM Chandrababu Naidu on bribery charges against Adani, Jagan Reddy

“The process says the Centre has to refer such an international probe to CBI. But for that to happen, we have to see whether US department of Justice (DoJ), or the Federal Bureau of Investigation (FBI) approached the Indian government seeking information,” said this former officer.

Another officer, who asked not to be named, said, “CBI cannot even start an enquiry without the consent of the Centre in a matter which involves international boundaries.”

Within India, CBI is already struggling to investigate corruption cases due to the restriction imposed on it under the DSPE act, which states that it needs states’ consent. Karnataka became the eighth state last month to withdraw general consent under Section 6 of the DSPE act –– after Punjab, Jharkhand, Kerala, West Bengal, Telangana, Meghalaya, and Tamil Nadu.

Congress chief Mallikarjun Kharge on Thursday demanded a comprehensive Joint Parliamentary Committee probe into the Adani matter while CPI(M) has demanded a CBI probe into the allegations.

US prosecutors have said the Adani Group paid $265 million in bribes to Indian government officials to secure contracts with state electricity distribution companies between 2021-2023. The Adani Group has called the allegations baseless.

In the $210 million Embraer deal, CBI filed a charge sheet last year naming Arvind Khanna, son of deceased arms dealer Vipin Khanna, and businessman Anoop Kumar Gupta. The central probe agency was investigating Embraer for allegedly using middleman Vipin Khanna for securing the contract for supplying three EMB-145 aircrafts to Defence Research & Development Organisation (DRDO). The agency alleged that in lieu of facilitating the deal, the firm paid $ 5.76 million to Vipin Khanna through Singapore-based firm Interdev Pte. Ltd. in 2009 and this money was used by him to influence officials of the defence ministry. The case is pending in court.

Meanwhile, CBI started a preliminary enquiry (PE) and later filed a first information report (FIR) last year, naming British arms dealer Sudhir Choudhrie, his son Bhanu Choudhrie, companies Rolls Royce PLC, British Aerospace Systems and others over alleged irregularities in Hindustan Aeronautics Limited (HAL)’s procurement of 24 Hawk 115 Advance Jet Trainer aircraft and licence manufacturing of 42 additional aircraft between 2003 and 2012. The probe agency is currently investigating the matter.