A US judge has dismissed criminal charges against Indian billionaire Gautam Adani, bringing a high-profile bribery and fraud case against one of India’s richest businessmen to an end.

In 2024, Adani was accused of allegedly paying bribes to Indian officials for high-profile renewable energy projects and misleading US investors about it. Adani and his companies have consistently denied wrongdoing.

Adani has welcomed the court order and said he accepted the decision with “humility” and “deep respect” for the judicial process.

In a 47-page order, US District Judge Nicholas Garaufis on Monday approved the Justice Department’s request to drop the charges against Adani.

However, the judge strongly criticised the way the decision was reached.

He said R Trent McCotter, principal associate deputy attorney general, had worked with Adani’s lawyers on the dismissal without consulting prosecutors and investigators who had handled the case.

Judge Garaufis described the process as “highly unusual”, saying McCotter appeared to have substituted his own judgement for that of officials directly involved in the investigation.

The BBC has not seen the official court-filed order but has reviewed a copy published by CourtListener, a US non-profit court archive. Other news organisations have also reviewed the ruling.

In May, the Justice Department asked for the charges to be dismissed, arguing that much of the alleged conduct had taken place outside the US, making the case difficult to prosecute, and that pursuing it no longer aligned with the department’s priorities.

The request came after Adani hired a new legal team led by Robert J Giuffra Jr, co-chair of the US law firm Sullivan & Cromwell and a personal lawyer to President Donald Trump. Giuffra had reportedly met Justice Department officials earlier this year to raise concerns about the case.

Judge Garaufis initially resisted the government’s request. In June, he said its explanation for abandoning the prosecution was insufficient and ordered officials to provide more information.

He also questioned whether Adani’s pledge to invest $10bn (£7.5bn) in the US and create 15,000 jobs had played a role in the decision.

Adani had announced the investment in November 2024, in a post congratulating Donald Trump on his election victory. There were later reports that Adani’s lawyers had raised the investment during discussions with the Justice Department about the case.

Adani’s lawyers said the investment was never offered in exchange for dropping the charges.

Judge Garaufis ultimately concluded that it had not influenced the Justice Department’s decision.

But he said the public could draw its own conclusions about how such discussions might affect perceptions of equal justice and the rule of law.

The judge also found that McCotter’s decision appeared to have been made without meaningful input from the prosecutors who brought the case or investigators at the FBI and Securities and Exchange Commission.

“The irregularities in the decision to dismiss the indictment are concerning,” Garaufis wrote.

The charges against Adani were dismissed with prejudice, meaning they cannot be brought again.

Adani, who never appeared in a US court during the proceedings, welcomed the ruling. “Throughout this challenging period, our faith in truth, fairness and the rule of law remained unwavering,” he wrote on X.

The criminal case is separate from other US proceedings involving Adani and his companies.

In May, Adani agreed to pay $6m and his nephew, Sagar Adani, agreed to pay $12m to settle Securities and Exchange Commission allegations related to investor disclosures, without admitting or denying wrongdoing.

Separately, Adani Enterprises, the group’s flagship company, agreed to pay $275m to settle potential civil liability over apparent violations of US sanctions on Iran.

Adani, 64, is chairman of the Adani Group, a sprawling conglomerate with interests in energy, ports, airports and other infrastructure businesses.

He is one of India’s richest men and is widely seen as close to Prime Minister Narendra Modi. Both men are from the western state of Gujarat.