The National Forensic Science Laboratory (NFSL), Gandhinagar, has informed the Supreme Court that the audio recordings allegedly linking former Manipur Chief Minister N. Biren Singh to the 2023 ethnic violence were found to be tampered with and unfit for scientific voice comparison, thereby preventing any opinion on the similarity or dissimilarity of the speakers.

The revelation came during the hearing of a petition seeking a court-monitored probe into the purported audio clips relating to last year’s ethnic clashes in Manipur.

A Bench of Justice Sanjay Kumar and Justice Alok Aradhe took note of the NFSL’s findings on Monday, after examining the sealed cover report. The Court directed that the final forensic report be furnished to all parties and listed the case for the next hearing on December 8.

“Four audio exhibits show evidence of modification and tampering, hence they are not original recordings and cannot be used for forensic voice comparison,” Justice Kumar read from the report. “Accordingly, no opinion on voice similarity can be provided.”

Appearing for the petitioner, Kuki Organization for Human Rights Trust, Advocate Prashant Bhushan cited a separate forensic analysis by Truth Labs, which found that a 50-minute clip (marked Y1) was unedited and showed a 93% probability match with the control sample of Singh’s voice.

Justice Kumar stated that the petitioner would receive a copy of the NFSL’s findings to enable a formal response. “We will provide you the report so you can respond to it,” he said.

The Court directed that the NFSL’s final case report dated 10.10.2025 be shared with the counsels by the Registrar.

When Bhushan noted that Truth Labs had a strong credibility record, Justice Kumar remarked, “We don’t know, because this (NFSL) is considered the premier forensic lab.”

Bhushan countered, “Yes, but it is a government lab. And your Lordships know that today when the government…” adding that the matter had been pending for over a year and a half despite containing “very damaging conversations.”

Solicitor General Tushar Mehta, representing the Union Government, emphasized that the NFSL itself confirmed tampering in the recordings. “The report shows the recordings have been altered,” he said, urging the Court to avoid further interference since “the situation in the state is now peaceful.”

Counsel for the State of Manipur said he could not follow the content of the audio, to which Bhushan replied that forensic experts possess tools to enhance clarity.

Concluding the session, the Bench directed that copies of the NFSL report be provided to both sides before the next hearing on December 8.

The matter concerns a petition by the Kuki Organisation for Human Rights Trust, seeking a court-supervised investigation into alleged recordings implicating then Chief Minister N. Biren Singh in the ethnic violence.

Earlier, in August 2025, the Supreme Court had ordered the NFSL, Gandhinagar, to conduct a detailed forensic analysis after the Guwahati Forensic Sciences Laboratory’s report failed to clarify whether the voice in the clips matched that of Singh. The NFSL was instructed to determine whether the clips had been edited and if the voice corresponded with the admitted samples, and to submit its report within six weeks.

Previously, on February 3, 2025, the Court had sought a report from the Central Forensic Science Laboratory (CFSL) regarding the same recordings. Bhushan had then relied on the Truth Labs report showing a 93% voice match, while SG Mehta had argued that the petitioner should have approached the High Court first, noting that an FIR was already registered and verification requests had been sent to social media platforms that circulated the clips.

In May 2025, the Supreme Court had expressed dissatisfaction over the delays in the forensic process, observing that “the analysis cannot go on endlessly.”

Case No. – W.P.(C) No. 702/2024
Case Title – Kuki Organization for Human Rights Trust v. Union of India