One of the whistleblowers behind the Panorama programme on Labour’s antisemitism has claimed that a referral by Jeremy Corbyn’s team resulted in him being the subject of a criminal investigation.

Sam Matthews, Labour’s former head of governance and legal, was one of seven whistleblowers and the BBC journalist John Ware who received a formal apology from the party last week for “untrue and defamatory” comments made against them after the programme was aired last July.

The Sunday Times has reported that Mr Matthews, 28, was the subject of a criminal investigation and received a letter summoning him for an interview under caution shortly before Mr Corbyn’s resignation.

He had been reported to the Information Commissioner’s Office, which can investigate criminal breaches and institute prosecutions.

The accusation was that he breached the Data Protection Act by improperly accessing and leaking information to the media, allegedly passing on sensitive data on around 30 people. The stories mostly focused on the party’s alleged mishandling of antisemitism complaints.

In February, Mr Matthews was told by the ICO’s criminal investigations team that he was “suspected of a criminal offence” and cautioned. But the investigation was dropped after he challenged its basis. The ICO later admitted it had no evidence that he had unlawfully obtained personal data.

Mr Matthews said he was glad the authority had concluded that there was “no merit in the Labour Party’s complaint, made under its previous leader”.

With the party under new management, he hoped a line had been drawn under “the Labour Party’s...campaign to bully and victimise whistleblowers”.