The Post Office leak of a confidential litigation document included unredacted bank details of the claimant law firm in the case, the Gazette can reveal.

Reports emerged last week that the Post Office had previously hosted on its website the confidential settlement deed from the Bates litigation.

The document, prepared in 2019 by Post Office lawyers Herbert Smith Freehills, included the full name and home address of every one of the 555 individuals involved in the group litigation.

The Post Office’s chief executive has apologised to the sub-postmasters whose names were listed and has referred itself to the information watchdog.

The document also included details of payments that the Post Office agreed to make as part of the settlement: £42m in damages, litigation funding and ATE costs, and £9.5m to claimant firm Freeths. The settlement deed posted on the Post Office website then also stated the unredacted address, sort code and account number of Freeths.

The firm has said the information disclosed by Post Office was supposed to be subject to a ‘robust’ confidentiality provision, and it is investigating what further security steps are required.

James Hartley, partner and national head of dispute resolution at Freeths, said the firm was keen to avoid anything which might delay or distract from a ‘prompt remediation’ of the harm suffered by sub-postmasters.

He added: ‘Freeths’ primary focus was to ensure that the Post Office was doing all it could to safeguard our clients’ information. This has included engaging with them, the government and the Information Commissioner’s Office, as well as acting independently to engage with online platforms that were hosting cached or archived versions of the document in order to get those removed.

‘We have also been liaising closely with our clients to address their understandable concerns in light of the media reporting of this latest incident.’

The ICO has confirmed that Post Office Limited has made it aware of an incident and it is assessing the information provided.

Christopher Head, who was falsely accused of stealing more than £80,000 from his branch near Sunderland, said the settlement deed was supposed to be kept confidential.

Writing to Post Office executives, Head said: ‘This has caused a great amount of upset, distress and anger amongst those whose data is now within the public domain.

‘There are many who hadn’t shared details with their own families and others who are extremely traumatised by this whole scandal even today and this has further impacted them.’

Nick Read, chief executive of Post Office Limited, replied to Head that this was a ‘truly terrible error and one for which at this stage I can only apologise’. The organisation, Read said, would look into what follow-up action to take and how to correct its processes.

The Post Office is understood to be in ongoing contact with Freeths over the issue and has said in a statement: 'The document in question has been removed from our website. We are investigating as an urgent priority how it came to be published. We have notified the Information Commissioner’s Office of the incident, in line with our regulatory requirements.'