Supermarket chain Morrisons will try for a second time to overturn a judgment in favour of more than 5,000 staff members who had personal data stolen, in a long-running dispute over whether employers can be held vicariously liable for a single rogue employee’s actions.

The Supreme Court is to hear Various Claimants v Wm Morrisons Supermarket, a case in which 5,518 claimants are seeking compensation.

The claim followed a security breach in 2014 when former employee Andrew Skelton, then a senior internal auditor, leaked payroll data. Skelton was found guilty of fraud, securing unauthorised access to computer material and disclosing personal data. He was jailed for eight years in 2015.

Former and current employees claimed that the leak exposed them to the risk of identity theft and financial loss, and that Morrisons was responsible for breaches of privacy, confidence and data protection laws.

The High Court in 2017 found Morrisons to be vicariously liable; a finding agreed by the Court of Appeal in October last year

Nick McAleenan, partner at data privacy law firm JMW Solicitors, representing the claimants, said: ’It cannot be right that there should be no legal recourse where employee information is handed in good faith to one of the largest companies in the UK and then leaked on such a large scale. This was a very serious data breach which affected more than 100,000 Morrisons employees - they were obliged to hand over sensitive personal and financial information and had every right to expect it to remain confidential.’

Commenting on the appeal decision, Tim Smith, head of technology, media and telecoms and cyber at national firm BLM, said: ’Given the wealth of case law dealing with vicarious liability and a clear direction of travel to make employers liable, there was a real prospect that the Supreme Court would take the view that this area of law was established and that it did not need to review the decision.

‘However, whilst this means that Morrisons gets another chance to make its case, it may face an uphill struggle having lost in the High Court and Court of Appeal and with a body of case law that seems to go against it. Nonetheless many businesses and their insurers will be hoping that the appeal succeeds.’

International firm DWF, which is representing Morrisons, has been contacted for comment.