Mohamud v WM Morrison Supermarkets plc [2016] UKSC 11

Tort law – Vicarious liability – Assault


Mohamud had used a petrol station kiosk and approached a member of staff with a question. The employee responded in an aggressive manner and demanded that Mohamud leave immediately. As he left the employee assaulted him. Mohamud bought an action against the supermarket, claiming that it was vicariously liable for the assault committed by one of its employees. The trial judge rejected the claim on the basis that there was not a sufficient link between the employee’s role and the assault. A subsequent appeal of the decision was rejected the Court of Appeal. Mahmoud subsequently appealed to the Supreme Court.


The basis of Mohamud’s appeal was that there should be a new test with regards to vicarious liability which weighed whether a reasonable observer would consider the employee to acting as a representative of an employer. This was an important consideration as the test had been employed for a significant amount of time prior to this challenge.


The appeal was allowed. The court held that the current ‘close connection’ test had been used in a number of cases at House of Lords/Supreme Court level and as a result of this; they did not wish to deviate dramatically from precedent. However, the court felt that a simplification of the test was more desirable. This required the consideration of the employee’s functions and whether there was a sufficient connection between the wrongful conduct and the employer. On this basis the court held that whilst it was a gross abuse of his position, it was in connection with the business by which he was employed.