Mr AM Mohamud v WM Morrison Supermarkets plc  UKSC 11
When Mr Mohamud was violently assaulted by a petrol pump assistant employed by Morrisons, he argued that the supermarket should be vicariously liable for his attacker’s actions.
The claim failed at trial and before the Court of Appeal. The Supreme Court had to consider how the law in this area has developed and whether it was in need of significant change.
Mr Mohamud went to a Morrisons’ petrol station in Birmingham. He asked whether the garage could print off some images from a USB stick.
Amjid Khan worked behind the counter. He responded to Mr Mohamud’s request with foul and abusive language. Mr Mohamud protested at being spoken to in this manner, which led to another barrage of abuse from Mr Khan, who ordered Mr Mohamud to leave.
Mr Mohamud went to his car, but was followed by Mr Khan. Mr Khan opened the passenger door and told him in a threatening manner never to come back. When Mr Mohamud asked him to shut the door, he was punched by Mr Khan. Mr Mohamud got out of the car to close the passenger door. Mr Khan punched him to the ground and severely assaulted him, despite his supervisor telling him to stop.
At trial and appeal it had been held that Morrisons were not vicariously liable for Mr Khan’s actions. Although his job involved some interaction with customers, it involved nothing more than serving and helping them. There was not a sufficiently close connection between what he was employed to do and assaulting a customer.
Mr Mohamud had died before the case went to the Supreme Court, but his family continued with the action and argued that the test of “close connection” was outdated., They sought a new, broader test of “representative capacity”: was Mr Khan acting in the capacity of a representative of the employer at the time of the assault? Alternatively, was Mr Khan was acting within the “field of activities” assigned to him in dealing with Mr Mohamud?
The Supreme Court allowed the appeal, holding Morrisons vicariously liable for Mr Khan’s actions.
They considered the development of vicarious liability. The test for many years was whether the employee’s conduct was “either (a) a wrongful act authorised by the master or (b) a wrongful and unauthorised mode of doing some act authorised by the master.”
However, in Lister v Hesley Hall Ltd  1 AC 215, the court recognised that the second leg of this test was ineffective. It introduced the “close connection” test to remedy this. In Lister, children had been abused by a warden employed by a school boarding house. Lord Steyn had posed the question as to whether the warden’s abuse was so closely connected with his employment that it would be just to hold the employer liable. In that case, the court ruled there was a sufficiently close connection.
The court saw no need to alter the test in the way proposed by Mr Mohamud. The close connection test was sufficient. Mr Khan’s job was to attend to customers and respond to their inquiries. His foul-mouthed response and ordering Mr Mohamud to leave was inexcusable but within the “field of activities” assigned to him. There was no break in the chain by Mr Khan then following Mr Mohamud to his car. In Lord Toulson’s view, “It was a seamless episode.” Further, when he opened the passenger door, he ordered Mr Mohamud to keep away from his employer’s premises, which was reinforced by the assault. It was not something personal between them.
The fact that it was a gross abuse of his position was irrelevant, as was Mr Khan’s true motive. Morrisons had entrusted him to deal with members of the public and it was just that they should be responsible for his abuse of this trust.
On the face of it, this is a surprising decision which arguably broadens the scope of vicarious liability. From a Scottish perspective, the decision is at odds with recent decisions such as Vaickuviene v J Sainsbury plc 2014 SC 147. There, Sainsburys were held not to be vicariously liable when one employee murdered another.
The approach taken here was to consider what was just in the circumstances, and the Supreme Court was at pains to point out that each court will need to make an evaluative judgement in each case. Nonetheless, the danger from an employer’s point of view is that any link to an employee carrying out his “field of activities” will be sufficient to establish that the employer should be held liable.