Is an employer liable for an employee’s unprovoked violent assault on a customer? Yes, said the Supreme Court in Mohamud v WM Morrison Supermarket plc. Mr Mohamud stopped at a petrol station on 15 March 2008. The petrol station had a Morrisons supermarket attached to it. Mr Khan manned the kiosk. Mr Mohamud went into the shop to see it was possible to print some documents. Mr Khan replied in expletive terms that it was not. When Mr Mohamud objected to being sworn at, Mr Khan ordered Mr Mohamud to leave using foul and abusive language. Mr Mohamud was about to drive off when Mr Khan pursued him and told him never to come back to the petrol station. When Mr Mohamud told Mr Khan to get out of his car, Mr Khan punched him to the head. Mr Khan attacked Mr Mohamud further and ignored the instructions of his supervisor to stop. Mr Mohamud brought a personal injury claim for assault against Morrisions. The issue then arose as to whether Morrisons were liable for Mr Khan’s violent acts.

The Supreme Court held that the acts of Mr Khan were sufficiently connected to his employment for it to be just that Morrisions should be vicariously liable for his acts. It was Mr Khan’s job to attend to customers and respond to their inquiries. When the violent conduct took place Mr Khan was answering Mr Mohamud’s request and was telling him never to come back to his employer’s premises. In giving such an order he was purporting to go about his employer’s business. Whilst it is clearly abuse of his position, the violence which took place was carried out in connection with the business of serving customers. It was therefore just that Morrisons should be responsible for the abuse of position.