A milkman was expressly forbidden by his employer to give lifts to passengers. He nevertheless allowed a boy to help him deliver milk, and the boy was injured by his negligent driving. In Rose v Plenty, why was the employer vicariously liable?

Correct answer: B) The employee was doing an authorised act (delivering milk) in an unauthorised manner, for the purposes of the employer's business

Explanation

An employer is vicariously liable for torts committed by an employee in the course of employment. A prohibited act may still be within the course of employment if it is done in furtherance of the employer's business, as in Rose v Plenty where the boy was helping with deliveries. By contrast, in Hilton v Thomas Burton employees on a 'frolic of their own' were outside the course of employment.