Under general common law principles of civil liability, employers are generally liable for the actions of employees carried out in the course of their employment - a difficult phrase which has given rise to much case law. But equally, someone who employs an independent contractor to carry out works is not held liable for their negligence on the grounds that he has no control over their actions.
The courts have developed a number of exceptions to this rule. One is where the employer has specifically authorised the commission of the act causing damage. Second, the employer may be independently liable if he was negligent in the choice of the contractor who caused the damage. And third, in some situations the type of work involved gives rise to a non-delegable duty, making the contractor's employer liable for his actions.
Two main types of non-delegable duty have been developed by the courts. The first arises where the work can be said to involve extra-hazardous activities - an open-ended concept, but one that includes, for example, the use of combustible material. The second concerns situations where dangers are created on a public highway.
Rowe v Herman and others (Court of Appeal, Civil Division, 9 June 1997) concerned occupiers who had hired a contractor to build a garage on their land. It was accepted that the work did not involve extra-hazardous activity. But the contractor placed metal plates across a public pavement to protect it from the passage of heavy lorries - these were left when the he vacated the site, and a pedestrian walking at night tripped over them and fractured his ankle.
The contractor could be liable for negligence in such a situation, and the pedestrian had also sued the highways authority responsible for the condition of the pavement. But the question at issue in the present case was whether the occupiers were also liable. The trial judge had accepted that it was the entirely the contractor's idea to put down the metal plates, but held that once he had left the occupiers were under a duty to ensure that no hazards were left on the highway.
The Court of Appeal felt it necessary to explore the true nature of the non-delegable duty involving highways by examining the case law on the subject. The court considered that this all involved obstructions to the highway being caused as a result of works carried out under statutory powers and where the employer was required to carry them out.
The present case was quite different. There was no duty to construct the garage, and the obstruction caused by the metal plates was not a necessary part of those works.
The Court felt that had the accident occurred while the contractor was still at work, the occupiers would not have been liable. It did not seem logical that a duty could suddenly arise once the contractor had left the site. The reasoning underlying the general rule concerning non-liability for the actions of independent contractors was that the employer normally had no direct control over the way such a contractor carried out the work. Similarly, it should follow that he had no control over the way a contractor cleared up following completion of the works. The employer was therefore under no duty of care, and the claim was struck out.