Caswell v Powell Duffryn Associated Collieries Ltd [1940] AC 152
Employer’s liability for injury and death of an employee due to breach of a statutory duty and the role of contributory negligence.
Facts
A mine worker was responsible for periodically cleaning the movable plates of a coal-transporting conveyor belt, instructed to ensure that the machine was off beforehand. The lever to turn it off was operated by a man at a far distance from the machine and there was no signalling system. One day, the man was found dead, caught in the machine’s belts.
Issues
The question arose as to whether the employer was liable for the employee’s death due to a breach of statutory duties concerning dangerous machinery under Section 55, Coal Mines Act 1911. The two defences raised concerned (1) whether there were reasonably practicable exceptions to the employer’s duty; and (2) whether the employee’s negligence was a contributory cause of death.
Decision/Outcome
Firstly, the Court held that the employer was under a statutory duty to ensure that the dangerous machine was fenced and to guarantee a reasonably safe system for the performance of the employer’s duties. The employer failed to fulfil these duties and did not prove that it was not reasonably practicable to take steps to prevent these breaches, and was thus liable. Secondly, as to the question of contributory negligence, the Court held that the employer will not be liable for a statutory breach if the injury was “caused wholly or in part by the omission of the workman.” (p 169) The Court held that the care expected of an employee must be assessed in lieu of surrounding circumstances and that, on the facts, there was no sufficient evidence to show that the employee was guilty of any fault or acted negligently. Accordingly, the Court held the employer’s liability for the employee’s death.
Word Count: 298 words
Updated 19 March 2026
This case summary accurately reflects the decision in Caswell v Powell Duffryn Associated Collieries Ltd [1940] AC 152. The core legal principles described — employer liability for breach of statutory duty regarding dangerous machinery, the burden on the employer to show reasonable practicability, and the treatment of contributory negligence — remain historically accurate as a statement of the law as it stood at the time of the decision.
Readers should be aware of two important legal developments. First, the Coal Mines Act 1911 has been repealed and replaced by successive legislation, most recently consolidated and updated through the Mines Act 1954 and subsequent health and safety legislation. The principal framework now governing mine safety and employer duties in the workplace is the Health and Safety at Work etc. Act 1974 and associated regulations, including the Mines Regulations 2014. The specific statutory provisions discussed in the case therefore no longer apply in their original form.
Second, and more significantly, the defence of contributory negligence as discussed in this case must now be read in light of the Law Reform (Contributory Negligence) Act 1945, which came into force after this decision. Under the 1945 Act, contributory negligence no longer operates as a complete defence but instead allows damages to be apportioned. The all-or-nothing approach to contributory negligence reflected in the House of Lords’ reasoning in this case was effectively superseded by that statutory reform. The case therefore retains academic and historical value — particularly regarding the interpretation of statutory duties and reasonable practicability — but should not be relied upon as a current statement of the law on contributory negligence.
