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[1947] KB 598.The claimant's husband died during a routine operation after being given a large dose of cocaine instead of novacaine. The accident arose from a series of blunders, which could have been avoided by the implementation of rigorous procedures for dispensing drugs, as well as greater diligence on the part of the various hospital staff members involved. The health authority was held liable in its personal capacity for failing to implement proper procedures; the surgeon was held liable for not exercising proper care. However -- and this is the point that this case is usually cited for -- the authority was not vicariously liable for the acts of the surgeon (see vicarious liability) as it did not exercise 'control' over them. Hilbery J said: "The distinction between a contract for services and a contract of service can be summarised in this way: In one case the master can order or require what is to be done, while in the other case he can not only order or require what is to be done, but how it shall be done."

However, this rather traditional distiction between 'contracts for service' and 'contracts of service' was doubted in cassidy v ministry of health (1951).