The standard of care in negligence - can a person's mental illness be taken into account?
Those familiar with negligence will know that in order to establish liability one must show that there has been a breach of a duty, or, a failure by a party to exercise the standard of care required by law which results in damage to the other party, to whom the duty was owed.
On general legal principles, whether a person falls below the standard of care expected is determined objectively by reference to the reasonable person test.
In the recent case of Dunnage v Randall and another  EWCA Civ 673, the Court was asked to consider whether a person's mental state should be taken into account when looking at the standard of care owed by a party. In this case, Mr Randall was suffering from schizophrenia and whilst visiting his nephew (the Claimant), he poured petrol over himself, causing him to die and leaving his nephew, the Claimant with serious burns. The Claimant sought damages from his estate and his household insurers.
At trial, the Judge at first instance held that no one was subject to a duty of reasonable care in respect of acts he could not, or could not reasonably be expected to, control unless the situation included actionable voluntary behaviour. The Judge held that Randall's actions were involuntary due to his extreme mental illness.
On appeal, the Court of Appeal reversed the Judge's finding and held that Mr Randall did owe Dunnage a duty of care not to carelessly injure him despite his supposed lack of capacity and mental illness. The requirements of causation and foreseeability were satisfied and so it was found that Randall had been negligent. The courts have consistently rejected the notion that the standard of care should be adjusted to be subjective and take account of the personal characteristics of the defendant (with the exception of children).
The Court of Appeal held in this case that an individual whose actions (while suffering from an extreme mental illness) had caused injury to the Claimant was liable in negligence. This case therefore reiterates that the standard of care is an objective test and will not be adjusted to take account that lack of capacity or having a mental illness will excuse a person from liability in negligence unless the illness entirely eliminates fault or responsibility.
This case will be of relevance to insurers and employers given the principle of vicarious liability, where employers can be found to be liable for acts of their employees which are committed during the course of their employment.
An employer can also be liable for the acts or omissions of third parties, such as clients or customers, provided that those parties are deemed to be under the control of the employer.
To be in the best position to defeat any such claim, an employer will need to show they have taken all reasonable steps to prevent such acts or omissions from occurring. For example, by having a compliant equal opportunities policy in place and providing training to staff on matters such as equal opportunities/bullying.