Occupational Stress in UK Law

Here again, it is important to distinguish between signs of stress and signs of impending harm to health. Stress is merely the mechanism which may but usually does not lead to damage to health. If the employee or his doctor makes it plain that unless something is done to help there is a clear risk of a breakdown in mental or physical health, then the employer will have to think what can be done about it.

Harm to health may sometimes be foreseeable without such an express warning.

Unless he knows of some particular problem or vulnerability, an employer is usually entitled to assume that his employee is up to the normal pressures of the job. It is only if there is something specific about the job or the employee or the combination of the two that he has to think harder. Generally he is entitled to take what he is told by or on behalf of the employee at face value.

But how strong should those indications be before the employer has a duty to act? Mr Hogarth argued that only 'clear and unequivocal' signs of an impending breakdown should suffice. But in view of the many difficulties of knowing when and why a particular person will go over the edge from pressure to stress and from stress to injury to health, the indications must be plain enough for any reasonable employer to realise that he should do something about it.

Having shown a breach of duty, it is still necessary to show that the particular breach of duty found caused the harm. It is not enough to show that occupational stress caused the harm. However, the employee does not have to show that the breach of duty was the whole cause of his ill-health: it is enough to show that it made a material contribution: see Bonnington Castings v Wardlaw [1956] AC 613.

This is, I think, useful practical guidance, but it must be read as that, and not as having anything like statutory force. Every case will depend on its own facts and the well-known statement of Swanwick J in Stokes v Guest, Keen and Nettlefold (Bolts and Nuts) Ltd [1968] 1 WLR 1776, 1783, remains the best statement of general principle:

It is foreseeable injury flowing from the employer's breach of duty that gives rise to the liability. It does not follow that because a claimant suffers stress at work and that the employer is in some way in breach of duty in allowing that to occur that the claimant is able to establish a claim in negligence. As Simon Brown LJ put it in Garrett v Camden London Borough Council [2001] EWCA Civ 395, paragraph 63: