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Workplace stress and harassment claims span multiple legal frameworks: personal injury litigation (breach of duty by the employer), employment tribunal claims (discrimination or disability under the Equality Act 2010), and health and safety enforcement. In all of these, psychiatric evidence plays a central role, establishing the reality of the claimant’s mental health condition, linking it to workplace factors, and assessing prognosis and ongoing impact.
Personal injury claims: negligence and employer’s duty of care
When an employee develops depression, anxiety or another psychiatric condition due to workplace stress, they may bring a personal injury claim for damages. The claim alleges that the employer breached a duty of care towards the employee.
The employer’s duty of care in occupational health is now well-established in English law. Employers must take reasonable care to protect the physical and psychiatric health of their employees. This includes:
- Foreseeable harm: The employer must have been aware, or ought reasonably to have been aware, that the work imposed a risk of psychiatric harm (through excessive workload, harassment, lack of support, or other known stressors).
- Breach of duty: The employer failed to take reasonable steps to mitigate the risk (by adjusting workload, providing support, or addressing harassment).
- Causation: The breach caused psychiatric injury to the employee.
- Quantifiable loss: The employee has suffered measurable harm (medical treatment costs, lost earnings, diminished quality of life).
Foreseeability is critical. An employer cannot be liable for unforeseeable consequences. However, after high-profile cases (e.g. Barclays Bank v Kapur, cases involving bullying in public services), courts have recognised that psychiatric harm from excessive workload, bullying or harassment is reasonably foreseeable, especially if:
- The employee had communicated concerns to management.
- The stressor is ongoing or cumulative (workload increased over months or years).
- Other employees had previously suffered similar harm in similar roles.
- The employer was aware of mental health policies or guidance (NHS stress standards, ACAS guidance) but failed to implement them.
The psychiatrist’s expert evidence addresses whether the claimant’s psychiatric condition is genuine, arises from workplace stressors (rather than pre-existing illness or other causes), and what prognosis and future treatment are needed. This evidence is essential to damages quantification.
Employment tribunal claims: disability discrimination and harassment
Employment tribunals are a separate jurisdiction. A claimant can bring claims for:
Disability discrimination under the Equality Act 2010: If the employee has a disability (as defined in the Act) and the employer discriminates against them, the tribunal can award compensation. For psychiatric conditions, this typically means the employee must show that their condition is a “disability” under section 6 of the Equality Act 2010.
Section 6 defines disability as: a physical or mental impairment that has a substantial and long-term adverse effect on the person’s ability to carry out normal day-to-day activities. “Substantial” means more than minor or trivial. “Long-term” means the impairment is likely to last at least 12 months.
A psychiatrist’s evidence is essential to establish whether the claimant’s condition meets this statutory definition. For example:
- Diagnosis: What is the psychiatric condition (depression, anxiety, PTSD)?
- Severity: Is the impairment substantial? Does it significantly limit the person’s ability to carry out everyday activities (concentration at work, social interaction, self-care)?
- Duration: Is it likely to last at least 12 months?
- Functional impact: How does it affect work performance, relationships and daily functioning?
Harassment claims: The Equality Act 2010 also prohibits harassment related to a protected characteristic. If an employee is harassed due to a disability (psychiatric condition), or because of disability-related factors (e.g. harassment about mental health), this is actionable. The claimant must show the harassment created a hostile or degrading environment.
Psychiatric evidence supports these claims by documenting the psychological impact of harassment and the causal link between the harassment and psychiatric symptoms.
What the psychiatric expert assesses
In work stress cases (whether personal injury or employment tribunal), the expert’s assessment covers:
Occupational history and stressors: The expert takes a detailed account of the claimant’s job, responsibilities, workload, management relationship, and specific stressful events or patterns (bullying, excessive deadlines, unsupportive environment, changes to role without notice).
The expert explores whether these stressors are objective and documented (workload measured by hours worked, harassment evidenced by emails or witness accounts) or subjective perceptions (the claimant felt undervalued, though there is no external evidence).
Psychiatric diagnosis and symptomatology: As in any psychiatric assessment, the expert diagnoses the condition (depression, generalised anxiety disorder, PTSD from workplace trauma, adjustment disorder) and rates severity using standardised measures.
Occupational causation: The expert addresses a key question: Did the workplace stress cause the psychiatric condition? This requires:
- Timeline: Did symptoms begin or worsen coinciding with workplace stressors? A claimant with longstanding depression who experiences work stress but whose depression predates the stress will have a weaker claim.
- Specificity: Do the symptoms relate to the workplace? For example, PTSD-like flashbacks of a confrontation with a manager, or anxiety triggered by emails from a bullying colleague, suggests a specific link. Generalised depression unrelated to work-specific triggers is harder to attribute solely to occupational factors.
- Pre-existing conditions: Did the claimant have prior mental health problems? Pre-existing vulnerability does not eliminate occupational causation—a person with a genetic predisposition to depression can still suffer work-triggered depression—but it is relevant context.
Reversibility and prognosis: Has the claimant left the workplace, and if so, has their psychiatric condition improved? Recovery after leaving the stressful environment supports the link between the workplace and the condition.
The expert assesses the likelihood of ongoing symptoms. If the claimant has recovered or significantly improved, damages for future psychiatric treatment are reduced.
Functional impact at work and beyond: How has the psychiatric condition affected the claimant’s capacity to work? Has the claimant taken sick leave, been dismissed, or been demoted? How has it affected relationships, self-care, sleep? This evidence is used to calculate damages (loss of earnings, cost of treatment, diminished quality of life).
Workplace stress assessment
Expert psychiatric assessment in stress cases includes: recognition of stress risk factors (high workload, lack of control, role ambiguity, poor support); timeline of stress exposure and symptom onset; whether the stressor was foreseeable to the employer; whether the employer took steps to mitigate (occupational health support, adjustment); and functional impairment resulting.
Employer duty of care in stress cases
The employer’s duty of care requires reasonable steps to protect psychiatric health. Breach occurs when: workload is excessive without support; employees have no control over work decisions; management is unsupportive; bullying or harassment is not addressed; or changes are implemented without communication. When such breaches occur, psychiatric evidence will address the causal link between specific workplace failures and the claimant’s symptoms.
Distinguishing psychiatric injury from performance issues
A common defence is that the claimant’s role was objectively demanding, or that they performed poorly, and their psychiatric symptoms are a response to poor work performance or disciplinary processes, not a cause. The psychiatrist must address this:
- Did symptoms precede the disciplinary process, or follow it?
- Are symptoms specific to workplace triggers, or generalised?
- Was the claimant’s performance genuinely poor, or affected by emerging psychiatric symptoms (concentration problems, absence from illness)?
A careful timeline of events, including sick leave dates and communications, helps the expert disentangle cause from effect.
Key points
- Workplace stress claims combine personal injury (breach of duty) and employment tribunal (disability discrimination, harassment).
- Employers have a duty of care to protect employees from foreseeable psychiatric harm; foreseeability is high where bullying or excessive workload is known.
- The Equality Act 2010 defines disability as substantial, long-term impairment affecting normal day-to-day activities; psychiatric conditions can meet this threshold.
- Psychiatric evidence addresses diagnosis, severity, causation (link to workplace stressors), reversibility and functional impact.
- ACAS guidance and HSE stress management standards provide benchmarks for acceptable workplace practice; employer failure to follow these strengthens the claimant’s case.
- Timeline and specificity of symptoms (do they coincide with workplace stressors?) are key to establishing occupational causation.
Related: Find a medico-legal expert