News Detail back to listing
A health condition contributing to misconduct is not necessarily a bar to a fair dismissal
- Jul 29, 2025
- Latest News
By Verity Buckingham and Sarah Beeby
An employment tribunal has ruled that an apprentice’s dismissal was fair after he threatened a colleague who he suspected of tampering with his lunch at work. The apprentice unsuccessfully argued that his impulsive reaction was caused by his ADHD and therefore his dismissal was unfair. This decision provides insight into the tribunal’s approach when an employee is dismissed because of conduct arising from a disability.
Background
A garage apprentice, Mr Hayes, sent abusive messages to colleagues and threatened them with personal injury and damage to their possessions after finding his lunch vandalised. Pranks were commonplace at this workplace, but Mr Hayes had already received a final warning in 2021 after his intense reactions to pranks.
The garage suspended the apprentice pending an investigation. Mr Hayes told the investigating manager that he had ADHD. The garage obtained an occupational health report before holding a disciplinary hearing. The occupational health report advised the garage to consider the possibility of Mr Hayes having interpersonal communication deficits as a contributing or mitigating factor in the disciplinary process, but confirmed that the condition did not impair his ability to know right from wrong. The disciplinary manager took into account the fact that Mr Hayes had ADHD, but still considered that the repeated threats amounted to gross misconduct and that his ADHD was not sufficient mitigation to avoid dismissal.
Employment tribunal decision
Mr Hayes argued that his impulsive reaction was caused by his ADHD and brought various claims against the garage, including for unfair dismissal and disability discrimination.
Whilst the tribunal judge was prepared to accept that Mr Hayes’ ADHD had something to do with him sending the abusive messages and making the threats, he found that it was not an inevitable consequence of him having ADHD. The judge also found that the link between Mr Hayes’ ADHD and him sending the messages did not mean he bore no responsibility for his actions. Mr Hayes did not seek to argue otherwise.
The tribunal also considered that the messages were sent over a period of time (10-15 minutes) and there was a large number of messages. This weakened Mr Hayes’ argument that the messages were an impulsive, “heat of the moment” reaction caused by his ADHD.
As a result, the tribunal found it was within the range of reasonable responses for the garage to dismiss Mr Hayes and the dismissal was therefore fair. Mr Hayes’ claims of disability discrimination also failed. The tribunal was satisfied that dismissal was a proportionate means of achieving the legitimate aim of protecting staff from aggressive and threatening behaviour.
Key takeaways
In similar situations, it is sensible to ensure you have medical or occupational health advice on the impact of the health condition on the individual’s behaviour. You should then weigh up any mitigation the health condition might provide, with all the other factors. It is helpful to see from this case that a tribunal will apply a common-sense approach and that the existence of a health condition which may have contributed to misconduct is not necessarily a bar to a fair dismissal in appropriate circumstances.
Authors
About Verity Buckingham
Verity is experienced in all aspects of employment law. She deals mostly with corporate clients advising on contentious and non-contentious employment matters. Verity's contentious practice includes defending claims in the Employment Tribunal and experience of Employment Appeal Tribunal litigation in relation to claims of unfair dismissal, discrimination, equal pay and whistleblowing.
About Sarah Beeby
Sarah is a partner and head of the Firm's tier one ranked People, Reward and Mobility practice in Milton Keynes. A very experienced employment lawyer, she undertakes a full range of employment work for a wide variety of clients in the private and public sectors, including many leading companies and household names. Sarah's work includes advising on large-scale redundancy and restructuring exercises, TUPE transfers and complex outsourcing arrangements, as well as advising on the employment aspects of large corporate transactions, having worked on numerous multi-million pound transactions for an impressive portfolio of