Thanks for your patience. To be honest it is difficult to state with any degree of certainty whether this would be a gross misconduct offence or not. There is no list of what amounts to GM and it would depend on the circumstances. It has to be something which is so serious that it breaches the employer/employee relationship and any trust and confidence in it and makes their continued employment impossible.
Often there has to be intent by the employee for actions to be GM, where they intend to do or say something inappropriate or against rules, procedure, etc (e.g. stealing, fighting, swearing).
However, gross negligence can form part of a GM case and if this person’s actions were so grossly negligent#, when considering their level and experience, then it can also amount to GM even if they were not deliberate.
You also have to give the employee the chance to explain himself, why he may have done this error and if there are any mitigating circumstances. In summary, no one can tell you with certainty whether something is GM or not – there will always be a chance that if you decide it is, a tribunal may decide it is not. However, you can cover yourself by conducting a formal and fair disciplinary procedure and showing you had acted reasonably.
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