The EAT in Abbey National PLC v Fairbrother (relating to an employee raising a grievance when, amongst other things, colleagues referred to her as Frau Fairbrother and made Nazi salutes to her after she gave detailed instructions to colleagues about how to perform some work) have held that when considering an Unfair (Constructive) Dismissal claim following a resignation due to an employer failing to uphold an employee’s grievance, Tribunals should apply a range of reasonable responses test to the employers treatment of the grievance.

An employer is under a duty to act reasonably. They must not act irrationally or perversely and must not take account of irrelevant material and must not fail to take account of relevant material. They must not take decisions that no reasonable employer would take. 

This decision gives employers a wide band of discretion when dealing with grievances as irrationality and perversity requires far more than an employer simply preferring one account of events to another, which is what a large number of grievances boil down to. As long as employers follow a reasonable procedure and come to a reasonable and justifiable conclusion on the available evidence gathered in the course of the grievance, there is unlikely to be a significant risk of a successful Unfair (Constructive) Dismissal claim based on giving a grievance outcome with which the employee disagrees.