Tribunal cannot take additional material into account when deciding whether dismissal was fair

In its decision, the EAT said that the reason for the employee's dismissal was "the reason which was extant and operative in the mind of the employer". This meant that the original employment tribunal erred when it referred to previous warnings held on an employee's file as evidence that dismissal was "within the range of reasonable responses" by the employer. The EAT said, that the tribunal should have confined itself to the single, specific incident relied on by the employer.

The employee, a Mr Nejjary, had been dismissed from his hospitality management role with Aramark Ltd. He had previously been suspended from the company on full pay, however Aramark expressly ignored the warnings he had received for these previous incidents when making its decision.

In each case, the alleged misconduct was a "failure to follow appropriate procedures" for checking that events would run properly. The incident leading to Nejjary's ultimate dismissal involved his failure to check a booking sheet before a breakfast meeting at Goldman Sachs, leading to problems with the meeting.

Employment law expert Michael Ryley of Pinsent Masons, the law firm behind Out-Law.com, said that the decision was a reminder that the test to determine whether a dismissal was unfair relates to "the state of mind of the employer at the time".

"Of course, if there was good reason to justify dismissal but the employer was not aware of it at the time, this can cast a very different light with hindsight," he added. "In those circumstances, knowledge acquired after the event can be used to defend a claim for breach of contract and may go to the question of what compensation - if any – is just and equitable to award for the unfair dismissal."

Under the Employment Rights Act (ERA), an employer must be able to show that the dismissal was for a potentially fair reason such as conduct, capability, redundancy or breach of some statutory restriction. In addition, the employer must act reasonably in treating that reason as a sufficient reason for dismissal. However, a tribunal has the power to reduce the amount of compensation awarded to the employee where a dismissal was unfair but was "to any extent caused or contributed to by any action of the complainant".

The employment tribunal found against Nejjary during his original unfair dismissal claim; stating that although dismissal would "normally be outside the range of reasonable responses" by an employer for a one-off incident of the nature relied upon by Aramark, in this case Nejjary had received "previous written and verbal warnings for capability arising out of similar circumstances". Even if the dismissal had been unfair, it added, Nejjary's conduct "inexorably led" to it to the extent that it would not be just and equitable to award compensation.

However, the EAT disagreed. The employment tribunal had, it said, erroneously "built back into the equation" issues that the employer did not have in its mind when it decided to dismiss Nejjary. The tribunal should have confined itself to the specific reason for dismissal and considered whether that alone was sufficient, it added.

In addition, it could be inferred from the original tribunal's decision that when it had assessed Nejjary's "contributory fault" with regards to his dismissal the tribunal had once again considered his conduct in respect of other matters, the EAT said. When assessing contributory fault under the ERA, it said, a tribunal could only consider matters "causally connected to or related to" the dismissal.