No, held the EAT in Serco v Dahou.
Mr Dahou claimed the reason for his dismissal was not gross misconduct but union activity. The employment tribunal upheld part of his claim for detrimental treatment and automatically unfair dismissal. Serco appealed and the case was remitted to a fresh employment tribunal.
Serco’s position was that the employment tribunal misapplied the burden of proof by not evaluating its explanation for Mr Dahou’s treatment. The EAT agreed; it did not follow “as a matter of law or logic” that Serco’s purpose was improper just because the employment tribunal was not persuaded that its actions were to address misconduct.
The employment tribunal had taken the burden of proof as in a discrimination case (where prohibited treatment can be inferred unless the respondent demonstrates otherwise) rather than determining Serco’s purpose by reference to evidence and inferences.
This supports the decision in North Essex Partnership NHS Foundation Trust v Bone that detriment requires the employer to have acted (or deliberately failed to act) to deter union participation, this effect being foreseeable is not enough.