Yes, held the EAT in Kalu v Brighton & Sussex NHS Trust.
In this case, the employee brought claims of direct race discrimination and of victimisation, in which the protected act complained of was a (settled) previous race discrimination claim against the same employer. In his witness statement the employee had referred to matters which had been settled as part of the previous claim, and on the first day of the hearing he also sought to rely upon bundles of documents which had not been disclosed. The Respondents applied to have the offending evidence excluded. The employment tribunal duly excluded it, remarking that such evidence was not 'material' to the issues that fell to be decided.
The wing members (in a majority judgment) considered that although the employment tribunal had a wide discretion within which it could have excluded the undisclosed documents, it should not have excluded the paragraphs in the employee's witness statement. They commented that "the underlying principle for the Tribunal is the relevance of the evidence before it", and that the employment tribunal should show its reasoning and analysis in exercising its discretion. The excluded paragraphs gave insight into the background of the present claim and, as such, were relevant.
The President of the EAT, Langstaff J, in a dissenting judgment, agreed with the approach of the employment tribunal on the basis that they took into account the relevant factors in determining whether to exclude the evidence.