The claimant in this case was an employee who had had a personal relationship with the MD. She was dismissed after that relationship broke down. The employer argued she was dismissed because of Redundancy and Reorganisation or SOSR. She claimed it was because she'd made a protected disclosure about the firm's tax irregularities. The original tribunal ruled against the claimant, finding, amongst other things, that there had been no protected disclosure because the respondent did not know about them.

The EAT found that the tribunal had made some errors in law. In particular, it was not common ground that the respondent did not know about the allegations regarding tax but that the claimant had not directly told him - it was still a protected disclosure. Also, the tribunal "erred in law in placing the burden proof on the Claimant to show that the reason for her dismissal was that she had made protected disclosures." As Mummery LJ held in Kuzel v Roche Products Ltd [2008] IRLR 799, where an employee positively asserts that there was an inadmissible reason for his dismissal he must produce some evidence supporting a positive course, such as making a protected disclosure, the employee does not have the burden of proving that the dismissal was for that reason.

http://www.bailii.org/uk/cases/UKEAT/2015/0227_12_3006.html