“[…] a list which— (a) contains details of persons who are or have been members of trade unions or persons who are taking part or have taken part in the activities of trade unions, and (b) is compiled with a view to being used by employers, or employment agencies, for the purposes of discrimination in relation to recruitment or in relation to the treatment of workers. (3) “Discrimination” means treating a person less favourably than another on grounds of trade union membership or trade union activities.”
“If there are facts from which the Tribunal could conclude, in the absence of any other explanation, that R [that is, the would‑be employer] contravened Regulation 3 or relied upon information supplied in contravention of that Regulation, the Tribunal must find that such a contravention or reliance on information occurred unless R shows that it did not.”
“An employee who is dismissed shall be regarded for the purposes of this Part [that is, unfair dismissal] as unfairly dismissed if the reason (or, if more than one, the principal reason) for the dismissal relates to a prohibited list and either— (a) the employer contravenes Regulation 3 of the 2010 Regulations in relation to that prohibited list, or (b) the employer— (i) relies on information supplied by a person who contravenes that Regulation in relation to that list, and (ii) knows, or ought reasonably to know, that the information relied on is supplied in contravention of that Regulation.”