Balfour Beatty Engineering Services Ltd v Unite the Union [2012] EWHC 267

When calling upon employees to take strike action against their employers, trade unions must, under the relevant legislation, ensure that "so far as is reasonably practicable, every person who is entitled to vote in the ballot must:

(a) have a voting paper sent to him by post at his home address or any other address which he has requested the trade union in writing to treat as his postal address; and

(b) be given a convenient opportunity to vote by post."

Mistakes may be made that do not invalidate a strike ballot and, by extension, any strike action. However, employers and others may challenge the validity of ballots and seek injunctive relief to stop strike action on a number of grounds,