ECtHR held that the right to collective bargaining came within article 11 ECHR, so that a ban on civil service trade unions was unlawful. This was at the heart of art. 11, so that any restrictions had to pursue a legitimate aim proportionately.
ECtHR: “art.11 of the Convention safeguards freedom to protect the occupational interests of trade-union members by the union's collective action, the conduct and development of which the contracting states must both permit and make possible.” Unions must be able to strive for their members’ interests, regardless of what form they use for this. “Two guiding principles for art 11: first, the Court takes into consideration the totality of the measures taken by the state concerned in order to secure trade-union freedom, subject to its margin of appreciation; secondly, the Court does not accept restrictions that affect the essential elements of trade-union freedom, without which that freedom would become devoid of substance.” A non exhaustive list (more can be added in the future) of these essential elements are the right to form and join a trade union, the prohibition of closed-shop agreements and the right for a trade union to seek to persuade the employer to hear what it has to say on behalf of its members.