On 20 March 2023 the ECtHR published a new version of the Rules of Court on its website. They clarify third-party intervention in amendments to Rule 44 (2) and (3) (b). These rules govern the conditions and time limits for the submission of written comments or participation in hearings by the Commissioner for Human Rights, by contracting parties not party to the proceedings, and by persons other than the applicant. The amendments were adopted by the Plenary of the Court on 3 March 2023 and entered into force on the same day.

On the basis of Rule 32 and in parallel, the President of the ECtHR issued a Practice Direction on how third parties may intervene, the procedures and requirements to be followed, and the role such intervention plays in the work of the Court. The guidelines are linked to Art. 36 (2) ECHR, which concerns third-party intervention other than that of the Contracting Party to the proceedings or the applicant in applications before the ECtHR. In addition, Art. 3, second sentence of Protocol No. 16 allows any other High Contracting Party or person to take part in advisory-opinion proceedings.

The Practice Direction provides comprehensive guidance on the following:

• The role of third-party intervention in the Court’s procedure;
• What third-party intervention involves;
• The stages in the proceedings before the Court when third-party intervention is possible, and the time limits for seeking leave to intervene in each possible scenario;
• Who may intervene as a third party under these provisions;
• When a third party is invited or permitted to intervene;
• The representation of third parties;
• The language, content, and manner of requesting leave to intervene;
• The requirements to be met by the written comments and oral submissions of the interveners.