§ Lord Lester of Herne Hillasked Her Majesty's Government:
Whether their proposal to entrench subsidiarity further into the Treaty of European Union, referred to in A Partnership of Nations, would mean that the European Court of Justice will decide upon the interpretation and application of the principle of subsidiarity; and, if not, which European institution would decide whether the principle of subsidiarity had been breached.
§ Baroness Chalker of WallaseyThe principle of subsidiarity is written into the European Community Treaty in Article 3b. The European Court of Justice is the final arbiter for the EC Treaty, and subsidiarity is therefore justiciable. The UK proposal to entrench subsidiarty further into the treaty is intended both to clarify the application of the principle by all institutions, and to guide future interpretation of the principle by the ECJ.