Under article 27 of the ILO Constitution, all member States are required to cooperate with a COI, whether directly concerned in the complaint or not. Governments in particular must “place at the disposal of the COI all the information in their possession which bears upon the subject-matter of the complaint”.
As a matter of practice, past COI have invited written submissions and observations from:
- the member State in respect of which the complaint is filed;
- the complainant(s);
- any other interested member State as well as employers’ or workers’ organizations concerned, in particular employers’ and workers’ organizations having consultative status with the ILO;
- members or deputy members of the Governing Body;
- countries neighbouring the member State concerned or having important economic relations with it;
- international organizations within the United Nations system and regional organizations;
- non-governmental organizations operating in the legal, human rights and humanitarian spheres; and
- private companies mentioned in the complaint.
According to the established practice, the COI asks the government of the member State concerned for assurances that no obstacles will prevent the attendance before it of persons whom the COI wishes to hear and that all witnesses would enjoy full protection against any sanction or prejudice on account of their attendance or evidence before the COI.