limitations in accessing historical archives. The sharing and publication of otherwise publicly available information or academic research should not be viewed as unlawful disclosure of state secrets, even when their disclosure into the public domain occurred in violation of secrecy laws. 147. Participating States should adopt legislation to ensure that the general public has access to information held by public bodies. According to the UN Special Rapporteur on the promotion and protection of the right to freedom of opinion and expression, the “adoption of a national normative framework that objectively establishes the right to access information held by public bodies in the broadest possible terms is crucial to give effect, at the national level, to the right to access information. Legislation should be grounded by the principle of maximum disclosure.”206 The grounds for refusing disclosure should be clearly and narrowly defined; non-disclosure of information should be justified on a case-by-case basis, and exceptions should only apply where the risk of substantial harm to the protected interest is greater than the overall public interest in having access to the information. Furthermore, the legislative framework should follow the principle that public authorities generally have an obligation to publish information, a principle which is subject only to reasonable limitations, rather than merely granting access to information upon request.207 Accordingly, public authorities at the national, regional and local levels should be required to regularly publish and proactively disseminate, among other things, data related to their activities, including on their budgets and expenditure, and specific information on human rights matters should also be made easily accessible, not only on demand. In addition, participating States should also take appropriate legislative and other steps to ensure that information held by nonstate actors – such as private companies – that is linked to a public interest is made available to the public or can be accessed as appropriate and is subject only to reasonable limitations. PACE has stated that “business enterprises, including private military and security companies, have the responsibility to disclose information in respect of situations, activities or conduct that may reasonably be expected to have an impact on the enjoyment of human rights”.208 148. Concerning information about gross human rights violations, the UN Special Rapporteur on the promotion and protection of the right to freedom of opinion and expression has emphasized that such information must not be withheld on 206  Report of the Special Rapporteur on the promotion and protection of the right to freedom of opinion and expression, UN Doc. A/68/362, 4 September 2013, para. 98. 207  Ibid. para. 76, which lists core principles and guidelines for the design and implementation of national laws on access to information; and para. 99. See also PACE Resolution 1954 (2013) cited below, which highlights in paragraph 9 a number of key principles that should be taken into account by states in modernizing their legislation and practice concerning access to information. These are based on the “Tshwane Principles” (Global Principles on National Security and the Right to Information), which were adopted by a large assembly of experts from international organizations, civil society, academia and national security practitioners. PACE expressed its support for the principles and called on Council of Europe member states to take them into account when modernizing their legislation and practice in this field. 208  PACE Resolution 1954 (2013), “National security and access to information”, adopted on 2 October 2013, para. 9. Guidelines on the Protection of Human Rights Defenders 73