A/HRC/19/61 evidence; for this reason, it is advisable to include at least some acting or retired magistrates or prosecutors. At the same time, it is important to reflect a wide range of expertise within the commission to ensure that the work benefits from diverse interpretations of the underlying problems. People of high moral standing from the sciences (especially medical, psychiatric and forensic sciences) and from social science and liberal arts backgrounds, including journalism, should also be included. 62. Where human rights violations have had a distinct ethnic, racial, or religious dimension, it is important to include people who fully understand the plight of affected communities. Under all circumstances careful attention should be paid to the inclusion of women in the composition of the commission. Of additional value is the inclusion of individuals with a gender perspective to better understand the specific ways in which vulnerable persons, including, women, children, lesbian, gay, bisexual and transgender persons, persons with disabilities and persons belonging to a minority or indigenous group suffer from gross violations, including torture and other forms of ill-treatment and how they affect their communities. Geographic and cross-cultural balance in a commission is also of the greatest importance, as long as the standards of expertise and professionalism are not diminished for the sake of political balance. 63. In the case of commissions appointed by the international community, the appointment of members should reflect first and foremost well-recognized expertise in international law. Previous experience with commissions of inquiry has been an important factor in the success of recent commissions. D. Mandate, powers and attributions 64. A commission of inquiry should be created by way of the legal instrument that is most appropriate to its context and should reflect the high importance that States give to such investigative bodies. The legal instrument establishing a commission of inquiry may be an act of parliament, an executive order or decree, or a decision of the highest courts in exercise of their investigatory functions. In all circumstances, the legal instrument establishing a commission of inquiry should identify clearly the terms of reference of the commission’s mandate, including a clear temporal and/or geographic framework that is appropriate for the issue being investigated. The mandate should not excessively broaden the universe of violations to be investigated. The text of the authorizing instrument should also set out clearly the scope of the inquiry, citing with precision the events and issues to be addressed. The terms of reference should be stated in neutral language to avoid the impression of a predetermined outcome. A commission should have flexibility to amend its terms of reference in exceptional circumstances, as long as newly found elements warrant the amendment and the commission’s decision is publicly and transparently explained.43 65. The legal instrument should also clearly establish the powers and attributions of the commission. Regardless of whether the findings of the commission have legal force in the national jurisdiction or are guidelines for future action of State institutions, it is imperative that commissions be seen as “official” bodies whose work and outcome the State pledges to respect and abide by. A commission must have the ability to inspect all documents in public agencies and archives, including those classified as secret or of limited distribution. A commission of inquiry should have subpoena powers; alternatively, it should be empowered to obtain evidence by applying to courts in order to summon witnesses and compel testimony, subject to the right of a person to remain silent if testimony might tend to be self-incriminating. These powers should extend to obtaining warrants for the inspection of places and search and seizure of documents and material evidence. In 43 Istanbul Protocol, para. 107. 17