48 Human Rights in Counter-Terrorism Investigations Most OSCE participating States have some legislation or rules of criminal procedure in force that allow the prosecution to withhold from the defence sensitive information that has arisen in a criminal investigation and would otherwise have to be disclosed. However, the judge must assess how well founded the request for non-disclosure is, by having full access to the evidence and facts of the case, and may sometimes rule that the prejudicial effect of non-disclosure is such that it would prevent a fair hearing. Under international human rights standards, it is prohibited to withhold from the defence information that is exculpatory for the accused.56 In such circumstances, the prosecution faces the dilemma of having to choose between disclosing information – and the consequential endangerment of the source or of the safety of the witness – or discontinuing the legal proceedings, resulting in the dismissal of the case. In cases where the judge allows non-disclosure, the limitation of the right to a fair trial of the suspect needs to be counter-balanced by adequate procedural guarantees in order to ensure an overall fair trial. Case Study – Secret evidence* X, a non-citizen of state A, is suspected of having connections to terrorism. State A legislation provides for the issuance of security certificates to noncitizens suspected of being a threat to the security of the state, leading to their detention and deportation. Both the certificate and detention are subject to judicial review. However, the government can present secret evidence or intelligence to the judge reviewing X’s detention. The domestic legislation prevents the judge from providing access to this evidence and information to the detainee or anyone else if the disclosure would harm national security or the safety of any person. The judge’s decision cannot be appealed. Question: Does the protection of national security justify the non-disclosure of evidence used to issue the certificate and detain X? Does this non-disclosure violate X’s freedom from arbitrary arrest or detention and right to a fair trial? Disclosure of evidence should be as specific and complete as possible. Detained individuals or their lawyers should have been allowed to review the evidence 56 Ibid, para. 33.