23 witness’s trial testimony is not necessarily unreliable simply because the witness was subject to improper pressures in making an earlier, out-of-court statement’.92 In at least one case, in-court testimony has been considered tainted by continued coercion and therefore inadmissible and a violation of due process.93 However, courts may also find that sufficient time has elapsed between the torture and the trial testimony that the trial testimony is not tainted by the prior torture.94 The reliability approach to third party ‘torture evidence’ was also used in the case of Mohammed v Obama95 before the US District Court in the District of Columbia, which discussed the approach in some detail. The evidence in question was a statement inculpating Mohammed made by another Guantanamo Bay detainee (Binyam Mohammed) during an interrogation in Guantanamo. The statement by Binyam Mohammed followed his severe torture in secret detention centres prior to the detainee’s extraordinary rendition, all at the behest of the United States. Binyam Mohammed’s statement in Guantanamo was relied on by the state to justify Mohammed’s detention there. Although this was a habeas corpus96 petition rather than a criminal trial, the Court drew upon the ‘existing case law in the criminal area as a useful, albeit not perfect, analogy’.97 It concluded: II.5 ‘The earlier abuse had […] ‘dominated the mind’ of Binyam Mohamed to such a degree that his later statements to interrogators are unreliable. […] In reaching this conclusion, the Court does not doubt the abilities or experience of Special Agent [Redacted], nor his account of his humane treatment of the witness [in Guantanamo Bay]. Rather, based on the factors discussed above, the Court finds that Binyam Mohamed’s will was overborne by his lengthy prior torture, and therefore his confessions to Special Agent [Redacted] do not represent reliable evidence to detain Petitioner’.98 The ‘reliability’ approach is not necessarily used across all jurisdictions in the United States. One federal court, for example, has concluded that considerations similar to those applicable to coerced confessions should also apply to coerced third party statements: ‘[A]lthough there is no absolute parallel between the exclusionary rule relative to confessions and that relative to impeaching statements of witnesses, there is a point at which the same considerations apply to both. That point has been reached here because there is a substantial claim by the defendant that the impeaching statement offered by the government was obtained by police threats and other blatant forms of physical and mental duress. Where such a claim is made, and supported by sworn testimony, the court has a duty to conduct its own inquiry and to exclude the statement if found to have been unconstitutionally coerced’.99 Excluding derivative evidence: the fruits of the poisonous tree At times, confessions or statements procured through torture will lead investigators to other pieces of evidence – such as a body, a weapon or a crime scene. Arguably, the investigators would not have happened upon this evidence but for the torture. Should the evidence therefore be excluded in addition to the statement? The fruits of the poisonous tree doctrine prohibits reliance on evidence derived from illegal activity, also known as ‘derivative evidence’. According to this principle, if the prosecution were able to rely on this derivative evidence, it would defeat some of the key objectives of the prohibition on ‘torture evidence’. For example, there would continue to be an incentive for police to torture suspects or, indeed, other individuals as it could continue, albeit indirectly, to generate evidence which could then be used to convict a suspect. As the US Supreme Court explained in Nardone v United States: ‘To forbid the direct use of methods thus characterized, but to put no curb on their full indirect use, would only invite the very methods deemed ‘inconsistent with ethical standards and destructive of personal liberty’.100 II.5.1 International standards The position in international law on derivative evidence is not altogether clear. Article 15 of the UN Convention Against Torture does not tackle the issue. Respect for the right to a fair trial and the prohibition against torture arguably would require the exclusion, not only of statements elicited by torture,