themselves. When the information was obtained from a third person in circumstances that are secret, it is likely to be extremely difficult or impossible. It is for that reason that UN Special Rapporteur on torture Manfred Nowak and Council of Europe Commissioner for Human Rights Thomas Hammarberg both argue that the burden should be shouldered by the prosecutor to establish convincingly that contested evidence was not obtained through torture.23 A related problem is the use of so-called fruit of the poisoned tree: corroborating evidence collected as a result of investigations prompted by statements obtained under torture. The Convention against Torture is silent on whether the exclusionary rule applies to this kind of evidence. The ban on the use at trial of secondary evidence that was derived from coercive interrogation is, however, a well-established principle in US jurisprudence. The European Court of Human Rights has also suggested that the exclusionary rule with respect to torture is applicable to the fruit of the poisoned tree. In its Jalloh v. Germany judgment, the European Court affirmed that “incriminating evidence—whether in the form of a confession or real evidence—obtained as a result of acts of violence or brutality or other forms of treatment which can be characterised as torture—should never be relied on as proof of the victim’s guilt, irrespective of its probative value.”24 In a June 2010 judgment in the case of Gäfgen v. Germany, the Grand Chamber of the Court elaborated on its interpretation of the scope of the exclusionary rule: [T]he admission of evidence obtained by conduct absolutely prohibited by Article 3 [torture and ill-treatment] might be an incentive for law-enforcement officers to use such methods notwithstanding such absolute prohibition. The repression of, and effective protection of individuals from, the use of investigative methods that breach Article 3 may therefore also require, as a rule, the exclusion from use at trial of real evidence which has been obtained as the result of any violation of Article 3, even though that evidence is more remote from the breach of Article 3 than evidence extracted immediately as a 23 Manfred Nowak, Report of the Special Rapporteur on torture and other cruel, inhuman or degrading treatment or punishment, UN Doc A/61/259, August 14, 2006, http://www.icj.org/IMG/NowakGAReport2006.pdf (accessed September 18, 2009), para. 64; Thomas Hammarberg, Report of the Commissioner for Human Rights Thomas Hammarberg on his visit to Germany, 9-11 and 15-20 October2006, CommDH(2007)14, July 11, 2007, https://wcd.coe.int/ViewDoc.jsp?id=1162763&Site=CommDH&BackColorInternet=FEC65B&BackColorIntranet=FEC65&BackC olorLogged=FFC679 (accessed September 18, 2009), para. 174. 24 European Court of Human Rights [Grand Chamber], Jalloh v. Germany, No. 54810/00, ECHR 2006-, available at www.echr.coe.int, para. 105. 11 Human Rights Watch | June 2010