Tainted by torture: Examining the use of evidence obtained by torture


In many parts of the world, torture is used by the police and others as a short-cut in criminal investigations, as a means of exerting control over detainees, to gather ‘intelligence’, to solicit leads and to obtain confessions.

International law prohibits reliance on ‘torture evidence’ because: (a) statements made as a result of torture are involuntary, inherently unreliable and violate the right to a fair trial; (b) to rely on such evidence undermines the rights of the torture victim; (c) it indirectly legitimises torture and in so doing taints the justice system; and (d) prohibiting reliance on the fruits of torture acts as a form of deterrence and prevention. The exclusionary rule plays a key role in the legal architecture underpinning the prohibition on torture. But reliance on ‘torture evidence’ in criminal cases continues to be routine in many places.

Despite the requirement under international law to exclude torture evidence, some countries simply fail to do so. More commonly, countries have an exclusionary rule, but one which is incomplete:

i) Some countries rely on general rules for the exclusion of illegally obtained evidence, which requires some form of judicial discretion or balancing act in deciding whether to admit the evidence

ii) A number of countries only prohibit reliance on statements obtained from the torture of the defendant and not evidence obtained from the torture of a third party.

iii) Many legal systems focus on the prohibition on ‘confessions’ or ‘statements’, without any reference to physical or derivative evidence which has resulted from torture. International law is also unclear on derivative evidence or ‘fruits of the poisoned tree’.

Many criminal justice systems rely on confessions as the main evidence on which convictions are founded. This exacerbates the risk of coercion, including torture. In response, some countries apply special protections, including a requirement for corroborating evidence and/or the need to demonstrate that procedural safeguards have been complied with. The need to move away from coercive policing practices and confession-based justice is gaining traction at an international level as a key protection against torture. A universal set of standards for non-coercive interviewing methods and procedural safeguards has, for example, been recommended.

Even where a country has a clear exclusionary rule in law, this does not always succeed in precluding reliance on ‘torture evidence’ in practice. It is crucial to have a fair and effective legal procedure for identifying and excluding ‘torture evidence’. Many countries fall short here, for example, because they place an unreasonable burden on the defendant to prove that torture occurred or because they rely too heavily on types of evidence which are not practical to obtain. Many other factors affect whether exclusionary rules work, including whether there are trained professionals applying the rules; broader institutional incentives and cultures at play in the justice system; and practical barriers, such as failures to protect torture victims in detention.

In practice, where torture is identified in the course of proceedings to exclude evidence, there is rarely an obligation on competent officials to initiate a criminal action. In general, criminal investigations require a formal complaint to be made by the victim. The exclusionary rule is also just one of a wide range of remedies and reparations for victims mandated by international law.

Our report includes recommendations to make the international prohibition on reliance of ‘torture evidence’ more effective.