Expert evidence The UN Safeguards stipulate that capital punishment can only be imposed when the guilt of the person is based on “clear and convincing evidence leaving no room for alternative explanation of facts.” ICCPR article 14 underlines the parties’ right to examine hostile witnesses as a significant element of a fair trial. The UN Special Rapporteur on Extrajudicial, Summary, or Arbitrary Executions demands that, “Defendants must be presumed innocent until their guilt has been proven without leaving any room for reasonable doubt, in application of the highest standards for the gathering and assessment of evidence. All mitigating factors must be taken into account”.20 Practice in the use of expert witnesses to assist the court in the determination of guilt varies across Asia and in many countries the defence have no right to call their own experts. In India, defence lawyers may seek the assessment or advice of experts with certain evidence, but this is rarely done at the trial stage of a death penalty case. None of the 20 death penalty lawyers interviewed by Project 39A engaged with evidence in any of their cases. In the 20 cases examined for this study, DNA evidence was used to convict the accused in seven cases and in one of these cases it was the sole piece of evidence on which the conviction was based. Defence lawyers in these cases did not challenge this evidence. The lawyers revealed that they believed that DNA evidence is unimpeachable evidence. In only one case, the defence lawyer suspected that his client probably had mental health issues. However, no mental health diagnosis was conducted and nor was this argument presented before the court. In India, out of the 20 cases examined, in only one case, the defence lawyer suspected that his client probably had mental health issues. However, no mental health diagnosis was conducted and nor was this argument presented before the court. In Taiwan, lawyers interviewed by TAEDP felt that substantive and effective defence in death penalty cases requires expertise in psychiatry, psychology and social work. However, lawyers often lack expertise beyond the legal field and may not have access to assistance of experts from other professions. According to the current Taiwanese Code of Criminal Procedure, defence lawyers are not allowed to select expert witnesses at their own discretion. Instead, they must request the prosecutor or the court to select experts or authorities to carry out the evaluation, and the prosecutor or the court will decide whether or not to do so. 20 Extrajudicial, summary or arbitrary executions: Report by the Special Rapporteur. UN document: E/CN.4/1997/60, 24 December 1996, para.81. https://documents-ddsny.un.org/doc/UNDOC/GEN/G97/100/51/PDF/G9710051.pdf?OpenElement 15