University of Tasmania
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Lawyers and DNA : understanding and challenging the evidence

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posted on 2023-05-27, 10:17 authored by Cashman, KE
Multi-disciplinary research into the use of forensic evidence in the criminal justice system allows for greater understanding of the processes employed by professionals from the crime scene through to the courtroom. Courts have accepted DNA evidence as robust and reliable forensic evidence for over 30 years. More recently, however, there have been investigations into miscarriages of justice and other criminal cases that demonstrate the risks of assuming that DNA evidence is unproblematic. These cases have identified a failure by lawyers to challenge and understand this type of evidence. Criminal lawyers must ensure that DNA evidence, like all evidence, is explained correctly to the court and given the appropriate weight by the fact-finder. Lawyers have been criticised not only for a lack of understanding of DNA evidence but also for their lack of effective communication with expert witnesses. This thesis explores how lawyers understand and challenge DNA evidence in criminal trials in Victoria and the Australian Capital Territory (ACT). Until this study was conducted, Australian lawyers had not been consulted about the criticisms directed towards the profession in Australian and international forensic reports. Nor had they been asked about their practical experiences in managing DNA evidence in an adversarial criminal justice system. The research for this thesis makes an original contribution to the field of forensic and legal studies in several ways. It shares these practical experiences, uncovers the tensions that exist in using DNA evidence in an adversarial legal system, assesses the greatest areas of difficulty for lawyers and judges in dealing with DNA evidence and evaluates current education initiatives aimed at improving lawyers' knowledge of DNA evidence. This research also reveals how the organisational culture of professionals within an adversarial legal system influences their use of DNA evidence in criminal trials. This thesis analyses these experiences within a legal context. In exploring how lawyers manage and use DNA evidence, this thesis seeks answers to two primary research questions. First, what are lawyers' understandings of DNA evidence and what difficulties do they have in dealing with this type of evidence in criminal trials?; and second, what training opportunities and resources are available to lawyers on DNA evidence and what are lawyers' views about the value of those opportunities and resources? Forty practising criminal lawyers were interviewed for this qualitative study. The lawyers were drawn from several sources ‚ÄövÑvÆ both private and governmental organisations, law firms and the Private Bar in Victoria and the ACT. The perspective of those who observe or interact with criminal lawyers who use DNA evidence in criminal cases was also important. Judges overseeing criminal cases and forensic scientists who present DNA evidence in court also took part in a series of focus groups. These groups are qualified to reflect on how criminal lawyers present and use DNA evidence both pre-trial and in the courtroom. This is the first qualitative study to apply a criminological and legal lens to the practical use of DNA evidence in an adversarial criminal justice system. The results reveal that most lawyers understand the investigative procedures for DNA evidence and the chain of evidence requirements for DNA evidence ‚ÄövÑvÆ those areas where error is most likely to lead to miscarriages of justice. More significantly, the results suggest that a lack of competence is not the only explanation for lawyers' mismanagement or miscommunication of DNA evidence in criminal trials. This thesis argues that cultural and systemic explanations for lawyers' disengagement with DNA evidence and choice to avoid communication with forensic scientists about this evidence should be considered when assessing lawyers' roles in relation to it. The adversarial nature of the Australian criminal justice system influences lawyers' practice and how they learn about DNA evidence. Continuing legal education (CLE) providers do not always provide information that is relevant and accessible to lawyers when they have the greatest need for this information in their daily practice. This thesis makes recommendations for the development of education programs on DNA evidence for lawyers. These and other recommendations recognise and consider how lawyers best learn about complex evidence and the type of learning environment they are most likely to engage with.


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