Much academic literature explores the reliability of expert evidence in criminal proceedings in England and Wales. However, almost no attention has been paid to misconduct by experts giving evidence in criminal cases. Whilst rare, its serious impact on the administration of justice and public trust in it means that this area requires analysis. This article explores possible responses to expert witness misconduct occurring in the context of criminal proceedings in England and Wales, noting particularly the differences in responses available, depending firstly upon whether the expert is a registered professional, and secondly whether the expert has stepped outside of their expertise; did not have relevant expertise at all, or was dishonest. Professional disciplinary procedures focus on ‘fitness to practise’, and it is argued that this is sufficient where a registered professional has overstepped their expertise, but has not displayed mala fides. On the contrary, where someone gives evidence purporting to have expertise that they do not, or lies about their conduct as an expert in the case, criminal sanctions are available, appropriate, and should be used. These include contempt of court; perverting the course of justice; fraud by false representation, and perjury.

中文翻译：

---

专家和伪装者：研究英格兰和威尔士刑事审判专家对不当行为的可能反应

许多学术文献探讨了英格兰和威尔士刑事诉讼中专家证据的可靠性。然而，在刑事案件中提供证据的专家的不当行为几乎没有受到关注。虽然很少见，但它对司法和公众信任的严重影响意味着该领域需要分析。本文探讨了对英格兰和威尔士刑事诉讼中发生的专家证人不当行为的可能回应，特别指出了可用回应的差异，首先取决于专家是否是注册专业人士，其次取决于专家是否已经超出了他们的范围。专业知识; 根本没有相关专业知识，或者不诚实。专业纪律程序侧重于“适应实践”，并且有人争辩说，如果注册专业人员超越了他们的专业知识，但没有表现出恶意，这就足够了。相反，如果某人提供声称具有他们不具备的专业知识的证据，或对其作为案件专家的行为撒谎，则应采取适当的刑事制裁措施。这些包括藐视法庭；妨碍司法公正；通过虚假陈述和伪证进行欺诈。