An expert witness is an independent party who - due to their gained knowledge through education, training, and professional experiences – has the right expertise and qualifications within a particular field, such that other individuals may rely on their opinion about the matter. An expert witness is needed whenever “it is necessary to have opinion evidence to assist in the resolution of a dispute”. In practical terms, expert witnesses are part of many court cases. In the UK, expert witnesses are frequently used in civil cases, particularly those involving personal injury, medical negligence, or construction disputes. They are also used in criminal cases - involving forensic evidence or complex financial transactions - where their expertise may be needed to evaluate evidence. Their expert evidence is necessary to help the court understand specific issues, such as the cause of an accident or the technical aspects of a complex commercial dispute.
Expert witnesses are particularly important in cases that involve complex or technical issues, where their specialist knowledge can help to clarify complex concepts and assist the court in making an informed decision. For example, in a personal injury case, an expert witness may be called upon to provide an opinion on the severity of a particular injury and the impact it will have on the victim's life. Moreover, they can also help to ensure that the facts of a case are presented in a clear and concise manner, which can help to avoid confusion or misunderstanding.
Expert witnesses play a crucial role in the legal system of the United Kingdom, as such, the primary duty of an expert witness is to the court (not to the paying party). For this reason, they must provide objective and impartial evidence to assist the court in reaching a decision.
In the UK, the use of expert witnesses is governed by the Civil Procedure Rules and the Criminal Procedure Rules, which set out the procedures and requirements for the appointment of experts and the admissibility of their evidence in court. When appointed in the role of an expert in court proceedings or arbitration, an expert must comply with the rules relevant to the jurisdiction and proceedings, for example, the Civil Procedure Rules (‘CPR’), Part 35 – Experts and Assessors, when a matter is heard in the courts in England and Wales. In addition, expert witnesses can help to improve the efficiency of the legal process by providing evidence that may be admissible in court, which can help to streamline the proceedings and reduce the time and costs associated with a case. Furthermore, the use of expert witnesses is an important aspect of the UK legal system, as they can help to ensure that legal decisions are based on the most accurate and reliable evidence available.
Expert witnesses are important for: