What are the Most Important Duties of the Expert Witness

Legally, the duties of an expert witness vary from country to country—however, the informal requirements are shared among experts throughout the world. In England, the relevant laws governing expert witness testimony are part of the 1998 Civil Procedure Rules. These were later supplemented by similar Criminal Procedure Rules. They require an expert witness to be an independent analyst, who possesses a minimum level of qualifications in their field of expertise.

The witness prepares an expert report that will be used as evidence in the trial. They may also be required to analyze the arguments of both sides and provide a separate analysis on their points of agreement and disagreement with each. Experts may also be hired as consultants by a party who is preparing for a legal battle, though in this case the laws governing them are less stringent. They can act as advisers effectively “shadowing” litigation or a trial. Like witnesses in ordinary legal cases, perjury is a serious offense with regards to the testimony of expert witnesses.

One of the most common classes of expert witness in the modern age is the forensic scientist. All forensic scientists specialize in applying their branch of science—biology, chemistry, or engineering, for example—to court cases. They prepare reports with their analysis of the situation. In a murder case for instance, a forensic scientist is charged with determining the cause of death and examining elements of the scene of the crime for signs of the killer.

“Forensic” can apply to other branches of knowledge with applications to law, such as forensic accounting. Forensic accountants analyze ledgers, bank reports, and other pieces of financial evidence which may be involved in fraudulent business practices or other white-collar crimes. Forensic engineers analyze structures and determine the most likely source of failure, used to determine fault in a civil case if a particular architectural structure fails.