To be a medical expert witness, a person needs to have specialized knowledge about the medical field or health care profession, beyond that of an average person. This expertise is usually gained through education, experience, training, or the accumulation of specialized skills in a specific medical field. For example, a practicing obstetrician would have expertise on delivering babies and a person with a PhD in biology would have expertise in the field. In a court case, a qualified medical expert witness can offer an opinion about a medical issue pertaining to the case.
As a general rule, witnesses in a court case are not allowed to offer opinions about the facts at hand. Instead, they are required to limit their testimony to relevant facts within their immediate realm of knowledge. An exception to this rule is given to a qualified medical expert witness. Since a medical expert witness possesses specialized knowledge about a particular medical field, relevant to the case at hand, she can use her expertise to draw a conclusion about the facts in the case.
Medical expert witnesses frequently testify in civil and criminal cases. In addition, they may be hired to testify at arbitration, mediation, or negotiation proceedings. A medical expert witness can have specialized knowledge about a number of different types of medicine. For example, some witnesses possess expertise relating to audiology or optometry while other medical experts are qualified to testify about bodily injuries, diseases, or infections.
Medical expert witnesses customarily give the fact finder detailed explanations about complex medical questions, which the fact finder would otherwise not understand. For instance, a medical expert witness would not simply testify that the plaintiff has a broken leg. The medical expert witness would testify to the severity of the broken leg, the likely reason for the bone breakage, and the amount of physical therapy required in order for the plaintiff to properly recover from the injury. In short, the expert witness helps the fact finder determine complex issues that are not readily apparent to someone without medical training.
Typically, the credentials of a medical expert witness must be established before the expert can render an opinion. An attorney can do this by asking the witness questions about his or her education, training, skills, and experience within a particular field. Once the proper foundation for expert witness status has been established, a judge will qualify the witness as an expert. Most expert witnesses are paid to testify on behalf of one of the parties.