A legal expert witness is someone who is called upon to testify in court because he or she has some specific knowledge, experience, or education that may be helpful in a case. For example, if someone is pulled over and charged with driving under the influence of alcohol, but he claims to be taking a prescription medication that can cause blood alcohol levels to appear elevated even while sober, an expert in the pharmacology field may be called to give insight on those claims. In most cases, a legal expert witness testifies willingly and is often compensated for his or her time.
Before someone is allowed to testify as a legal expert witness, his or her status as an expert within a certain field must be firmly established. There is no concrete formula for determining someone’s “expert” status, but choices are generally made by considering a combination of the person’s educational background, work experience, and awards given for work done in a specific field. For instance, if the prosecution is attempting to prove someone was abusive to a child, the court may bring in a child psychologist to determine if certain behaviors exhibited by the child indicate an abusive situation. Although many experts may be qualified to give such a testimony, the prosecution may be more likely to choose someone who specializes in counseling abused children, or who has worked with a large number of children in abusive situations.
Other factors in determining who should act as a party’s legal expert witness include how well he or she handles pressure and expresses opinions and facts. The witness should be able to give detailed information about complex subject matter in a way that allows jury members to comprehend what it is being said. The hiring attorney must also be sure the witness agrees with his standpoint regarding a case to ensure that the witness presents information in a way that will further his case.
In the beginning stages of a trial, the expert will likely review large quantities of information regarding the case and form his or her expert opinion based on that information, as well as any research or tests that may be performed to help back up a particular point of view. Often, the legal expert witness will draw up a report stating his or her opinions on the case or similar situations that may have been previously studied. A deposition may also take place in which the opposing side questions the witness under oath to gain information regarding his or her opinions, knowledge, and research in order to form a rebuttal. Depositions are recorded and/or transcribed by a court reporter.
During the actual trial or hearing, the legal expert witness will be asked to provide his or her credentials as an expert. At that time, the testimony will begin. Experts may be asked to present facts and opinions during the course of testimony. For example, the expert in the child abuse case may be asked what behaviors abused children typically exhibit. This question requires the answer to state facts based on research and statistical analysis. On the other hand, if the question is “Do you think the behaviors the victim is showcasing were caused by abuse?” the answer would be based on professional opinion.