Rules for an Expert Witness in Civil Court
Proof of Personal Knowledge
- Evidence must be provided as to why the witness is qualified to testify as an expert on the subject at hand. The expert witness may work in a field that provides context and authority over matters in question. For example, if the defendant's sanity is questioned in the court, a psychiatrist may be brought to the stand as an expert witness to testify. Education, work background and previous experience in other court cases may be used as evidence of the expertise of the witness.
The Truth Under Oath
- An expert witness is required to testify under oath that everything she says regarding the facts of the case are the absolute truth. Any act of lying while under oath is considered perjury and may result in criminal charges against the expert witness. Additionally, the expert witness must swear under oath that all the qualifications that make her an expert witness are, in fact, true.
- Expert witnesses must provide written reports that provide full disclosure on a number of issues regarding a court case. An expert witness must provide information on how much he was paid to give his expert opinion. The expert must provide an opinion, in writing, to the questions asked of her, including the basis for all opinions and assumptions. The report must also include all exhibits, including diagrams and pictures, that the expert used to form the basis of his opinion on the case.