Credibility is important in litigation, practically and from a substantive legal perspective. Practically, if you don’t come across as likeable or believable, then you’re likely going to have a difficult time convincing a judge or jury that what you’re saying is true. Legally, appellate courts are very deferential to trial court or jury determinations of credibility. In other words, an appellate court will very rarely (if ever) overturn a lower court’s credibility determination.
For this reason, the credibility of witnesses is always a relevant issue in a lawsuit. Mitchell v. Kardesch, 313 S.W.3d 557, 675 (Mo. 2010). Anything that has the tendency of throwing light on the accuracy, truthfulness, and sincerity of a witness is proper for determining the credibility of the witness. Newell Rubbermaid, Inc. v. Efficient Solutions, Inc., 252 S.W.3d 164, 171-72 (Mo. Ct. App. 2007). A jury is entitled to know information that might affect the credibility of the witness, and the weight to be given to his or her testimony.
Before appearing at a hearing or trial, it is very important then that an adequate amount of preparation be done to prepare for the tone and substance of the testimony.