Definition - What does Credible Witness mean?
A credible witness is a witness who is believed to be likely to give an accurate testimony. In order to be deemed a credible witness, the person must have actually seen the event happen, must have paid sufficient attention to it, and must possess knowledge, training, or experience relevant to the event. An apparent, sound moral character also helps to classify one as a credible witness.
Justipedia explains Credible Witness
A testimony from a witness can be very important to a trial. It is necessary to determine whether or not a witness is credible. For example, if an accident occurred on a job site involving the use of heavy machinery, a witness who worked at the site, and who would know if the machinery was being properly used or not, would be more credible than a passerby who was unfamiliar with the machinery. This is because the worker's training would help him understand what actually happened during the accident. This training adds to his credibility as a witness.