A more thorough explanation:

A credible witness is someone who is considered trustworthy and believable when giving testimony in a legal proceeding. This is because they have the necessary experience, knowledge, training, and honesty to provide accurate information.

• A doctor who testifies about a patient's medical condition is considered a credible witness because of their medical training and expertise.
• A police officer who witnessed a crime is considered a credible witness because of their training and experience in law enforcement.
• A victim of a crime who provides testimony is considered a credible witness if they are honest and have firsthand knowledge of the events.

There are several factors that can affect a witness's credibility, including:

• Inconsistent statements
• A reputation for untruthfulness
• Defects in perception
• Prior convictions that show dishonesty or untruthfulness
• Bias

An attorney may try to show that a witness is not credible by pointing out inconsistencies in their statements or a history of lying. On the other hand, an attorney may try to enhance a witness's credibility by showing that they have always been consistent in their statements and have a reputation for honesty.