Which of the following is essential for a witness to have before providing testimony?

Having firsthand knowledge or experience related to the case is crucial for a witness before providing testimony. This requirement ensures that the witness can speak with authority and credibility about what they directly observed or experienced. Testimonies based on firsthand knowledge are generally more reliable and persuasive in a legal context, as they provide genuine insights into the events in question.

A clear understanding of legal terms and a comprehensive knowledge of criminal law, although beneficial for a witness to have some familiarity, are not prerequisites for giving valid testimony. The legal system primarily seeks factual accounts rather than expert legal interpretations. Similarly, possessing a degree in criminal justice is not necessary for someone to testify, as the value of testimony lies in personal experiences rather than academic qualifications.