Which type of evidence is based on personal knowledge and can be used in investigations?

Testimonial evidence is based on personal knowledge and experiences of an individual, often gathered through interviews or witness statements. This type of evidence derives from what someone has personally seen, heard, or knows, making it valuable in investigations as it can provide insights and firsthand accounts related to a case. Testimonial evidence can help establish facts, clarify events, and support other forms of evidence. In contrast, the other types of evidence, such as physical evidence, circumstantial evidence, or documentary evidence, do not necessarily rely on an individual's personal experience but rather on materials or documents that may provide supportive context for the investigation. Using testimonial evidence allows an investigator to gather perspectives and narratives that are crucial for understanding the context of an incident.