Which of the following best defines testimonial evidence?

Testimonial evidence is best defined as statements made under oath by witnesses. This type of evidence carries significant weight in legal proceedings, as it involves firsthand accounts of events related to the case. The reliability of testimonial evidence can be enhanced by the fact that witnesses are sworn to tell the truth, thereby adding a layer of accountability to their statements. This is crucial for the judicial process, as the credibility of eyewitness testimonies can impact the outcomes of trials.

The other options do not accurately represent testimonial evidence. For example, statements made by experts fall under a different category known as expert testimony, which relies on specialized knowledge rather than personal observations. Written documents submitted to court belong to documentary evidence, which consists of physical records rather than oral accounts. Lastly, physical items collected from a crime scene are known as physical evidence, which includes objects, materials, and other tangible items, distinct from the verbal accounts provided by witnesses. Each of these types of evidence plays an important role in a trial, but they do not fit the definition of testimonial evidence.