Under what condition is testimonial evidence considered valid?

Testimonial evidence is considered valid when it is provided by a competent witness under oath. This is because the oath serves as a formal commitment to tell the truth, which is essential for maintaining the integrity of the legal process. By being under oath, the witness understands the seriousness of their statements and the legal ramifications of lying, which adds a layer of credibility to the testimony. Moreover, "competent" refers to the witness having the capacity and legal ability to provide evidence based on their knowledge or experience regarding the matter at hand. This ensures that the information presented is not only sworn to be true but comes from a trustworthy and knowledgeable source.

In contrast, the other options do not necessarily imply validity. Documentation in a report does not equate to the witness's firsthand knowledge or their obligation to tell the truth, and not all reports are created equally or carry the same weight as sworn testimony. While law enforcement officers can provide valuable information, their presence alone does not validate the testimony unless they are also sworn witnesses to the relevant facts. Finally, public acknowledgment does not imply that the individual making the statement has the requisite knowledge or is legally bound to tell the truth, and thus may lack the necessary credibility.