What type of evidence would a witness provide if they observed someone igniting gasoline?

A witness who directly observes someone igniting gasoline is providing direct evidence. This type of evidence is characterized by firsthand observations that are factual and do not require inference or interpretation. In this case, the witness's account of the action—seeing a person actively ignite gasoline—serves as a direct observation of the event and can be used in court or investigations to establish what happened.

Direct evidence is critical in legal and investigative contexts because it provides a clear and direct link to the event in question, making it more impactful than other types of evidence. For example, unlike circumstantial evidence, which relies on evidence that suggests a fact but does not prove it outright, direct evidence confirms an event because it is based on the witness's personal experience.