Which type of evidence involves direct observation by the investigator?

The type of evidence that involves direct observation by the investigator is personal observation. This form of evidence is based on what the investigator directly sees, hears, or experiences during the course of an investigation. It allows the investigator to gather firsthand information that can be crucial in understanding the context and circumstances of a case. Unlike other types of evidence, such as documentary or testimonial evidence, which rely on external sources or accounts, personal observation draws from the investigator's own direct experience, making it a powerful tool in fraud examination.

In contrast, documentary evidence consists of written or recorded materials such as contracts, emails, and financial statements that can provide important information but are not based on direct observation. Testimonial evidence involves statements made by witnesses or participants, which are subject to interpretation and may not reflect the actual situation as clearly as direct observation would. Physical evidence refers to tangible items, such as tools or objects, which while important, do not involve the investigator's direct witnessing of an event or behavior.

Therefore, personal observation stands out as the most immediate and direct form of evidence in investigative work, helping to establish facts and context based on what the investigator personally experiences.