Which of the following is NOT a fundamental issue in a death investigation?

In a death investigation, the fundamental issues typically revolve around understanding the circumstances surrounding the death and establishing the facts related to the victim. Victim activity pertains to the actions and behaviors of the deceased prior to death, which can provide significant context for investigators. Postmortem changes refer to the biological changes that occur after death, which are crucial for determining the time of death and understanding the physical state of the body. The cause of death is a critical aspect, as it identifies the medical explanation for why the individual died, which is central to the investigation.

Circumstantial evidence, while important in many investigations, is not a fundamental issue in the context of establishing the basic facts of a death investigation. It can provide context or support certain conclusions but does not directly inform investigators about the death itself, such as victim activity, postmortem changes, or the cause of death. Thus, the focus of a death investigation is more directly tied to the other three issues than to circumstantial evidence, making it the correct choice for what is not deemed a fundamental issue in this specific context.