(Forensic Science) Officer Piddington has been called to a murder scene. He arrives to find EMTs tending to the victim lying on the living room floor with a large knife protruding from his sternum. It is clear that this is where the crime occurred, and Officer Piddington does not see any evidence of dangerous chemicals on site. He secures the area and then begins to document the scene. What is one of the first things that Officer Piddington records in his notes about the crime scene?

The victim's past criminal history
A description of the crime scene when he arrived
The estimated time of death of the victim
A list of possible suspects involved in the crime