Forensic Investigations in the Saanich Inlet

In a homicide, knowing the time a person died is vital to the police investigation. When a person has been dead for more than a few days, it is very difficult for a pathologist to determine time of death. It is then that the police turn to forensic entomologists to interpret the insect evidence on the body to estimate time of death. Insects can be used to estimate elapsed time since death from a matter of hours after death to a year or more. Forensic entomology is now an accepted and well-known part of a police investigation. Much research has been conducted on land to understand the sequence of insects that colonize a body. However, very little is known about what happens to a body when the murder victim is dumped in the ocean.

VENUS in Saanich Inlet offers a perfect research environment in which to observe what happens to a dead body over time when submerged. This experiment was designed to simulate a homicide in which the body of a murder victim is weighted down and sunk in the Inlet. Such research results can be used in a police investigation and eventually presented and challenged in court. Therefore, it is important to use a scientifically accepted animal model to simulate the human body. Pig carcasses are recognized worldwide as the best mimic of a human body. They have skin very similar to humans (even used in skin grafts), they have gut bacteria close to ours as they are also omnivores, they are relatively hairless, and a small pig is roughly equivalent to the human torso.

A dead pig carcass was purchased from a butcher and deployed by ROPOS at a depth of 94 meters, in front of the VENUS Saanich Inlet Camera. Using the camera, the carcass is examined at any time of the day and night to identify not only the arthropod and vertebrate fauna that is attracted to the remains, but also the types of wound pattern which they produce. This is also valuable when human remains are recovered as it gives us an idea of what marks on the body may relate to anthropophagy (animal scavenging) and what may relate to the homicide. We can also understand any water chemical changes that may occur locally, either due to the carcass itself, or to the increased fauna in the vicinity using the VENUS instruments.

Not only will this experiment provide invaluable data for use in homicide investigations, but it will also provide data for studies on marine ecosystem responses to rich nutrient inputs.

Prof. Gail Anderson, School of Criminology, Simon Fraser University

Click here to access the image gallery from the experiment. If you don’t want to see a pig carcass being dismembered, DO NOT follow this link. If you do, remember that the pig was humanely dispatched.

Clip 1: VENUS CMAP camera records Dungeness Crabs on the pig. August 8th, 2006, Saanich Inlet CMAP camera.

Clip 2: VENUS CMAP camera records Squat Lobsters picking bones clean. August 16th, 2006, Saanich Inlet CMAP camera.