Substance Detection Golden Retrievers: Human Remains

Human Remains Detection (HRD) canines, also sometimes referred to as 'cadaver dogs', are trained to locate the scent of human decomposition and alert the handler to its location; whether it be on land, under water, or buried.

HRD dogs search for victims who have died as a result of natural or man-made disasters, drowning, suicides or other means. There are additionally Forensic HRD teams that specialize in locating trace evidence and residual scent. This team has been taught to search homes, vehicles and property without causing damage or disturbing the integrity of a crime scene. That is, dogs are taught not  to disturb the crime scene by digging or attempting to retrieve evidence. Dogs are also taught how to search homes or vehicles without causing any harm to the property. These dogs are taught to discriminate between human and all other non-human items, and tend to work in a slow and methodical fashion. Their most common alerts are passive, that is, by sitting or lying down when an item is found.

Specially trained Forensic Evidence Dogs or Human Remains Detection Dogs are used for: cases involving buried bodies, old cases, bone searches, blood evidence searches, residual scent searches, crime scene searches, building searches, and vehicle searches.

A must-have, wonderful article that provides a great background for understanding human scent detection is this: Specialized Use of Human Scent in Criminal Investigations.

What is the difference between a search dog, cadaver dog, decomp dog and a forensic evidence dog?
We have found that there is no standard terminology for describing various disciplines, specific search tasks that canines are trained to perform. Therefore, we propose and use the following terminology:

Search DogA general term referring to a canine trained for searching based upon visual, olfactory, or auditory clues. This would include the disciplines of: area search dog, trailing search dog, cadaver search dog, decomp search dog, disaster search dog, water search dog, forensic evidence search dog and human remains detection dog.

Area Search Dog This dog is trained to cover or grid large geographic areas by sampling the air currents for traces of human scent. The dog searches and samples the air currents by ranging/quartering back and forth through the area that is assigned to the team. This dog is sometimes referred to as "Wilderness Search Dog or "Air Scent Dog" which is another general description of many search dogs. Some area search dogs are also scent specific. They work from a scent article to search for the person that matches the scent article, ignoring all other humans in the area.

Trailing DogA canine with the specific ability and training to track/ trail and locate a specific human on the basis of scent.

Cadaver Dog A narrow term, used in a search-and-rescue context, to indicate a canine primarily trained as a trailing or area search dog that has also received cross training in the location of dead human bodies.

Decomp Dog The term "decomposition dog" was started by the NecroSearch group. They felt it better describes how dogs will indicate decomposed human scent which includes blood, feces, urine or other material with human scent on it.

Forensic Evidence Dog A general term that can describe several different kinds of specialties. Include but not limited to firearms, weapons, articles or scent discrimination. There are some people that describe Human Remains Detection Dogs as Forensic Evidence Dogs.

Water Search DogA dog trained to locate dead bodies under water. This can be done from a boat or as a shoreline search.

Human Remains Detection Dog This Detection Dog is a specialist and has never been trained to look for live humans. They specialize in crime scenes, old cases, small scent sources and residual scent. These dogs have been trained to exclude fresh human scent along with all other animal scents.

What are the qualities and skills of a HRD / Forensic Evidence Dog?  
The Human Remains Detection Dog is trained to alert on residual scent along with other faint scent sources like dried blood. The dog is taught not to disturb the crime scene by digging or retrieving evidence. An important skill the dog is taught is how to search homes or vehicles without causing harm to property. The dog is taught to discriminate between human and all other non-human items. The dogs usually work more slowly and more methodically.

My dog is trained for search and rescue, can I also teach him to do forensic evidence work? 
Yes! Dogs are capable of understanding several disciplines at the same time. Potential problems are: dogs trained in disaster must be very clear and have a different alert for live and dead, occasionally dogs trained in both live and dead scent will alert and we are unable to determine which of the two they have alerted on. As the need for forensic evidence dogs increases we see more handlers who are training specialty dogs. They feel that a dog that has been imprinted on one type of scent is more accurate that a cross trained dog.

Is evidence searching the same as forensic evidence? 
Terminology gets confusing, people use different words to mean the same thing or the same word to mean different things. We define evidence searching as an article with live human scent on it. Forensic evidence searching can be cadaver, decomposing human scent, or any body fluids from a deceased person. These scents can be on an article, the actual body, in the ground or residual. The main point is a forensic evidence dog is never looking for live scent.

From the Institute for Canine Forensics, a non-profit organization in Northern California for the advancement of research and education of Forensic Evidence and Human Remains Detection Dog teams.

There are also Historical Human Remains Detection Dogs. Under the umbrella of Institute for Canine Forensics, the Historical Grave Detection Group has been formed by several Forensic Evidence and Human Remains Detection Dog teams. According to HRD dog handlers Adela Morris, Shirley Hammond and Eva Cecil, using dogs to help locate historical or archaeological graves is a new concept. These dogs are trained to be slow and methodical and keep their noses just above the surface of the ground. The reason for this is that with any fast moves, the dog could miss a grave. This is not an easy task, many years of slow and patient training required to develop the requisite skills. Yet, training the dogs is only one part of the challenge of this type of Historical Human Remains Detection work.

These dog handlers must also learn about different kinds of soils, historical cemeteries, history, growth rates of trees and plants, and more. To take an example, consider the soil conditions in many areas in California. The varying conditions make grave searching quite challenging due to the adobe clay. In winter, this heavy clay soil becomes saturated with water thus trapping the fragile scent. And, during the summer, the clay soil becomes very hard which creates different search problems. You can learn more about this fascinating area through the Institute's DVD which documents various human remains detection dog activities. It is actually offered as a gift with a tax-deductible donation. Just email the Institute to request further information.

Explore and Learn More

    Articles and Print Resources

    Web Resources

      Crime Scene Guidelines for HRD Dog Handlers or Forensic Evidence Dog Handlers
      Residual Scent in Buildings .
      Forensic Evidence Canines - Status, Training and Utilization .
      Canine Stress and how to handle it
      Box Effect
      Above ground noninvasive technique to locate human remains and historical graves:
        The nose knows
      A Noninvasive Method of Searching for Buried Human Remains
      "Is there a human signature in ancient bones that a trained canine can recognize?"
      Canine Remote Sensing Detection - The Bayley Project

      K9 Forensics Discussion Group
      Cadaver Scent Project
      Canine Specialized Search Team  

TaleTell: Your own Stories of  Human Remains Detection Goldens
Meet some hard-working 4-footed detectors. And, if you have a Human Remains Detection Golden tale to tell, just send it, along with photos, to: