Faculty Research Spotlight
“The best practices and protocols produced during this project will provide search and recovery teams with easily understood, flexible recommendations for detecting and documenting outdoor crime scenes.”
As a forensic anthropologist, I am frequently called upon to assist in death investigations. Locating and documenting outdoor crime scenes containing human remains is often a necessary first step. However, traditional methods for locating clandestine bodies of deceased individuals are time and resource consuming and can lead to accidental alterations of the scene before it is fully documented. Small unmanned aerial systems (UAS), popularly called drones, equipped with various sensors may provide a cost- and time-effective method for obtaining accurate, reliable, and high resolution spatial and spectral (color) output. This output can be put to good use in locating and documenting potential scenes when searching large geographical areas.
To this end, I have teamed up with the following people: Dr. Derek Anderson and doctoral student Bryce Murray, engineers at the University of Missouri and experts in algorithm development and remote sensing; Gene Robinson from GRC, Inc., a Federal Aviation Administration (FAA) certified drone pilot who frequently conducts searches for human remains; and local law enforcement. We quickly realized there was a need for evidence-based standard protocol for using UASs with remote sensing to detect and document outdoor crime scenes.
Our project, funded by the National Institute of Justice, seeks to develop evidence-based best practices and protocol for search and recovery teams as well as a graphical user interface that uses algorithms to automate image analysis and identify potential hotspots for further investigation. The best practices and protocols produced during this project will provide search and recovery teams with easily understood, flexible recommendations for detecting and documenting outdoor crime scenes. In addition, algorithms will enhance UAS productivity for identifying sites that have clandestine human remains, which will benefit law enforcement and may contribute to FAA policy regarding the use of UASs for search efforts.
Our initial research has indicated that UASs equipped with sensors using different spectral wavelengths (e.g., infrared, near-infrared, and ultraviolet) can help locate clandestine human remains either buried in the ground or on the surface of the ground. When bodies begin to decompose, the activities of bacteria and insects can generate enough heat or thermal energy to make the bodies detectable with a UAS using an infrared sensor. Likewise, buried remains can be detected with the thermal spectrum at sunrise and sunset because the grave soils heat up and lose heat differently than the surrounding soils. In cases where the body is on the ground surface but scavenged and scattered, the near-infrared spectrum can detect the organically rich soil produced as fluids leak from the body during decomposition (known as the cadaver decomposition island or CDI) for several years. Near infrared is ideal for detecting slight differences in the health of vegetation on the grave because the body has an effect on the plant community. New plants growing in the grave soil will differ from surrounding vegetation in species diversity and then later in lushness for several years. Finally, ultraviolet light is ideal for detecting bones since they fluoresce.
In addition to locating human remains, drones can be used to conduct pre-processing assessment and nondestructive documentation of the scene in 2D or 3D prior to anyone entering the area. Drone images can provide an overall aerial view or survey to determine the scene boundaries and the state of the human remains, document the spatial relationship between the remains and other evidence, and possibly detect other associated evidence prior to inadvertent disturbance caused by personnel entering the scene. Drone technology is well established in law enforcement, but by adding strong evidence-based protocols this technology has the potential to revolutionize the search and documentation of clandestine human remains. When equipped with different sensors, drones provide an additional tool for law enforcement to systematically and safely search for clandestine remains. The ultimate goals of this project are to aid the criminal justice system, help bring justice to crime victims, and help provide closure for families of victims.