By Brett A. Phaneuf and Peter W. Hitchcock
*This article is reproduced from the Spring 1999 edition of
Underwater Magazine, pages 75-77 as a public service to the police and public
safety diving community*
Federal, state and local law enforcement agencies, fire departments and military personnel are often called on to assist in the location of drowning victims and in the forensic recovery of human cadavers deposited in a body of water. Currently, there is no standard practice or methodology for the location and forensic retrieval of cadavers and evidence that will assist law enforcement and military personnel in investigating events that led to a body's being underwater. The most daunting problem is to locate the cadaver itself, a task which is frequently dangerous as well as expensive and time consuming. It is not uncommon that dive rescue teams will search in vain for a drowning victim. This is not a condemnation of dedicated rescue personnel; it is a testament to the difficulty of their task. More often than not, eyewitnesses cannot pinpoint where a drowning victim was last seen, or exactly where a vehicle entered the water. Dragging with hooks is generally unreliable and time consuming, and "cadaver dogs" can become confused in an area with a high degree of composting materiel (i.e. swamps) and by immersed baited traps.
With the advent of the personal computer, global positioning systems, and advances in acoustic imaging, the task has been made somewhat less arduous. However, few rescue organizations or law enforcement agencies possess this equipment or the trained personnel to send into the field. Additionally, there has been no scientific study of how the natural decomposition, position, disarticulation, clothing, etc. of a submerged cadaver will effect the image or data produced by remote sensing devices.
The Submerged Forensic Recovery Study (SFRS), established at Texas A&M University, Department of Oceanography in the fall of 1998, is attempting to establish a baseline data set of acoustic images of cadavers in various stages of decomposition due to immersion in water. Data will be analyzed and used to train law enforcement and rescue personnel to recognize cadavers with remote sensing equipment, gather what amounts to a crime scene photograph before divers contaminate a site, and to develop a methodological framework for the recovery of cadavers under various conditions. The goals are to provide an added margin of safety for divers, assist in the apprehension of criminals, and help determine cause in a multiple fatality event such as an aircraft crash. It will also provide relief to grieving family members of a victim by recoverying their loved one expediently.
SFRS personnel are available to local, state and federal agencies to assist in the location and recovery of drowning and murder victims and to respond to multiple fatality events, participating in as many recovery efforts as fiscally and physically possible in Texas and surrounding states. Information gathered in the course of these efforts will form the core of the data collected by the study. To that end, a group consisting of rescue personnel and graduate students will be trained at Texas A&M University to deploy state-of-the-art acoustic imaging devices (side scan and sector scanning sonar systems) to assist in actual recovery efforts.
The high-resolution sonar systems are essentially an outgrowth of geophysical oceanography exploration equipment designed to map features of the seafloor. With the recent emphasis on counter-mine warfare, higher frequency and higher resolution sonar systems have been manufactured. As recently as five years ago the resolution of these instruments was not adequate for a study like SFRS. However, the crossover of medical technology pioneered by Marine Sonic Technologies, Ltd, to undersea acoustic imaging arrays dramatically increased the resolution for low-reflectance targets like immersed cadavers. However, these devices still have not been widely accepted or utilized, largely due to a lack of awareness and training.
Side scan sonar systems are generally comprised of a towfish, tow cable, and recording device-in this case, a personal computer. As the towfish is towed through the water, acoustic pulses are sent out and reflected by the seafloor and objects on it. These reflections are processed into an image similar to an aerial photograph and stored on a personal computer. Coupled with a global positioning system, this is a powerful instrument for large area searches. Generally speaking, one sonar team on a small boat can scan an underwater area the size of a football field and identify cadavers in five minutes, a task that would take the most proficient dive team weeks to accomplish.
Sector scanning sonar systems are similar to side scan systems in that they both emit high frequency pulses of ultrasound; however, a sector scanning device is usually stationary and rotates its emitting array through a field of view of about 90 degrees. These systems are also coupled to GPS and PC systems and store all the data digitally with position information. Scanning sonar is especially useful in confined spaces and mounted to a robotic vehicle, although the resolution is not equal to that of the side scan sonar. To augument the potential for locating cadavers, images generated by sonar devices can be reanalyzed and enhanced repeatedly in order to observe detail that may be faint or obscured by some acoustic effect.
The National Emergency Rescue and Response Training Centre (NERRTC), established by the Texas Engineering Extension Service (TEEX), in the aftermath of the 1995 bombing of the Alfred P. Murrah Building in Okahoma City, is located on the Texas A&M campus, making the university the ideal site from which to conduct marine forensic research. NERRTC integrates the well-established emergency response training programs and facilities of TEEX into a major training centre for domestic response to acts of terrorism caused by weapons of mass destruction (WMD). Currently the centre provides training to 38,000 Emergency First Responders annually, from all 50 states and U.S. territories and 35 nations worldwide. SFRS personnel will provide training to NERRTC personnel and trainees at the TEEX facility on the A&M campus.
The National Forensic Sciences Technology Centre was established by the American Society of Crime Laboratory Directors in 1995 and began operating in July 1996. It is an independent nonprofit organization that offers services to support general and DNA laboratory accreditation and provides continuing education programs and support to academic programs. NFSTC will serve as a liaison for the Submerged Forensic Recovery Study to the forensic community at large and be responsible for the dissemination of new information gathered in the course of the research.
Construction of a a marine forensic training and research facility at NERRTC is presently in the planning stages. In a shallow lake at NERRTC facility, several cars, trucks, and boats will be immersed and wired with high resolution, low light camera systems. The vehicles will be outfitted with cadaver simulators in various dress, position, and orientation within the vehicle. Rescue personnel will be able to practice extracating cadavers from these simulators in relative safety. The many cameras will allow training personnel to videotape the recovery and provice postive feedback. Something as simple as a shoelace caught on a gear shift can be an immensely difficult obstacle to overcome when removing a cadaver from a vehicle in the real world. Practice on an assortment of vehicle configurations and under varying degrees of difficulty could ultimately save the lives of rescue personnel. Several training seminars are being considered that will aquaint trainees with the tools at their disposal.
Unfortunately, there are many organizations and persons at large proclaiming themselves to be masters of new recovery techniques and technologies, only to charge the community, or grieving family, outrageous fees for little or no service. Basic training similiar to that listed above will allow rescue personnel to ask insightful questions and effectively determine if a proposed approach to a problem is feasible and likely to produce results.
As an adjunct to the training element and field recovery efforts outlined above, forensic research will also be conducted. Although it may sound gruesome, cadavers will be submerged in a segregated portion of the research area. As the cadavers decompose they will be repeatedly imaged with a high-resolution side scan sonar device, scanning sonar, and a scanning laser imaging device until only stable osteological material is left available for continuing imaging. Range, grazing angle, aspect and orientation of the device with respect to the cadaver will be periodically varied. Data will also be collected with chemical sensors in place over the cadaver deposition site and biological analysis will be performed on water samples taken in proximity to the cadaver. This more or less controlled data will then be compared with field data to help refine the instruments used in recovery and the process. No study of this type has been conducted and any data gathered will be an advance.
In addition to work and research focused on the recovery imaging of cadavers, the study will also focus on various forensic questions, such as: What effect do various types of clothing have on images? In suspected homicide cases, does debris scattered in, on or around a depostion site contain information leading to a cause of death other than drowning, and how can divers best recover? Is is possible, to some degree based on position of the cadaver, to determine if drowning was the likely cause of death before the divers inadvertently contaminate a site? Can high-resolution imaging devices be used to detect explosives to forestall terrorist actions on and around the water? Or in the aftermath of a terrorist or weapons of mass destruction attack, can we determine cause, origin, dispersal pattern of an explosion and assist in the apprehension of the perpetrators? With such diverse questions facing us, the continued input from law enforcement, rescue personnel, and forensic researchers will be greatly beneficial in the design of a new questions and future research topics.
As an invaluable addition to this research program, many consultants from the private sector and academia have offered their expertise. Two of the most notable are Mark Atherton (Kongsberg Simrad Mesotech. Ltd), an expert in the interpretation of acoustical data and deployment and operation of sector scanning and multi-beam sonar systems, and Martin H. Wilcox (Marine Sonic Technology Ltd), widely recognized as the inventor of real-time imaging obstetric ultrasound equipment and revolutionary high-resolution, low cost undersea imaging equipment. Mr. Wilcox possess unparalleled knowledge concerning the imaging of tissue in all contexts; the SFRS greatly appreciates his support.
Result and Conclusions
This study and training program is essential in order to generate a coherent plan of action, or methodology, for the retrieval of cadavers and evidence underwater. Full implementation will provide access to the basic technological tools law enforcement personnel require to efficiently locate, recover and study, in a forensic manner, submerged crime scenes, and multiple fatality events. New instruments will be tested and recommendations made for the improvement of existing technologies, and a detailed methodology will be produced on CD-ROM and disseminated by the National Forensic Science Technology Centre (NFSTC).
Quarterly publications and updates will be released through the NFSTC to relevant law enforcement organizations and research facilities to raise awareness of technologies available to rescue personnel working on or under water. Additionally, monthly training sessions will be arranged for military, federal and state law enforcement personnel at Texas A&M University under the auspices of the National Emergency Response and Rescue Training Centre (NERRTC).
At the conclusion and throughout the study, results will be made available free of charge. Data will be managed in a state-of-the-art Geographic Information System (GIS), allowing for immediate access to critical data and expedient reorganization of the date to suit an individual researcher or investigator. It has framework within which to expand the study and add variables not initially incorporated into the research design. This study will directly benefit all branches and levels of local, state, and federal law enforcement agencies, as well as the military, by making the task of cadaver retrieval expedient, safe and possible where it may not have been before.
Although the Submerged Forensic Recovery Study is based in Texas, the geographic range of its activities will not be limited soley to that region; requests for assistance of the SFRS will be considered from all 50 states of the union. Decisions about the recovery efforts to assist will be made in consultation with NERRTC and NFSTC. Priority will be given to the location of the remains of law enforcement officials and in the recovery of evidence that may be of assistance in homicide investigations. Recommendations from the Technology Assisted Search Team of the Federal Bureau of Investigation for assistance in homicide investigations will also be given priority. In order to gather broad data relevant to a greater number of law enforcement agencies and officials, the SFRS will also actively seek to participate in recovery efforts in diverse environments or in areas that present particular challenges to the team.
The SFRS is still seeking additional funding. Parties interested in helping or needing more information should contact:
E-mail:bphaneuf @ ocean.tamu.edu
E-mail:pwhitch @ tca.net
Phaneuf and Hitchcock are students in the Departmentsof Oceanography and Anthropology, Texas A&M University. Until recently, Phaneuf was employed by Marine Sonic Technology Ltd, where a considerable amount of his time was spent assisting law enforcement agencies with the location of submerged cadavers. An aptitude for sonar interpretation, coupled with survey skills acquired while working as an archaeologist, led to great success in recovery efforts. Recognizing the desperate need for further research in submerged forensic research, Phaneuf returned to Texas A&M University to study for his doctorate in the submerged forensic study of decomposition of human cadavers.