Search for hidden targets

Regardless of the type of crime and the methods of intervention on a crime scene, the forensic geoarchaeologist starts from a fundamental approach, common to all geosciences, which is to study, know and interpret the environment and the territory in which the crime itself took place. This is because the forensic geoarchaeologist must be able to seek and collect adequate information from the environment to place it in the specific criminal context and in its dynamics, effective and presumed. In particular, this approach, in the first instance, involves the use of different analysis tools at different scales and totally non-invasive. 


Methodologies

If, starting from the macro scale, aerial or drone photographs and multispectral satellite images can easily provide information to limit the area to be investigated thanks to the morphological or vegetational changes of the terrain (the so-called remote sensing or remote sensing), geophysics, at microscale, allows the localization and mapping of objects (e.g. metal drums), bodies (e.g. burials) or cavities (e.g. bunkers), of various nature and size, obliterated underground or underwater (generally, in forensic geophysics the use of electromagnetic instruments, such as georadar or metal detector, is involved).

The ability of remote sensing to be able to scour large areas reducing the use of human resources, the possibility of containing intervention times and being able to operate in disadvantaged and / or dangerous conditions for rescue teams allows this tool to be implemented and assisted with other geophysical tools (such as georadar, Lidar, etc.) and with other disciplines (such as forensic archaeology and, more generally, forensic geosciences) for conducting search operations for hidden targets.

The geophysical approach requires specialization and experience. In fact, the development of the tools, the knowledge and understanding of the subsoils of the area to be investigated, the ability to process and interpret the data collected are fundamental elements for the success of the geophysical campaign, in particular in the forensic field. If the acquisition of georadar data might seem trivial (in reality it is complex and delicate too), its interpretation requires years of experience and countless studies.

In addition, those who commission this geophysical investigation (be it the judge, the police, the prosecutor or the lawyer) must know not only the potential of the instrument but also its limitations. It is not a magic wand, but a scientific instrument that as such has uncertainties in the measurement that must be taken into account when acquiring and interpreting the data.

To work in the forensic field, basic geoarchaeological skills must be far beyond school skills. This includes not only knowing perfectly the techniques of excavation, but also those of pre-excavation investigation (cartography, soil analysis, and remote sensing) and post-excavation. The most important factor, therefore, is that the geoarchaeologist has a large base of experience. These challenges highlight a key theme, namely the need for flexibility and experience across a vast range of site types. Forensic work is not the right place to be initiated. In these contexts, the work proceeds at too fast a pace to learn slowly and the result is too important to risk beginners making mistakes on the site.

In general, the development of a geophoran approach that uses different contexts of spatial analysis (i.e. from the satellite macroscale to the localized microscale) can help to investigate the interrelationships between the various protagonists, both active and passive, of a crime. For this reason, it is not possible to have a single analysis environment and the tools necessary to investigate correctly must necessarily be functional to the exploration and understanding of the interconnections between the crime, the crime scene, the victim and the criminal.