Post-Mortem Interval Estimation Based on Insect Evidence: Current Challenges

Abstract

During death investigations insects are used mostly to estimate the post-mortem interval (PMI). These estimates are only as good as they are close to the true PMI. Therefore, the major challenge for forensic entomology is to reduce the estimation inaccuracy. Here, I review literature in this field to identify research areas that may contribute to the increase in the accuracy of PMI estimation. I conclude that research on the development and succession of carrion insects, thermogenesis in aggregations of their larvae and error rates of the PMI estimation protocols should be prioritized. Challenges of educational and promotional nature are discussed as well, particularly in relation to the collection of insect evidence.

Looking Back to Move Forward: How Review Articles Could Boost Forensic Entomology

“…On the contrary, development–time datasets, which are quite simple to perform and an indispensable prerequisite for aging larvae, have received little attention during the last years. In this Special Issue, Matuszewski [ 17 ] highlights the need for development datasets for potentially useful species that regularly breed on cadavers, but for which no reference developmental data are available. For those species with wide geographical distributions, local developmental studies are required as there might be differences in the developmental rates between populations.…”

“…For those species with wide geographical distributions, local developmental studies are required as there might be differences in the developmental rates between populations. In this context, Shin et al [ 18 ] present baseline developmental data for the blow fly species Lucilia sericata in South Korea, commonly used as a forensic indicator and for which development–time datasets from other geographical regions are available [ 17 ]. Regrettably, many researchers may be discouraged to perform basic developmental studies as they could sometimes be seen as “not innovative enough” for being published in some high-profile academic journals.…”

“…Regrettably, many researchers may be discouraged to perform basic developmental studies as they could sometimes be seen as “not innovative enough” for being published in some high-profile academic journals. In addition, as in the case of sample collection at the forensic scene, an updated review providing detailed and standardized rearing and sampling protocols for developmental studies would be highly beneficial and enable the comparison of different datasets [ 17 ]. Laboratory analyses have indeed demonstrated that numerous biotic and abiotic parameters such as food type, larval behavior or bacterial load, to name a few, could significantly affect larval development [ 19 ].…”

“…Even if there are some key areas where much research still needs to be carried out [ 17 ], forensic entomology is today a dynamic science, with the above-mentioned increasing number of scientific publications and active researchers and practitioners across the world. However, many other researchers and practitioners can face significant challenges if they approach this discipline for the first time.…”

“…That those opinions should be based on science means that they should rely both on a solid experience in the area and on related and published peer-reviewed studies. This emphasizes the importance of forensic entomology research, either if it consists of baseline studies stimulated by general needs (e.g., development–time datasets) or on ad hoc experiments simulating the conditions of a specific case [ 5 , 17 ]. On the other hand, this also highlights the need for self-criticism and awareness among researchers and practitioners of the limitations of the application of forensic entomology [ 29 , 30 ].…”