Journal of Forensic Research

The National Research Council (NRC) released a report in 2009 discussing the “science” used in forensics. Specifically, the report outlined concerns regarding the state of the forensic sciences and what was needed to raise the level of rigor and reliability of these fields in a court of law. In response to this NRC document, the present paper examined several parameters used in decomposition studies that have implications for forensic entomology. Specifically, this analysis was conducted to determine the degree of repeatability in methods across studies as related to general conclusions drawn in court, entomology and forensic investigations. Forensic entomologists primarily analyze insect evidence recovered from decomposing remains to estimate a portion of the Period of Insect Activity (PIA), which encompasses the time of colonization, to infer a minimum Postmortem Interval (PMI). One method utilized by entomologists relies on succession data from published studies to generate estimates of the minimum PMI of a decedent. For this article, approximately 75 publications on arthropod succession on vertebrate carrion were reviewed for 13 criteria that are known to play instrumental roles in governing this process: 1) animal model, 2) time of actual death, 3) euthanasia method, 4) storage method, 5) storage time, 6) time of removal from storage to placement in the field, 7) time of day remains placed in the field, 8) catalog of arthropods associated with the remains over time 9) time of initial insect contact, 10) time of initial colonization (i.e., arthropod offspring located on the remains), 11) study site, 12) number of replicate carcasses and 13) months and season of study. These criteria were selected as they can directly impact arthropod colonization and succession patterns on vertebrate carrion and are easily recorded. Data indicated that such information is highly fragmented, and that key criteria necessary to repeat studies (a core principle of the scientific method) are often lacking in the published literature. As an example, among the studies included in this analysis, we could not find significant associations between arthropod taxa richness and carcass model or carcass size. In the case of carcass size, island biogeography theory predicts that larger areas/resources will hold higher diversity. We suspect that the high degree of reporting variability in taxonomic resolution and taxa-specific study focus precluded such relationships that have been reported for other disciplines of biology. Consequently, we suggest that, to date, because of these issues there has not been a comprehensive analysis (e.g., meta-analysis) to provide general inference of arthropod succession patterns on carrion to predict a minimum PMI. In order to begin standardizing such studies, we suggest that future research endeavors examining arthropod succession on carrion record detailed data for all of the suggested criteria. Doing so can result in data amassed over time for use in comprehensive and strong meta-analyses. Such results could allow for greater appreciation of variation associated with arthropod succession on carrion.

Teeth can be used as a weapon of attack or defense. Dentistry has much to offer to law enforcement agencies in the uncovering and solution of crime. The permanent teeth develop throughout the first two decades of life, and physiologic variations, pathologies, and effects of dental therapy may be recorded in the hard tissues of the remaining dentition throughout life and beyond. It is the role of the dentist to help extract this information and use it in the identification of the unknown body. Human teeth and dental restorations have proven to remain stable during a long time as well as in extreme situations such as fire. Therefore, dentist can play an important part in the identification of severe mutilated bodies of unknown persons. The teeth may also be used as weapon and, under certain circumstances may leave information as to the identity of the biter. Analysis of bite marks is the second major responsibility of the forensic dentist. The general practitioner has a major role to play in providing the accurate dental records on which much of forensic activity is based.

According to the Study Group on Forensic Age Diagnostics (AGFAD), the radiological evaluation of third molar mineralization is a major criterion for chronological age estimation of living individuals. This investigation studied third molar development in 329 orthopantomograms (40.4% males) of Portuguese individuals, patients of Dental Medicine Faculty of Lisbon University, with an age range between 14,0 to 22,8 years, through five different methods (Demirjian, Haavikko, Harris and Nortjè, Kullman and Solari). The results show a better correlation, between real and estimated age, in Demirjian and Solari methods. Demirjian method was used to analyse the other results statistical variables. Third molar development occurs earlier, in average 9 months, in males, in stages D-G. In stage H there’s no significant difference. There’s no significant difference between mineralization of molars in the same arch, however, in the inter-arch comparison, the maxillary molars have a premature development, statistically different in stages F (males), G and H. The age 18 is reach in stage G and H, respectively, by females and males. Under the Portuguese Penal Code, section 19, the age is one of the factors of exceptional of criminal responsibility. For criminal pursuit, they state being minor than 16 years of age. This limit is reached for both sexes in the stadium F. However in any stage we can deduce the majority or minority in relation to the age of criminal responsibility. New studies about the influence of socioeconomic and genetic factors, in third molar development, are necessary.