An Update on the Hazards and Risks of Forensic Anthropology,Part I: Human Remains

This work reviews the hazards and risks of practicing forensic anthropology in North America, with a focus on pathogens encountered through contact with unpreserved human remains. Since the publication of Galloway and Snodgrass' seminal paper concerning the hazards of forensic anthropology, research has provided new information about known pathogen hazards, and regulating authorities have updated recommendations for the recognition and treatment of several infections. Additionally, forensic anthropology has gained popularity, exposing an increased number of students and practitioners to these hazards. Current data suggest many occupational exposures to blood or body fluids go unreported, especially among students, highlighting the need for this discussion. For each pathogen and associated disease, this work addresses important history, reviews routes of exposure, provides an overview of symptoms and treatments, lists decontamination procedures, and presents data on postmortem viability. Personal protection and laboratory guidelines should be established and enforced in conjunction with the consideration of these data.     

Meeting a Forensic Podiatry Admissibility Challenge: A Daubert Case Study

This article is an introduction to the United States Supreme Court's standard of admissibility of forensic evidence and testimony at trial, known as the Daubert standard, with emphasis on how this standard applies to the field of forensic podiatry. The author, a forensic podiatrist, provided law enforcement with evidence tying a bloody sock‐clad footprint found at the scene of a homicide to the suspect. In 2014, the author testified at a pretrial hearing, known as “a Daubert hearing,” to address the admissibility of this evidence in court. This was the first instance of forensic podiatry being the primary subject of a Daubert hearing. The hearing resulted in the court ordering this evidence admissible. The expert's testimony contributed to the suspect's conviction. This article serves as a reference for forensic podiatrists and experts in similar fields that involve impression evidence, providing evidentiary standards and their impact on expert evidence and testimony.     

An Evidence‐Based Forensic Taxonomy of Windows Phone Communication Apps

Communication apps can be an important source of evidence in a forensic investigation (e.g., in the investigation of a drug trafficking or terrorism case where the communications apps were used by the accused persons during the transactions or planning activities). This study presents the first evidence‐based forensic taxonomy of Windows Phone communication apps, using an existing two‐dimensional Android forensic taxonomy as a baseline. Specifically, 30 Windows Phone communication apps, including Instant Messaging (IM) and Voice over IP (VoIP) apps, are examined. Artifacts extracted using physical acquisition are analyzed, and seven digital evidence objects of forensic interest are identified, namely: Call Log, Chats, Contacts, Locations, Installed Applications, SMSs and User Accounts. Findings from this study would help to facilitate timely and effective forensic investigations involving Windows Phone communication apps.     

Error and its Meaning in Forensic Science

The discussion of “error” has gained momentum in forensic science in the wake of the Daubert guidelines and has intensified with the National Academy of Sciences' Report. Error has many different meanings, and too often, forensic practitioners themselves as well as the courts misunderstand scientific error and statistical error rates, often confusing them with practitioner error (or mistakes). Here, we present an overview of these concepts as they pertain to forensic science applications, discussing the difference between practitioner error (including mistakes), instrument error, statistical error, and method error. We urge forensic practitioners to ensure that potential sources of error and method limitations are understood and clearly communicated and advocate that the legal community be informed regarding the differences between interobserver errors, uncertainty, variation, and mistakes.     

Forensic Biomechanical Analysis of Falls from Height Using Numerical Human Body Models*

Abstract: This article describes the method of using human body models developed originally for the use in automotive safety in forensic reconstructions of falls from height. The MADYMO^® software package and multibody human body models were used in forensic analyses of two real cases—a fatal fall from a window c. 13.8 m above the ground and a fall into a c. 2.5‐m deep cellar pit resulting in isolated ankle joint injury. The performed series of numerical simulations helped to reconstruct the events and to resolve legally relevant questions concerning various aspects of the falls. The benefits as well as limitations and potential biases associated with the use of numerical simulation in forensic biomechanical settings are discussed. The method has proven to be effective under specific circumstances, though the cost (both financial and temporal) still prevents it from wider use.     

Traceology,criminalistics, and forensic science

There is a serious issue within the forensic science community, which even extends outside of the field. The role of the scientist in the investigation of crime has been increasingly confined to the laboratory, which has been accompanied by the conflation of the terms forensic science and criminalistics. This unfortunate situation has been festering for years. To make matters worse, the era of the proactive, problem-defining, criminalist (generalist) is waning, and possibly over. Present-day “criminalists” are treated as little more than reactive, protocol-constrained, laboratory technicians, with few, if any, consequential crime scene roles. In most cases, these “criminalists” merely respond to routine requests from prosecutors and police. The absence of science at the front end of forensic investigations, i.e., the scene, has resulted in biased, ineffective, inefficient, and/or erroneous outcomes with immediate and long-term societal impacts. To disentangle this imbroglio, we propose the use of another term, traceology, which has seen limited use worldwide except in the field of archaeology. With respect to criminalistics, this term has been previously proposed by Margot (20–21). Traceology is an historical science, dealing with the examination, analysis, and scientific interpretation of event traces (signs or remnants) of earlier activities. In this commentary, we define and redefine familiar, but ambiguous, terms and concepts with the hope of recapturing the essence of criminalistics (32), which we suggest is best termed traceology.     

A Quantitative Assessment of Zygomatic Projection for Ancestry Estimation

Anterior zygomatic projection (ZP) is historically referenced as a useful trait in ancestry estimation, particularly when differentiating between Native Americans and U.S. Whites and Blacks. However, methods of assessing ZP vary, are susceptible to multiple interpretations, and have not been quantitatively validated. This study uses 228 3D surface scans of U.S. Whites, U.S. Blacks, and Native Americans to quantitatively test the ZP methods published by Rhine in 1990 (Skeletal attribution of race: methods for forensic anthropology, Albuquerque, NM, Maxwell Museum of Anthropology, 1990) and Bass in 1995 (Human osteology: a laboratory and field manual, Columbia, MO: Missouri Archaeological Society, 1995). Two ZP angles and two distances, representing method interpretations, were collected and analyzed via ANOVA and discriminant function analyses. Although significant ancestry differences were found across all variables, only the Bass inferior zygomatic distance successfully differentiated the pooled Native American group from pooled U.S. Whites/Blacks (73.7% correct). Arctic Native Americans, displaying the most projecting zygomas, are driving group differences. Significant overlap in measurement distributions were observed between groups in all variables, indicating limited forensic utility.     

Strengths,Limitations, and Recommendations for Instrumental Color Measurement in Forensic Soil Characterization

Color determination of soil evidence is often done by visual comparison to soil color charts. A handheld spectrophotometer was tested with representative materials for its suitability for forensic soil characterization. Instrumental colorimetry provides accurate colorimetry with ~10-fold better precision than a soil color chart. The minimum sample size for accurate color determination was between 0.02 and 0.04 mg of fine soil for the specific instrument tested. Reporting colors in the L*a*b* space permits quantification of ΔE₀₀, a measure of perceptible color difference, could enable objective quantification of small color differences and thresholds for forensic soil comparisons. A ΔE₀₀ greater than ~ 3.5 to 6 likely indicates disparate soil sources in a forensic comparison, in the absence of confounding factors like sample alteration. Despite the superior precision of instrumental colorimetry, this approach is inappropriate for samples which are mottled at an inseparable scale, attached to a substrate, or too small for instrumental measurement.     

Diurnal and Nocturnal Flight Activity of Blow Flies (Diptera: Calliphoridae) in a Rainforest Fragment in Brazil: Implications for the Colonization of Homicide Victims

Nocturnal flight of blow flies (Diptera: Calliphoridae) is a controversial issue in forensic entomology. We performed two field experiments to investigate the diurnal and nocturnal activity of six blow fly species in a rainforest fragment in Brazil. Initially, nocturnal (17:30–05:30) versus diurnal (05:30–17:30) flight activity was investigated. Only 3.9% of adults were collected at night, mostly the native species Mesembrinella bicolor, and nocturnal oviposition did not occur. In the second experiment, collection of adults took place at the following intervals: 05:30–08:30, 08:30–11:30, 11:30–14:30, and 14:30–17:30. The proportions of adults did not differ significantly among the four diurnal intervals, except for Hemilucilia segmentaria, which was captured more frequently in the early morning. Calliphoridae has predominantly diurnal behavior, not laying eggs in darkness. The association of the native species M. bicolor, Hemilucilia semidiaphana, and H. segmentaria to forested areas reinforces the forensic relevance of data on their flight pattern.     

DNA in the Criminal Justice System: The DNA Success Story in Perspective,

Current figures on the efficiency of DNA as an investigative tool in criminal investigations only tell part of the story. To get the DNA success story in the right perspective, we examined all forensic reports from serious (N = 116) and high‐volume crime cases (N = 2791) over the year 2011 from one police region in the Netherlands. These data show that 38% of analyzed serious crime traces (N = 384) and 17% of analyzed high‐volume crime traces (N = 386) did not result in a DNA profile. Turnaround times (from crime scene to DNA report) were 66 days for traces from serious crimes and 44 days for traces from high‐volume crimes. Suspects were truly identified through a match with the Offender DNA database of the Netherlands in 3% of the serious crime cases and in 1% of the high‐volume crime cases. These data are important for both the forensic laboratory and the professionals in the criminal justice system to further optimize forensic DNA testing as an investigative tool.     

Age Estimation Based on DNA Methylation Using Blood Samples From Deceased Individuals

Age estimation using DNA methylation levels has been widely investigated in recent years because of its potential application in forensic genetics. The main aim of this study was to develop an age predictor model (APM) for blood samples of deceased individuals based in five age-correlated genes. Fifty-one samples were analyzed through the bisulfite polymerase chain reaction (PCR) sequencing method for DNA methylation evaluation in genes ELOVL2, FHL2, EDARADD, PDE4C, and C1orf132. Linear regression was used to analyze relationships between methylation levels and age. The model using the highest age-correlated CpG from each locus revealed a correlation coefficient of 0.888, explaining 76.3% of age variation, with a mean absolute deviation from the chronological age (MAD) of 6.08 years. The model was validated in an independent test set of 19 samples producing a MAD of 8.84 years. The developed APM seems to be informative and could have potential application in forensic analysis.     

A Three‐Locus,PCR‐based Method for Forensic Identification of Plant Material

Plant residue is currently an underutilized resource in forensic investigations despite the fact that many crime scenes, as well as suspects and victims, harbor plant‐derived residue that could be recovered and analyzed. Notwithstanding the considerable skill of forensic botanists, current methods of species determination could benefit from tools for DNA‐based species identification. However, DNA barcoding in plants has been hampered by sequence complications in the plant genome. Following a database search for usable barcodes, broad‐spectrum primers were designed and utilized to amplify and sequence the rbcL, trnL‐F, and rrn18 genetic loci from a variety of household plants. Once obtained, these DNA sequences were used to design species‐targeted primers that could successfully discriminate the source of plant residue from among the 21 species tested.     

Identifying and measuring juror pre-trial bias for forensic evidence: development and validation of the Forensic Evidence Evaluation Bias Scale

Abstract

Previous research has provided support for the impact of juror pre-trial bias on judicial decision making, particularly in cases where the evidence presented at trial is of weak or ambiguous probative value. In an effort to identify whether a pre-trial bias for forensic evidence exists, the Forensic Evidence Evaluation Bias Scale (FEEBS) was developed and tested. The results of a principal components analysis suggested that two distinct constructs were being measured, corresponding to a pro-prosecution and pro-defence bias toward forensic evidence. In a second validation study, scores on these two subscales were compared with other existing juror bias measures (Juror Bias Scale and Belief in a Just World) and in a mock juror decision making task only the pro-prosecution subscale of the FEEBS predicted the perceived strength of forensic evidence. A partial mediation model is presented which explains the relationship between this bias and verdict preferences. The implications of this potential juror bias are discussed in the context of real juries, the CSI Effect (which refers to anecdotal claims that jurors are biased by the popularity of fictional representations of forensic science on television) and peremptory challenges, as well as future research directions.     

Investigating Residential History Using Stable Hydrogen and Oxygen Isotopes of Human Hair and Drinking Water

The relationship between isotopic signals in human hair and geographic region has potential forensic applications for identifying unknown individuals' place of recent residence. This study analyzes δ²H and δ¹⁸O isotopes in residential tap water and bulk hair samples from 17 volunteers representing 12 locations in Ontario, Canada. There is a strong correlation (R² = 0.9) between δ²H and δ¹⁸O values of the water samples. In contrast, the δ²H and δ¹⁸O values of the hair samples are weakly correlated (R² = 0.3), and the greater variability in the data is linked to dietary factors. This study demonstrates that the δ²H and δ¹⁸O values of hair and drinking water can be used to help identify potential place of residence in forensic cases, particularly in relation to proximity to large bodies of water such as the Great Lakes, but interpretations are complicated by the contribution of both water and diet to δ²H and δ¹⁸O values in hair.     

Soil Fungi: Their Potential use as a Forensic Tool

As a grave is an anomalous environment and differs from its surroundings, criminal investigators employ different techniques for locating, recovering, and analyzing clandestine graves. In this study were identified the fungi found in the soil under corpses in decomposition with an aim at relating the copresence of human remains and different fungal species. Were isolated the fungi in three ways: soil washing, serial dilutions, and moist chamber growth. Dichotomomyces cejpii, Talaromyces trachyspermus, Talaromyces flavus, and Talaromyces sp. were the representative species found—with those belonging to the ammonia group, whose fungi are the first in the succession of cadaver decomposition directly in the ground. The mycobiota found at the present study area clearly differs to mycobiota identified in control sample and from previously described species for other areas of Buenos Aires Province, Argentina. Further forensic examples of this type are needed to develop fully the detailed use of mycology as a forensic tool.     

The Effect of Flunitrazepam (Rohypnol®) on the Development of Chrysomya megacephala (Fabricius, 1794) (Diptera: Calliphoridae) and its Implications for Forensic Entomology

This study investigated the potential effects of flunitrazepam (known as “date rape drug”) on the developmental cycle of Chrysomya megacephala, an important forensic species, and their possible implications for the calculation of the PMI. A 1050 C. megacephala eggs were divided into five groups with seven replications each. The eggs were placed on artificial diet prepared with four drug concentrations of flunitrazepam (4, 8, 16, and 32 ng/g), besides the control group (prepared with water). Were evaluated the potential effects on development time, weight gain, and mortality during the cycles. The drug had no significant effect on development time or mortality although it did affect the weight of the pupae and adults (Kruskal–Wallis, p < 0.05). The result can be deduced that the determination of the postmortem interval is not affected.     

Bite Mark Analysis in Foodstuffs and Inanimate Objects and the Underlying Proofs for Validity and Judicial Acceptance

Even though one of the first bite mark cases was Doyle v. State in 1954 (a bitten cheese case), the research has focused on bite marks inflicted in human skin. As published Papers, Case Reports, or Technical Notes can constitute precedents which are relied upon in making the legal arguments and a considerable amount of case law exists in this area, we present a systematic review on bite mark analysis in foodstuffs and inanimate objects and their underlying proofs for validity and judicial acceptance according to Daubert rulings. Results showed that there is vulnerability in these procedures, and it is essential to demand for focus scrutiny on the known error rates when such evidence is presented in trials. These kinds of bite marks are well documented; however, there has been little research in this field knowing that the protocols of analysis and comparison are the responsibility of the forensic odontologists.     

Forensic Analysis of Explosives Using Isotope Ratio Mass Spectrometry (IRMS)—Part 1: Instrument Validation of the DELTAplusXP IRMS for Bulk Nitrogen Isotope Ratio Measurements

Abstract: A significant amount of research has been conducted into the use of stable isotopes to assist in determining the origin of various materials. The research conducted in the forensic field shows the potential of isotope ratio mass spectrometry (IRMS) to provide a level of discrimination not achievable utilizing traditional forensic techniques. Despite the research there have been few, if any, publications addressing the validation and measurement uncertainty of the technique for forensic applications. This study, the first in a planned series, presents validation data for the measurement of bulk nitrogen isotope ratios in ammonium nitrate (AN) using the DELTA^plusXP (Thermo Finnigan) IRMS instrument equipped with a ConFlo III interface and FlashEA? 1112 elemental analyzer (EA). Appropriate laboratory standards, analytical methods and correction calculations were developed and evaluated. A validation protocol was developed in line with the guidelines provided by the National Association of Testing Authorities, Australia (NATA). Performance characteristics including: accuracy, precision/repeatability, reproducibility/ruggedness, robustness, linear range, and measurement uncertainty were evaluated for the measurement of nitrogen isotope ratios in AN. AN (99.5%) and ammonium thiocyanate (99.99+%) were determined to be the most suitable laboratory standards and were calibrated against international standards (certified reference materials). All performance characteristics were within an acceptable range when potential uncertainties, including the manufacturer’s uncertainty of the technique and standards, were taken into account. The experiments described in this article could be used as a model for validation of other instruments for similar purposes. Later studies in this series will address the more general issue of demonstrating that the IRMS technique is scientifically sound and fit‐for‐purpose in the forensic explosives analysis field.     

Whole Plastome Sequences of Two Drug-Type Cannabis: Insights Into the Use of Plastid in Forensic Analyses

DNA is one of the fastest growing tools in forensic sciences, increasing reliability in forensic reports and judgments. The use of DNA has increased in different areas of the forensic sciences, such as investigation of plant species, where plastid DNA has been used to elucidate and generate evidence in cases of traceability of genetically modified and controlled plants. Even with several advances and the practice of using DNA in forensic investigations, there are just few studies related to the identification of genetic tools for the characterization of drug and nondrug-types of Cannabis. Herein, the whole plastomes of two drug-type Cannabis are presented and have their structures compared with other Cannabis plastomes deposited in the GenBank, focusing in the forensic use of plastome sequences. The plastomes of Cannabis sativa “Brazuka” and of the hybrid Cannabis AK Royal Automatic presented general structure that does not differs from the reported for other C. sativa cultivars. A phylogenomic analyses grouped C. sativa “Brazuka” with the nondrug C. sativa cultivars, while the hybrid Cannabis AK Royal Automatic placed isolated, basal to this group. This suggests that the analysis of plastomes is useful toward genetic identification of hybrids in relation to C. sativa.