The use of a 3-D laser scanner to document ephemeral evidence at crime scenes and postmortem examinations

Proper documentation of physical evidence at both crimes scenes and postmortem examination is crucial for downstream analysis, interpretation, and presentation in court. Ephemeral or transient evidence poses particular challenges to investigators, as its very nature renders it difficult or impossible to seize and maintain in its original physical state. The use of a hand-held three-dimensional (3-D) laser scanner is proposed to capture and document such evidence, both in the field and at autopsy. Advantages of the scanner over traditional means of documentation such as photography or casting include the ability to obtain measurements in all dimensions, the ability to reconstruct missing elements, and the ease with which generated images can be interpreted by the jury at trial. Potential scenarios warranting the use of the scanner are identified, and the limitations of its use are discussed.     

The association of alcohol-induced blackouts and grayouts to blood alcohol concentrations

The primary aim of this study was to investigate the association between measured blood alcohol concentration (BAC) and the presence and degree of amnesia (no amnesia, grayout, or blackout) in actively drinking subjects. A secondary aim was to determine potential factors other than BAC that contribute to the alcohol-induced memory loss. An interview questionnaire was administered to subjects regarding a recent alcohol associated arrest with a documented BAC greater than 0.08 g/dL for either public intoxication, driving under the influence, or under age drinking was administered. Demographic variables collected included drinking history, family history of alcoholism, presence of previous alcohol-related memory loss during a drinking episode, and drinking behavior during the episode. Memory of the drinking episode was evaluated to determine if either an alcohol-induced grayout (partial anterograde amnesia) or blackout (complete anterograde amnesia) occurred. Differences in (1) mean total number of drinks ingested before arrest, (2) gulping of drinks, and (3) BAC at arrest were found for those having blackouts compared with no amnesia; while differences in drinking more than planned were found between the no amnesia and grayout groups. A strong linear relationship between BAC and predicted probability of memory loss, particularly for blackouts was obvious. This finding clinically concludes that subjects with BAC of 310 g/dL or greater have a 0.50 or greater probability of having an alcoholic blackout.     

The detection of clandestine graves in an arid environment using thermal imaging deployed from an unmanned aerial vehicle

The Middle East is one of the world regions that has frequently suffered from armed conflicts that resulted in mass burials. However, the detection of clandestine graves in such an arid environment by deploying remote sensing payload on unmanned aerial vehicles (UAVs) has received little attention. The present study used a UAV equipped with a thermal sensor aimed at narrowing down the search area of possible gravesites in the arid climate of Kuwait. The enclosed research area, which includes both control and experimental mass graves, was imaged for 18 months. The variation in topsoil temperature and soil moisture between the graves and their surroundings was evaluated. The results of the analysis demonstrated the effectiveness of thermal imaging techniques in detecting heat produced from buried sheep carcasses and detecting the change in grave soil moisture for our research environment for 7 and 10 months, respectively. The buried animals significantly influenced the topsoil temperature (p = 0.044), while the height from which the images were captured had an insignificant effect on the measured temperature within the range tested (p = 0.985). Furthermore, there was a negative correlation (−0.359) between grave temperature and the calculated soil moisture. The results from these cost- and time-effective search methods presented in this study confirm their potential for the detection of burial sites in an arid environment.     

The Death of Countess Agusta in Portofino (Northern Italy) and the Soil from Two Mismatched Slippers

Abstract:  Accident, suicide, or homicide might have caused the death of Countess Agusta who fell from the 80-m tall cliff of her villa. Two mismatched slippers were recovered along the cliff. Use was made of microscope, X-ray diffractometry, scanning electron microscopy, and microprobe techniques to compare 40 mg of soil collected from the slipper soles with samples from the villa garden. Structural details of the slipper soles were consistent with the lady wearing them during the fall. Analysis of the soil residues confirmed that they originated from the garden only. The features of a few, minute glass chips adhering to the slipper soles reasonably matched those of other fragments that were found on a small ledge on the cliff beyond the garden parapet. Based on this and other evidence, the case was closed with a verdict of accidental fall.     

The use of material culture to establish the ethnic identity of victims in genocide investigations: a validation study from the American Southwest*

Successful prosecution of genocide requires that the victims constitute one of four protected groups: national, religious, ethnic, or racial. Establishing victim identity in prior trials has relied on positive identification of decedents, been largely presumptive, or was based on untested methodology. This report details a validation study of one untested method: the use of material culture in establishing ethnic identity. Classes of clothing and personal effects were scored on 3,430 individuals of known Hispanic or White ancestry from autopsy records in New Mexico. Significant differences were seen in evidence of language, nationality, and religious affiliation between the two groups, as well as clothing types and currency. Predictive models used to estimate ethnic identity in random, blind subsets produced an overall accuracy of 81.5% and estimates of 61-98% in specific subsets. Results suggest material culture, when present, can provide reliable evidence of ethnic affinity in genocide investigations.     

Watch for those fragments of evidence: the use of an automatic timepiece to help correlate a helicopter crash site from the Vietnam War

This case study illustrates the use of the date function on an automatic wristwatch to help identify a Vietnam War helicopter crash site. The location of a crash incident can sometimes be uncertain because of inadequate or inaccurate wartime records and the passage of time. Artifacts recovered from a prospective crash scene are regularly used to correlate the loss incident. In this case study, a recovered automatic watch displayed a date 2 days later than the reported loss incident. Although the date conflicts with the aircraft crash incident report, it is observed that a fully wound automatic watch continues to work for c. 2 days after movement of the watch ceases. Thus, the watch's date in fact correlates with the aircraft crash incident report. It is noted that automatic watches may also be used to date scenes of crime.     

Three species of insects collected from an adult human corpse above 3300 m in elevation: a review of a case from Colorado

We report on the colonization of an adult human corpse by three insect species at 3350 m (11,000 ft) in elevation. The adult silphid Thanatophilus coloradensis (Wickham), adults of the blow fly Calliphora coloradensis (Hough), and larvae and adults of Lucilia silvarum (Meigen) were all collected from the victim's body which had been wrapped in plastic. The victim was found in late June in the Rocky Mountains of Colorado. This paper provides additional confirmation of the taxa utilizing a human corpse at high elevations in Colorado.     

Determination of Both Fetus’ and Mother's Blood Type from an Autopsy Case Immersed in Formalin for Over 50 Years

A female fetus which had been immersed in formalin for more than 50 years was found in Japan. Because no liquid blood could be obtained, we tried to use immunohistochemistry (IHC) methods to tissue samples obtained at autopsy to identify both the fetal and mother's blood type. We detected B antigens on endothelial cells in paraffin sections of the fetal organs. Furthermore, we observed both anti‐A‐ and anti‐B‐positive red blood cells in the intervillous space, which is indicative of the mother's blood type. To our knowledge, this is the first case report on determining the blood type of both the fetus and the mother from tissue immersed in formalin for such a long time. The results suggest that IHC is valuable for the determination of ABO blood type in circumstances of long postmortem duration and unfavorable storage conditions.     

The use of bloodhounds in determining the impact of genetics and the environment on the expression of human odortype

Bloodhounds are used to trail fleeing felons and missing persons. In order to start a trail, the dog must be presented with a person's scent. There are many hypotheses on what a bloodhound smells while trailing. The present study attempts to identify whether human scent is genetic, and if it is influenced by one's environment. Bloodhounds trained in human scent discrimination were used to differentiate between monozygotic twins, related and nonrelated persons, living together and apart. The first test required the dogs to run blind trails after being presented with the scent of one person in the pair, while the opposite person was hidden. The second test allowed the dogs to trail one person in the pair after both people were hidden. Results appear to demonstrate that bloodhounds rely heavily on genetic cues when differentiating between people. Environmental cues do not appear to significantly aid the bloodhound in scent discrimination.     

Seizures of Clandestinely Produced Tablets in Santa Catarina,Brazil: The Increase in NPS from 2011 to 2017

Ecstasy is the name given to a large group of substances known as “club drugs” traded in the form of tablets, powder and liquid that present a varied composition, including mainly 3,4-methylenedioxymethamphetamine (MDMA) and analogous substances, in addition to the growing presence of new psychoactive substances. Based on this, clandestinely produced tablets (“ecstasy tablets”) seized by police in Santa Catarina in the period from 2011 to 2017 were analyzed. During the study period, 3472 seizures occurred, which resulted in total 498,443 tablets seized. Seventy nine substances were identified. In the year 2011, about 90% of the tablets contained MDMA. This number decreased to 66.6% in 2017. On the other hand, there was an increase in the number of tablets that mainly contained synthetic cathinones, as well as tryptamine and piperazine derivatives. Police seizures in the metropolitan region of Florianópolis and on the coast prevailed over the rest of the state.     

The use of geographic information systems as a forensic tool to investigate sources of marine mammal entanglement in fisheries

Commercial fisheries represent a significant anthropogenic threat to marine mammal survival. Causes of marine mammal mortality are commonly determined by detailed necropsies of stranded carcasses. Gross evidence of entanglement in a fishery might include gear attached to the body, internal indications of asphyxiation and trauma, or gear markings on the epidermis. As gear is often fishery-specific, wound patterns on the epidermis that are created by entanglements in fishing gear may serve to identify possible sources of mortality. For this study, tools within the Environmental Systems Research Institute, Inc. (ESRI) ArcMap GIS software were used to create maps that outline impressions that fishing gear can leave on the epidermis of entangled marine mammals. These maps can subsequently be used to identify possible sources of fishery entanglement for the many marine mammals that wash ashore without gear attached to their carcass. Entanglement wound patterns can be visually compared with fishing gear characteristics; however, differences in scale and image quality can introduce subjectivity that might hinder source identification. The technique described herein provides an objective way to outline the unique characteristics of fishing gear and their associated wounds on entangled marine mammals. Additionally, spatial relationships are preserved as the maps are adjusted to varying scales. Whereas the initial protocol required time-consuming digitization of the outline and visual determination of the pattern interface, this new, semiautomated technique saves analyst effort and minimizes error.     

The typing of group-specific component (Gc protein) in human blood stains

It is known that the typing of group-specific component (Gc protein) in human blood stains is difficult since Gc protein of the extracts of blood stains migrates more anodally to the α₁-globulin region in agar-gel immunoelectrophoresis, while Gc protein in liquid blood normally migrates to the α₂-globulin region. We have reported that the Gc protein found in the α₁-region is the result of binding of actin to Gc protein (Shinomiya, K., Kimura, H., Yoshida, K., and Shinomiya, T., J. Biochem., 92 (1982) 1163–1171, which renders it difficult to determine the Gc-phenotypes in the blood stains. On the basis of the above findings, we developed the method of phenotyping the Gc protein of human blood stains by agar-gel immunoelectrophoresis. Since the binding activity of actin to Gc protein is lost after treatment with a high concentration of guanidine HCl, the extracts of blood stains were treated with 4 M guanidine HCl to dissociate Gc protein and actin and then dialyzed to remove guanidine HCl. By this method we are able to determine the phenotypes of Gc protein in blood stains. The method we have developed is a useful tool in the forensic laboratory.     

The application of miniplex primer sets in the analysis of degraded DNA from human skeletal remains

A new set of multiplexed PCR primers has been applied to the analysis of human skeletal remains to determine their efficacy in analyzing degraded DNA. These primer sets, known as Miniplexes, produce shorter amplicons (50-280 base pairs (bp)) than standard short tandem repeat (STR) kits, but still utilize the 13 CODIS STR loci, providing results that are searchable on national DNA databases. In this study, a set of 31 different human remains were exposed to a variety of environmental conditions, extracted, and amplified with commercial and Miniplex DNA typing kits. The amplification efficiency of the Miniplex sets was then compared with the Promega PowerPlex 16 system. Sixty-four percent of the samples generated full profiles when amplified with the Miniplexes, while only 16% of the samples generated full profiles with the Powerplex 16 kit. Complete profiles were obtained for 11 of the 12 Miniplex loci with amplicon sizes less than 200 bp. These data suggest smaller PCR amplicons may provide a useful alternative to mitochondrial DNA for anthropological and forensic analysis of degraded DNA from human skeletal remains.     

Prevalence and blood concentrations of benzodiazepines and opioids in opioid-positive death investigations in Ontario,Canada, from 2017 to 2021

The aim of this study was to investigate the incidence of benzodiazepines in opioid-positive death investigations, including trends in frequency and combination of drugs, as well as demographic data and blood concentrations, where available. Additionally, naloxone concentrations in polysubstance compared to opioid-only cases were analyzed. This was a retrospective study that consisted of all post-mortem toxicology cases in Ontario, Canada, from January 01, 2017, to December 31, 2021, with an opioid finding in any analyzed autopsy specimen. There were 11,033 death investigations identified. The overall rate of benzodiazepine co-involvement was 54.5%. Males accounted for the majority of cases (71%), and the most affected age group was 30- to 39-year-olds. The most frequently detected opioid was fentanyl and the most frequently detected benzodiazepine was etizolam, which was also the most frequently observed opioid/benzodiazepine combination. Findings related to differences in concentrations of opioids when naloxone was also present were mostly non-significant, except for methadone. The rate of benzodiazepine detection with opioids grew faster than opioid detections overall, potentially due to the increasingly toxic drug supply. Detection of novel psychoactive drugs fluctuated more unpredictably than opioids and benzodiazepines associated with clinical use. These findings can help inform policy decisions by public health agencies in exploring harm reduction efforts, for example, education and drug-checking services.     

The Fatal Poisoning Pattern of Ankara (Turkey) and Nearby Cities from 2007 to June 2011: A Retrospective Study in Forensic Autopsies

We aimed to obtain an outline of the nature and number of fatal poisonings which still appear to affect widely the population in Turkey. A total of 5921 forensic autopsies were performed between 2007 and 2011 in Ankara and nearby cities and 366 of them were fatal poisonings (219 male, 147 female). Most of the cases were between 41 and 60 years old (n = 84). Most of the fatalities were reported during winter months (48.1%). Carbon monoxide exposure was the most common reason (66.7%) within all the causes followed by medicine and narcotics (13.9%). Postmortem blood alcohol concentrations in ethyl and methyl alcohol poisonings were 385.1 ± 61.9 and 206.8 ± 138.9 mg/dL, respectively. The most common location of deaths was home (71.3%). Fatal poisonings have been a growing global problem because of some shortcomings about the socioeconomic conditions and increasing illicit drug abuse. The level of education, socioeconomic conditions, and legal approaches are very important for the prevention fatal poisonings.     

The use of simulated crime scenes in teaching undergraduate forensic sciences: Implementing an active learning approach to forensics

Incorporating a simulated crime scene into one’s pedagogy in forensic science undergraduate courses allows students the opportunity to experience a realistic scenario while demonstrating their knowledge and enhancing their critical thinking skills. The purpose of this paper is to examine an active learning approach to using simulated crime scenes to provide an impactful learning experience for students. While potentially challenging for the instructor, constructing a crime scene scenario can provide students with hands-on practical experience while helping to dispel forensic science misconceptions. Through many years of creating crime scenes, best practices for using such high impact activities in forensic science courses are described in detail, including preparatory exercises that culminate in the final crime scene scenario, considerations in preparing and constructing a crime scene activity, and supervising and assessing students once the activity begins. Three major challenges to implementing active learning exercises such as simulated crime scenes in undergraduate forensic science programs include high workload for instructors, limited supplies, and lack of suitable facilities. Workload solutions include instructors and departments considering the cost and benefit of course releases to improve curriculum and student enrollment. Supplies and facilities solutions involve innovation in reuse and repurposing of supplies, and instructor flexibility in using classroom and outdoor spaces.     

The Use of a Sequential Extraction Technique to Characterize Soil Trace Evidence Recovered from a Spade in a Murder Case in Brazil*

Soil trace evidence can be useful in criminal investigations. A homicide which had occurred in South Brazil been concluded through the courts with a guilty conviction. A spade with soil traces adhering to it was seized from the confessed killer's house, it having been established that it had been used to bury parts of the victim's body. In the context of this confession, it provided an opportunity to test a protocol of analysis and verify the potential of discriminate soil sample analysis in such case works. This allowed us to test the practice of sequential analysis which had been developed for forensic case works in Brazil, with three sequential extractions: (i) 0.2 mol/L pH 3.0 ammonium oxalate; (ii) dithionite–citrate–bicarbonate; and (iii) 0.5 mol/L NaOH. It was possible to predict the sequence of events related to the homicide by using the sequential extraction technique and to conclude that: (i) the A horizon soil from the burial location of the torso was found to be very similar to the soil samples which had been recovered from the spade, which was able to be established despite there only being a small amount of soil adhering to the spade; (ii) the location where the legs were buried contributed a low amount of soil adhering to the spade. Therefore, it is suggested that, where possible, sequential extractions should be prioritized from a questioned sample to best provide information about the likely sequence of contact places and this test likely scenarios and criminal events.