Fingermarks are important forensic evidence for identifying people. In this work, luminescent MOF [Eu(BDC)(HO)] (herein referred as EuBDC) was tested as a potential latent fingermark (LF) luminescent developer powder and its acute toxicity evaluated following OECD protocol 423. The results showed that the powder can develop groomed LF on materials such as leather, plastic, metal, glass, cardboard, and aluminum. LFs aged up to 30 days, left on glass slides were developed and classified as level-3. The images presented high quality, enabling correct donor identification as well as through an Automated Fingerprint Identification System (AFIS) search. EuBDC also showed useful results as secondary technique for fixed cyanoacrylate LFs, especially on a reflective, multicolored and non-flat surfaces. Additionally, the EuBDC was tested on ungroomed fingermarks, developed on a split depletion series of successive deposits and compared to a commercially available luminescent powder. Development also occurred on ungroomed aged fingermarks; as a secondary technique for cyanoacrylate fuming; and on transparent adhesive tape when used as a suspension for the latter. Considering that development powders are frequently handled by Papilloscopists and that this may pose a health risk, the acute toxicity and of EuBDC and histopathological analysis were evaluated. The tests showed no signs of toxicity. Therefore, the EuBDC was classified in category 5 in the Globally Harmonized System classification, the least toxic category, with an LD >5000 mg/Kg. The set of results shows that EuBDC powder has the potential use as a fingermark developer, as well as being suitable for applications for non-toxic material.

In recent years, there has been a significant increase in metal prices, particularly precious metals. Consequently, property crimes involving metal theft, including the theft of auto parts and catalytic converters, have also increased dramatically. The surge in catalytic converter thefts is linked to the use of precious metals, such as palladium, rhodium, and platinum, in their construction and their high price. A skilled thief can easily and quickly steal the catalytic converter by getting underneath the vehicle and, in a few moments, simply cut the exhaust pipes in front of and behind the catalytic converter using a common cutting tool, such as a reciprocating saw. Beyond the high price and the ease of committing the theft, police investigators experience difficulties finding forensic evidence that will incriminate the suspect. Furthermore, linking the cut items, such as the reciprocating saw, is not a simple challenge because of its mode of operation. The cyclic movement of the saw's blade, back and forth, removes a section of material. Therefore, examining a saw mark is mainly based on details relating to class characteristic features rather than individual characteristics. The authors seek to challenge this approach and demonstrate the feasibility of linking, using microscopic toolmarks comparison, cordless reciprocation saw, and the potential individual marks that may have resulted from the tip of its blade on the catalytic converter during the cutting action.

Of the various rules establishing a mental health clinician's legal duty to take precautions to protect their patient from harming others, the most common is the specificity rule that limits the protective duty to warn reasonably identifiable victims. The specificity rule is important wherein the main or only specified protective measure is warning the victim. In the last quarter century, Pennsylvania adopted the specificity rule from its Supreme Court Emerich decision. In its recent Maas decision, the Pennsylvania Supreme Court expanded the duty to apply to potential victims who are unnamed and unidentifiable except for living on the same floor as the patient of a multiunit building. Victims constituted a group referenced by the patient as a "neighbor," but from the patient's threats both narrower "next door neighbor" and broader "anyone." We place this judicial expansion of the duty to warn within the context of professional ethics guidelines and state Tarasoff statutes that pertain to psychiatrists. The potential adverse consequences of this vague expansion of the specificity rule for clinicians, psychiatric patients, and unconnected citizens of Pennsylvania and for other jurisdictions in which courts could misguidedly follow this expansionist example are discussed, along with potential solutions.

In shooting incident reconstructions, forensic examiners usually deal with scenes involving short-range trajectories, typically ≤30 m. In situations such as this, a linear trajectory reconstruction model is appropriate. However, a forensic expert can also be asked to estimate a shooter's position by reconstructing a long-range trajectory where the bullet's path becomes arced as a result of gravity and the greater time in flight. In this study, the point mass model (PMM) was used, because it is accessible and considered sufficiently accurate. A computer program using PMM can perform long-range trajectory reconstructions starting from an impact point. The reconstruction results in an area where the shot is expected to be fired from, not a single location. This is caused by varying the input parameters of the PMM. The aim of this study is to assess the accuracy of the method and discuss the influence of the most relevant parameters. The model has been validated by comparing its performance with 20 handgun bullet trajectories that were determined using Doppler radar measurements over long ranges, i.e. from 500 m to 1800 m. Comparison between the area calculated using the model and the actual shooter position demonstrates the limits of these reconstructions, particularly at high incident angles. The differences between the reconstructed deflections and the deflections measured by the tracking radar are rather large. This phenomenon is caused by either measurement errors in the cross wind as a function of height or inaccuracy of the radar's deflection measurements.

Decedent positive identification via visual comparisons of frontal sinus radiographs is commonly used in the medicolegal field; however, only a handful of studies have empirically tested this method. This study aimed to test the accuracy of visual assessment in frontal sinus identifications across a large and experientially diverse participant sample. A Qualtrics survey presented participants with 25 pairs of cropped frontal sinus radiographs, asking them to determine if they matched and their confidence level. Radiographs were from the American Association of Orthodontics Legacy Collection. Eighteen radiographic pairs were of the same individual taken a year or more apart. Seven pairs were from different individuals (nonmatches). Euclidean distances were used to select challenging nonmatches with similar outlines. Participants were also asked questions about their profession, training, and experience. The overall accuracy of the 145 respondents (3625 comparisons) was 89.9%, with a median accuracy of 92.0%. The majority of respondents (64.58%) report zero radiographic identification experience. Incorrect responses were biased, with only 3.6% of nonmatches wrongly reported as matches (false positives). Statistical analyses revealed significant effects of profession, radiographic experience, and training on match accuracies and confidence levels (p < 0.05), with a significant correlation between accuracy and confidence level (r = 0.302, p < 0.001). These results support the use of frontal sinus visual comparisons in forensic identifications but highlight the importance of training and experience. In practice, accuracy rates are expected to exceed those reported here, given that identifications are made by medicolegal personnel using higher quality radiographs of the entire cranium.

The house fly, Musca domestica, L. (Diptera: Muscidae), is a filth fly that is often associated with criminal and civil investigations surrounding abuse, neglect, and death of humans and other vertebrates. However, development data, which are crucial for determining the age of immatures collected under forensically relevant circumstances, are limited. Given the lack of data and the recognition of population-specific growth patterns, the aim of this study was to generate data for development of a M. domestica population from Texas, USA, on decomposing lean pork at 24.0°C (i.e., approximate room temperature in Texas) and 37.0°C (i.e., approximate human body temperature). As expected, fly development significantly differed between temperatures with development at the higher temperature taking significantly less time (development from egg to adult emergence occurred c. 48.5% faster at 37.0°C than at 24.0°C). The value of this dataset is demonstrated through an applied comparison with previously published data for the house fly. Differences in development times across life stages for the studies are evident, with shorter time of colonization estimations using the data published by Wang et al. (2018), especially in later life stages. These data represent the first development dataset for the house fly on decomposing flesh in North America. Furthermore, the comparison with the previously published dataset demonstrate data from this study are of value for future forensic investigations in Texas or possibly other parts of the United States where this species is encountered, as they can be used to determine time of colonization.

A piece of paper submitted as evidence can both have fingermarks with a high and low amount of sweat. When such paper is treated with 1,2-indanedione/zinc and subsequently heated at 160°C for 10 s, fingermarks with high sweat content may become overdeveloped. Attempts to prevent overdevelopment by reducing the heating time to <10 s were ineffective. However, it was found that maintaining the heating time at 10 s and reducing the temperature to below 160°C effectively prevented overdevelopment. In forensic practice involving latent fingermarks on actual evidence, an effective enhancement technique involves initially placing approximately 15 sheets of paper between the sample and an iron preheated to 160°C, and then applying heat for 10 s. This is subsequently followed by a secondary heating without the paper. This procedure has proven effective in enhancing fingermarks with both high and low sweat contents.

Immunolabeling based on fluorescence is a new technique that has been recently applied in the field of forensic science. In this paper, a new immunofluorescence method based on signal amplification was applied to develop fingermarks and improve the quality of pattern recognition with clear ridge details and high contrast. The high affinity between biotin and avidin and the one-to-many binding mode can connect several fluorescent groups together to achieve a signal amplification effect. The results indicated that the fluorescence intensity of the fingermark sample, as displayed by the biotin-avidin signal amplification system (BAS), was nearly three times higher than that revealed by previous immunolabeling methods based on fluorescence. Specifically, more fluorescent chromophores were bound to the friction ridges in BAS. Two proteins were selected as experimental target proteins for fingermark immunofluorescence visualization to optimize the visualization effect. The results showed that compared to keratin 1, dermcidin as the target protein in BAS achieved a more desirable effect, with 88.9% of the experimental samples left on nonporous objects having identification value. This method provides new insights for the development of fingermark spectra and is expected to become an effective and safe technology in the field of forensic science.

Microbial communities associated with the human body are highly dynamic and reflect the host environment and lifestyle over time. Studies show death is no exception, with data demonstrating similar antemortem and postmortem microbiomes up to 48 h following death. These predictable microbial biomarkers can inform death investigation by helping to estimate the postmortem interval and build models to identify cause and manner of death. However, no attempts have been made to model potential microbial biomarkers in pediatric (≤2 years) deaths. This study provided a cross-sectional survey of the microbiota of 53 pediatric cases (black, white, both sexes) seen in Wayne County, Michigan. Autopsy cases represented accidents, homicides, or natural causes. Postmortem microbiome were collected by swabbing the eyes, ears, nose, mouth, umbilicus, brain, rectum, trabecular space, and cardiac blood. 16S rRNA sequence analyses indicated that sex, race, age, body site, and manner of death (MOD) had significant effects on microbiome composition, with significant interactions among MOD, race, and age. Amplicon sequence variants identified intra- and interhost dispersion of the postmortem microbiome depending on death circumstance. Among manners of death, non-accidental deaths were significantly distinct from all other deaths, and among body sites the rectum was distinct in its microbial composition. There is a real need for robust postmortem microbiome before it can be standardized as a practical tool for use in forensic investigation or public health. These results inform postmortem microbial variability during pediatric death investigation that contributes to a larger effort to understand the postmortem microbiome.

In the case of a young woman's death by falling from the window of her boyfriend's sixth-floor apartment, investigators needed to determine whether the fall was suicidal or if the victim was forcibly pushed. The incident occurred at night, with her boyfriend being the only witness to how the fall happened. Establishing the origin of the material traces found on the woman's stockings and shoes, along with other clues, played a crucial role in resolving this dilemma. The traces found on the stockings and samples collected from the building's external wall were analyzed using digital stereomicroscopy, High-resolution scanning electron microscopy (HRSEM) coupled with energy dispersive X-ray spectroscopy (EDX), and optical microscopy. Chlorophyll presence on both the victim's stockings and the surface of the building façade was confirmed using Raman spectroscopy. The inorganic traces found on the shoes and the external wall were examined using stereomicroscopy and HRSEM coupled with EDX and were found to be similar in texture and elemental composition. The correspondence between the biological structures and mineral fragments, along with the dynamic friction marks found on the woman's body and shoes, confirmed physical contact between the victim and the external wall. These findings led to the conclusion that the victim struggled for her life and the fall resulted from a criminal act.

Fire is often used to conceal or destroy evidence of violent crimes, making it essential to understand how fire environments affect forensic evidence, particularly bloodstain patterns. This study investigates the impact of high heat environments and fire on the morphology and analysis of bloodstain patterns. Using controlled fire exposure, bloodstains were analyzed pre- and post-fire exposure on various substrates, including glass, painted drywall, and painted plywood. Measurements of angle of impact (AOI) and area of origin (AOO) were conducted using Faro Zone 3D Expert software. Despite physical alterations due to extreme temperature exposure, certain characteristics of the original bloodstains persisted. AOI calculations showed minimal deviation between pre- and post-fire measurements, with standard deviations generally under two degrees. AOO estimations also demonstrated no substantial statistical differences between pre- and post-fire data. The study confirms that bloodstain patterns retain observable traits despite exposure to high heat conditions, supporting the reliability of BPA in fire-affected scenarios. These findings enhance the understanding of bloodstain behavior in fire environments, aiding forensic investigations in accurately analyzing bloodstain patterns in cases involving fire or high-temperature conditions.

People diagnosed with substance use disorder (SUD) might represent a high-risk subpopulation for New Psychoactive Drugs (NPS) consumption, and hair analysis offers a unique perspective to assess drug prevalence in this population. The present study aims to assess the prevalence of NPS and their co-consumption with traditional drugs of abuse (DoA) in individuals diagnosed with SUD. Hair samples from patients under care at the addiction treatment service of Bologna, Italy, for a diagnosed SUD, were collected during 2023 and analyzed by ultra-high-performance liquid chromatography-mass spectrometry (UHPLC-MS/MS), using a previously validated method. Among the 88 patients included, 95.5% tested positive for at least one substance, of which 88.1% for traditional DoA only, and 11.9% for NPS in addition to DoA. Among the positive samples, patients were found positive for more than two drugs in 67.9% of cases. The combination of DoA and NPS was more frequent in the younger age group (<21-30 years old, compared to 31-70, p = 0.025). Ketamine was detected in 8.0% of all samples, with mean hair levels 49.68 pg/mg (ranging 8.55-81.90 pg/mg) and was frequently accompanied by cocaine (85.7% of cases). Fentanyl was detected in 3.4% of all samples, while, among NPS, buphedrone was the only one detected. Our retrospective study highlights that the consumption of NPS is relatively low compared to other vulnerable or high-risk populations. However, the prevalence of polydrug consumption and the high rate of ketamine-cocaine combination warrant careful monitoring even in this population.

Linear regression (LR) models that use cranial dimensions to estimate facial soft tissue thicknesses (FSTTs) have been posited by Simpson and Henneberg to assist craniofacial identification. For these regression equations to work well, the independent (craniometrics) and dependent (FSTTs) variables must be tightly correlated; however, such relationships have not been routinely demonstrated for adult humans. To examine the strength of these relationships further, this study employed magnetic resonance (MR) imaging to unambiguously measure cranial dimensions and FSTTs for 38 adult cadavers. This contrasts with prior published use of (a) spreading calipers to compress the face in an attempt to measure cranial dimensions through the soft tissues of the head and (b) needle puncture to measure the FSTT (a + b = legacy methods). To provide direct comparisons to prior work, this study also conducted legacy measurements for reproducibility tests. Previously published LR models were not supported by either the legacy or MR data. In the MR data, correlations between the cranial dimensions and FSTTs were generally weak with a mean absolute r = 0.13 and r range = -0.40 to 0.33. Compared to previously published arithmetic means, LR models did not improve FSTT estimates in the MR sample (SEE for LR = 5.5 mm; SEE for arithmetic mean = 5.2 mm). Using the latest MR imaging technologies, these results underscore prior warnings that cranial dimensions hold weak correlations with FSTTs and possess limited utility for improved FSTT estimation over and/or above arithmetic means.

Three-dimensional (3D) measurement systems for firearm forensics are becoming more prevalent in forensic laboratories, and these instruments are typically coupled with algorithms to assist firearm examiners with comparisons. Due to differences in firearm feature reproducibility on different types of ammunition, comparison algorithms need to be tested utilizing a variety of ammunition brands. For this study, 30 shots were fired, utilizing six common ammunition brands, from each of the 10 casework firearms for a total of 300 cartridge cases. All cartridge cases were scanned on a Cadre Forensics TopMatch-GS 3D desktop system and compared using Cadre's breech face and firing pin aperture shear algorithms for a total of 44,850 comparisons. Receiver operating characteristic (ROC) curves and the area under the curve (AUC) were used to quantify the performance of the algorithms when comparing within and between ammunition brands. Same ammunition brand comparisons (AUC = 0.964) performed statistically significantly better (p = 0.0075) than different ammunition brand comparisons (AUC = 0.944). Overall, the results generally indicated greater reproducibility of characteristics from a firearm when the ammunition in a comparison is the same, however, Cadre's algorithms demonstrated excellent overall discrimination between same and different-source comparisons regardless of ammunition brand (AUC = 0.946). Additionally, score thresholds were evaluated for easier interpretation of what algorithm results mean for practitioners, where 68.6% of same-source comparisons resulted in a similarity score greater than 0.5. These results should assist the field in moving toward the use of algorithms to assist examiners in casework comparisons.

Postmortem identification through fingerprints often encounters significant challenges, particularly with damaged epidermal tissue, due to factors such as carbonization, putrefaction, mummification, or saponification. Traditional techniques frequently fall short in cases involving fragile skin, which complicates the collection of clear fingerprint impressions. This study presents and evaluates an adaptive modification of the transillumination technique, integrating it with moistened black volcano powder to enhance fingerprint recovery from compromised postmortem tissue. A retrospective comparative analysis was conducted on 55 cases processed at the Ricardo Gumbleton Daunt Institute of Identification, São Paulo, Brazil, from January 2012 to May 2022. Of these, 12 cases with both pre- and post-treatment records were selected, totaling 28 distal phalanx samples. The proposed technique involved applying moistened black volcano powder to the epidermis, followed by transillumination and direct photography. The enhanced technique demonstrated a significant improvement in fingerprint quality. Qualitative analysis revealed that all samples treated with moistened black volcano powder clearly presented visible ridges and minutiae, whereas four samples treated with traditional transillumination alone were insufficient for minutia marking. Quantitative analysis indicated that 75% of the samples scored +2 (greater minutiae details and contrast), with an additional 25% scoring +1 (slightly better minutiae details and contrast). The combined use of transillumination and moistened black volcano powder significantly improves the visualization of postmortem fingerprints, providing a reliable method for forensic identification in cases with fragile or compromised epidermal tissue from putrefied or carbonized skin. This technique generates high-resolution fingerprint images that are suitable for database comparison and forensic analysis.

Early detection of submerged bodies is essential to increase the possibility of recovery. Different water bodies present different challenges, particularly rivers and the ocean, where chances of detection are vastly reduced. Modern recreational fish finders incorporate multiple sonar technologies, including Sidescan sonar, at high-frequency resolutions, similar to commercial units. Recreational units are widely available and usually hull-mounted, allowing them to be utilized on almost any vessel in shallow and difficult to navigate environments. Recreational fish finders are currently an untapped resource which may assist search teams with the early detection and recovery of human remains submerged in shallow water (<20 m). This research investigated the efficacy of a modern recreational fish finder attached to a kayak to detect human proxies and living human volunteers submerged at shallow depths in (1) two indoor freshwater environments and (2) two outdoor environments (a freshwater lake and a nearshore coastal environment). Results demonstrated that recreational fish finders can detect human bodies submerged in both fresh and saltwater contexts at shallow depths within the water column and on the water bottom. Recreational units equipped with Sidescan sonar (800 kHz) provided the necessary resolution for underwater body detection at shallow depths. These sophisticated sensors are currently used by recreational boaters and anglers, and offer the opportunity to increase the eyes in the water not just by search and recovery teams, but by the public itself.

This study follows up on previous research conducted by Litavec (J Forensic Sci., 68, 2023, 1780) on sorting commingled sacroiliac joints using deviation analysis. In the present report, the results of this technique are expanded to separating commingled first tarsometatarsal and atlantoaxial joints. Following the methods of Litavec (J Forensic Sci., 68, 2023, 1780), virtual models were created at the University of Tennessee-Knoxville Donated Skeletal Collection from 69 atlases and axes, 66 first metatarsals, and 64 medial cuneiforms using an EinScan-Pro 2x+ Handheld Surface Scanner. The shape and congruency of the articular surfaces were analyzed using a deviation analysis in Geomagic Wrap 2021. Receiver operating characteristic curves were conducted on reference samples composed of 200 commingled and non-commingled bone pairs per joint to identify threshold values for sorting the remains. Validation samples of 225 pairs were subsequently analyzed to identify the efficacy of this method on a sample of unknown individuals. The statistical analyses confirmed that deviation analysis values from commingled first tarsometatarsal and atlantoaxial joint pairs were significantly larger than those from non-commingled individuals (p < 0.0001). 87%-92% of first tarsometatarsal pairs and 63%-66% of atlantoaxial joint pairs were correctly sorted based on the selected threshold values. This study increases the number of joints able to be sorted by deviation analysis and reemphasizes its value as a technique for resolving commingled human remains.

Aggressive chemicals intended for cleaning pools or unclogging drains contain high concentrations of dangerous compounds, leading to their nefarious use in dissolving human remains in some criminal cases. The use of these readily accessible household cleaners to destroy human remains and hide evidence of a crime presents a considerable challenge for human identification. However, research on the success of recovering DNA from such remains is limited. Therefore, we investigated the effects of submerging partial human remains (including whole heads, forearms, and hands) in five different household products: bleach, Rid-X® septic treatment, lye drain opener, sulfuric acid drain opener, and muriatic acid (hydrochloric acid) pool cleaner. We evaluated the impact of each chemical, focusing on visual changes, DNA recovery, and the potential for successful human identification through traditional STR or mitochondrial DNA analyses. Exposure to all chemicals altered the appearance of the remains, but DNA recovery was still possible across various time periods, up to 28 days. Human remains exposed to bleach, Rid-X®, and lye produced full STR profiles after 4 weeks. Sulfuric acid shortened this time to 3 weeks, while hydrochloric acid, the most damaging chemical, limited full STR profile recovery to just the first 3 days of exposure. This study demonstrates that although differences in the rate of damage occur depending on the amount of tissue introduced, volume of chemical used, and the specific chemical of choice, DNA-based human identification of remains treated with everyday household cleaners is likely, particularly if bone fragments are recovered.

Accurate population and sex-specific normative values for the orbital and ocular dimensions, including the position and protrusion of the eye relative to the orbital rim, are vital for reliable facial approximations. In studies utilizing cadaveric tissue and computed tomography scans, the observed measurements may be influenced by desiccation, distortion or gravity, respectively. This study assessed the dimensions of the eye and orbit and established the position and protrusion of the eye relative to the orbital margin using cone beam computed tomography (CBCT) scans to negate the effect of gravity in the supine position. Scans of 197 adult South Africans (45 Black females, 49 Black males, 55 White females, and 48 White males) were selected retrospectively from private and public hospitals in Pretoria, South Africa. Linear distances were calculated from three-dimensional landmarks placed on the orbital rim and ocular equator using the MeVisLab © v.3.0.2 software. White females presented with significantly larger orbital heights and axial lengths of the eyes compared to Black females, while the eyeballs of Black females protruded more from the superior and lateral orbital margins. Black females presented with significantly smaller dimensions than Black males. On the contrary, White males exhibited significantly larger protrusion values than White females. The results of this study corroborate with the literature that sex, population, and modality significantly influence the position of the eye in the orbit, which emphasizes the necessity of creating population- and sex-specific facial approximations guidelines for the placement of the eye in the orbit.