Multiple new analogues from the 2-benzyl benzimidazole or "nitazene" class of drugs have emerged on the drug market in recent years. Nitazenes are highly potent μ-opioid receptor agonists that present a substantial public health concern due to their elevated risk of severe toxicity in overdose and their significant potential for misuse. We report on a case involving an overdose with another new analogue from this class, protodesnitazene. The drug has a similar potency to fentanyl and has not been previously reported in toxicology specimens or drug seizures. Protodesnitazene was initially identified by LC-QTOF-HRMS (High Resolution Mass Spectrometry) and distinguished from relevant isomers by chromatographic separation, with spectral and retention time matching against reference standards. A quantitation method employing solid phase extraction using mixed mode cartridges and utilizing LC-MS/MS operating in MRM mode was developed and partially validated for non-routine analyses. Concentrations for the parent drug were determined in a range of postmortem matrices and femoral blood levels (77-222 ng/mL) were found to be comparable to previously identified desnitazene compounds. Protodesnitazene was observed to metabolize extensively by N-dealkylation, O-dealkylation, and hydroxylation. Glucuronides were not present at high levels in the blood but were prominent in the urine. Protodesnitazene was also identified in an associated seized powder.

Smartphone operating systems generate artifacts such as snapshots, state databases, and usage logs to manage application state transitions during app-switching. However, these artifacts differ across operating systems in storage location, format, and retention period, which limits the reproducibility and interpretability of forensic analysis even when the underlying user behavior is identical. Android's Protobuf-serialized records and iOS's KTX-format snapshots further complicate analysis, as their complex structures and limited tool support often necessitate manual processing. This study examines app-switching artifacts on Android and iOS to reconstruct user behavior, focusing on UsageStats, Recent Tasks, and snapshot images on Android, and KnowledgeC.db, applicationState.db, and snapshot artifacts on iOS. We analyze how each platform records temporal information and application state during app-switching, termination, and device reboot, and show that correlation across artifacts enables cross-validation, resolving the resulting inconsistencies. The results reveal discrepancies between UsageStats records and other app-switching artifacts on Android, and missing endDate values and incomplete records during abnormal termination in iOS's KnowledgeC.db. These findings demonstrate that single-artifact analysis can lead to misinterpretation. We further develop an automated tool that parses, aligns, and visualizes multiple artifacts to reconstruct app-transition flows, confirming its practical applicability to mobile forensic analysis.

The exponential expansion of digital evidence across traditional computing systems, mobile devices, cloud infrastructures, and IoT ecosystems presents new issues for forensic investigators. Modern forensic acquisitions frequently produce multi-terabyte datasets with substantial inter-case redundancy, which significantly affects storage capacity, processing time, and investigation costs. Data deduplication is a potential approach; however, its use in forensic contexts is limited by special operational requirements, such as total data integrity, court-admissible audit trails, and resistance to anti-forensic manipulation. This paper provides a comprehensive survey and evaluation of forensic data deduplication methods. We propose a five-dimensional forensic taxonomy that classifies techniques based on granularity, forensic integrity, temporal placement, verification methodology, and scope & scale. Using multi-criteria decision analysis, we create a Deduplication Reliability Index (DRI) to compare existing systems to forensic requirements statistically. We also systematically identify six types of adversarial threats particular to forensic deduplication, such as hash collision exploitation, deduplication oracle attacks, and reference mapping manipulation. Our analysis shows that file-level and fixed-block deduplication have the highest DRI scores (4.35-4.30), indicating that they are optimally suited for forensic adoption, whereas semantic, probabilistic, and lossy techniques score less than 3.0 due to poor verification and integrity assurances. The report concludes by proposing crucial research goals, such as standardized validation frameworks, adversarial-resilient deduplication structures, and efficient zero-knowledge verification algorithms for forensics.

The identification of human remains in mass-casualty incidents requires rapid and reliable forensic DNA analysis, particularly when dealing with degraded skeletal material. Although rapid forensic identification is a fundamental objective in all disaster victim identification (DVI) operations, the repatriation of deceased hostages from the October 7, 2023, attack, c. 2 years postmortem (PM), imposed an additional challenge of a fixed operational deadline dictated by the implementation of the hostages-prisoners exchange agreement. To accelerate STR profiling, we reconfigured the conventional sequential process (extraction, quantification, amplification) into a flexible, decision-driven workflow. The new workflow incorporates a shortened 1.5-h DNA incubation, predefined dual-volume PCR amplification, and deferred DNA quantification. Built-in contingency mechanisms including multi-sample per case and enhanced 33-Cycle PCR-enabled immediate progression to alternative pathways when required. The accelerated workflow was applied in a real-world operational setting involving 37 cases (79 samples) collected during multiple repatriation phases. Informative STR profiles were obtained from 90% (71/79) of samples within 4 h per repatriation phase. Although eight individual samples remained non-informative, the integrated contingency mechanisms enabled successful resolution of all 37 cases (100%). Informative profiles were generated across a broad range of DNA quantities, including low-template samples, and from diverse skeletal elements. By comparison, the RapidHIT™ system generated an informative profile in only one of 21 samples. These findings demonstrate that restructuring the DNA workflow into a flexible, decision-driven process with built-in contingency mechanisms enables rapid and reliable profiling. The proposed workflow provides a practical operational framework for time-critical forensic DNA identification.

Brain lesions are known to affect cognition, emotions, and behavior, and have been implicated in cases of violence, particularly when involving neural circuits responsible for impulse control, emotional regulation, and judgment. While tumors, traumatic brain injuries, vascular abnormalities, and other types of brain lesions have been associated with psychiatric and behavioral disturbances, cerebral arteriovenous malformations (AVMs) have rarely been linked to psychosis and not with homicidal violence. We present the case of a 14-year-old boy with a large inoperable left parieto-occipital arteriovenous malformation extending into the temporal lobe who developed progressive neuropsychiatric symptoms culminating in psychosis and an explosive and fatal knife attack on neighbors. His developmental course was remarkable for early speech delay, attention deficit hyperactivity disorder (ADHD), oppositional behaviors, emotional dysregulation, severe headaches, and eventual psychotic decompensation characterized by paranoid delusions, disorganized thinking, and behavioral disinhibition. Prior to the homicidal event, neuroimaging showed progression of his AVM with cerebral edema, and John developed a Psychotic Disorder due to a Medical Condition (AVM). After arrest, he was found incompetent to stand trial and eventually placed in a state psychiatric facility. In contrast, his twin brother, raised in the same environment, was developmentally typical and psychiatrically healthy. How brain lesions can contribute to violent acts is a complex topic given the multifactorial origins of aggression. This case report, using a developmental approach, illustrates the connection between focal brain pathology, a cerebral AVM, and homicidal violence in a teenage boy. Treatment approaches, rehabilitation efforts, and legal implications are considered.

Polymer receivers fabricated by fused filament fabrication (FFF) are increasingly encountered in forensic casework; however, their firing-cycle behavior and the stability of associated ballistic toolmarks remain poorly understood. In this study, Ruger 10/22-pattern FFF-printed receivers produced from polylactic acid (PLA) were evaluated under controlled indoor shooting range conditions alongside a factory-produced aluminum receiver using identical trigger, bolt, and barrel components. Fired cartridge-case first-impact coordinates were recorded in three dimensions to quantify ejection dispersion and to estimate relative bolt kinetic energy, using the mean ejection distance as a conservative proxy. Under the improvised barrel-retention configuration used in this study, the FFF-printed receivers produced shorter and more variable fired cartridge-case ejection ranges than the factory reference, corresponding to approximately 46%-57% of the factory receiver's relative bolt kinetic energy, depending on ammunition type and reference condition. This observation was consistent with greater sensitivity to assembly-dependent factors, including headspace-related variation and barrel retention instability, and with reduced bolt acceleration. To examine systematic changes in toolmark stability under conditions of reduced barrel-to-receiver rigidity relevant to improvised privately manufactured firearm (PMF) assembly practices documented in forensic submissions, an unsecured-barrel configuration was used. Under this configuration, sequential firing produced progressive changes in ballistic toolmark expression: chamber-contact regions diminished and shifted over short firing sequences, and firing-pin impression footprints were consistently smaller and less distinct than those produced by the factory reference receiver. These findings provide practical insights for the forensic interpretation of fired cartridge-case toolmark patterns, operability assessment, and evaluation of toolmark reliability in PMFs.

Volatile organic compounds associated with explosives such as Composition C-4 serve as important targets for canine training as well as field analysis. In parallel, 1-bromooctane (1-BO) is a benchmark to contextualize canine performance and aid interpretation of results. Improved understanding of the collection and recovery of these odorants is important for optimizing canine training aids, interpreting canine responses, and better understanding factors that may contribute to nuisance alerts. This study highlights the first known evaluation of the SNT SKR 2000, a scent transfer unit for non-contact sampling of VOCs associated with C-4. The STU unit, along with headspace- solid phase microextraction (HS-SPME) and gas chromatography- mass spectrometry (GC-MS), was evaluated to collect 2,3-dimethyl-2,3-dinitrobutane (DMNB), cyclohexanone, and 2-ethyl-1-hexanol from C-4. Additionally, 1-BO was sampled under identical conditions to provide a simple, non-energetic reference. The sampling parameters comprising of flow rate and sampling time were optimized and it was observed that a low flow rate coupled with a sampling time of 3 min yielded highest recovery of all three VOCS. The STU unit demonstrated reliable detection of VOCs from as little as 664 mg of C-4. 1-BO produced strong, reproducible signals that served as a practical check on sampling consistency. Compound-specific behavior, along with sorption affinity to the sterile gauze pad as well as the SPME fiber, were the key factors responsible for the recovery of the analytes of interest. The STU unit was successful in recovering VOCs from both porous surfaces such as cardboard and non-porous surfaces such as metal paint cans, with higher DMNB retention observed on porous substrates. 1-BO was also recovered from both configurations, illustrating capture from a single-odor environment.

The forensic identification of "overkill" homicide remains challenging due to the absence of a standardized, evidence-based definition. This study aimed to address this gap by establishing a quantitative criterion and delineating the criminological profile of overkill in the Tunisian context. A retrospective study of autopsy records collected over a 34-year period in the forensic department of the University Hospital of Monastir in Tunisia. During the study period, all the autopsied homicide cases were examined and analyzed using the autopsy reports as well as medical records and court reports. A multidisciplinary operational definition was applied. Statistical analysis included multivariate logistic regression and ROC curve analysis to identify predictive factors and determine diagnostic thresholds. Of the 297 homicides, 83 (27.9%) were classified as overkill based on a multidisciplinary operational definition integrating quantitative and qualitative indicators of excessive violence. Overkill cases were characterized by a significant overrepresentation of female victims (36.1% vs. 12.1%, p < 0.001), intimate relationships (21.7% vs. 7.9%, p = 0.002), and perpetrators acting alone with higher rates of criminal and psychiatric history. The number of fatal injuries was the sole independent predictor (OR = 16.3, p < 0.001). A threshold of ≥ 2 fatal injuries provided optimal discrimination (AUC = 0.982, sensitivity 97.6%, specificity 98.1%). This study provides an attempt to identify overkill, establishing ≥ 2 fatal injuries as a diagnostic threshold. The findings characterize overkill as distinct form of expressive violence. Despite the promising nature of our results, it is imperative that these findings be interpreted with caution and ideally correlated with other objective criteria.

Recording friction ridge patterns is a critical step in personal identification, as only clear impressions can be reliably compared with database records. This study presents two approaches-image processing and a fiber-optic-inspired total internal reflection method (FOM)-and compares them with frustrated total internal reflection (FTIR), ink, and powder methods to identify a simple and reliable workflow for forensic evidence collection. The results indicate that no single method is suitable for all fingerprint conditions; instead, a combination of complementary techniques is required. The recommended workflow begins with photographic documentation of the native friction ridge appearance for subsequent image processing. In practice, fingerprint recording is primarily performed using the FOM, supplemented by powder when necessary. The FOM provides a simple and practical approach for visualizing ridge detail using minimal equipment and shows reduced interference from wrinkles, allowing more continuous ridge structures to be observed. However, its performance is reduced in hyperkeratotic fingerprints, which can be improved by combining the method with powder. Image processing also demonstrates considerable potential, and in some cases, processed images are comparable to those obtained using contact-based methods. When contact-based techniques fail to reveal ridge detail, image processing may still provide sufficient information for identification.

Burn injuries are common in childhood and may occur in accidental or non-accidental circumstances, making forensic interpretation challenging. Evaluation is difficult when clinical findings, reported history, and contextual evidence are incomplete or discordant. We present three pediatric cases evaluated through a structured forensic approach integrating clinical findings, lesion morphology, reported circumstances, developmental assessment, scene reconstruction, and experimental testing. The first involved a 7-year-old girl with scald burns of the buttocks and right lower limb following the reported rupture of a bag filled with boiling water; analysis supported an accidental mechanism. The second concerned a 9-month-old boy with deep partial-thickness burns of the left hand reportedly caused by accidental contact with a stove hot plate; lesion analysis, scene reconstruction, thermal testing, and developmental assessment were inconsistent with the reported history and supported abuse. The third involved a 13-year-old girl with multiple rounded burn-like skin lesions in different stages of healing; extensive clinical investigations did not identify a specific dermatologic or systemic cause, while toxicological analysis of lesional skin supported exposure to an aluminum-containing topical product, namely her deodorant. Multidisciplinary assessment indicated a deliberate mechanism, with self-infliction considered the most probable interpretation. These cases show that no single feature is diagnostically decisive in the forensic assessment of pediatric burns. Determination of injury mechanism and intentionality requires multidisciplinary integration of lesion morphology, developmental plausibility, thermal dynamics, toxicological findings, and scene reconstruction. In this case series, this structured approach supported three distinct mechanisms: accidental scald injury, inflicted contact burn, and deliberate self-inflicted burn-like injury.

Examination of the fetal brain represents a crucial step in the diagnostic assessment of fetal death in utero, particularly in cases of unexplained intrauterine fetal death (IUFD). Prolonged intrauterine retention, advanced autolysis, and the intrinsic structural immaturity of the fetal brain frequently compromise tissue integrity, limiting diagnostic evaluability. We describe a brain extraction technique preserving the dura mater combined with a modified alcohol-formalin-acetic acid fixation protocol aimed at improving morphological preservation and diagnostic yield. Between 2017 and 2019, 295 fetal autopsies were performed at the regional reference center for SIUD-IRCCS Istituto Giannina Gaslini, Genoa, Italy. The method enables en bloc removal of the brain completely enveloped by the intact dura mater, which acts as a protective scaffold during handling and fixation. The brain is suspended in a modified Culling solution (40% buffered formalin at 10%, 40% ethanol at 95%, 20% glacial acetic acid) for approximately 20 days prior to serial sectioning according to the Charcot's technique. This approach appears to reduce mechanical disruption even in severely macerated cases, ensures uniform tissue compaction, shortens fixation times compared with formalin alone, and preserves cortical, ventricular, and brainstem anatomical relationships. It also allows gross exclusion of major abnormalities, including extensive intraventricular and intraparenchymal hemorrhages, and enables systematic inspection and sampling of the dural venous sinuses. Histological and immunohistochemical analyses demonstrated satisfactory preservation quality comparable to conventional methods. This simple and reproducible technique enhances evaluability in fetal autopsies and supports more reliable etiological assessment in cases of IUFD.

Forensic entomology currently represents one of the best approaches for estimating the minimum postmortem interval (PMIMIN) in medicolegal death investigations given certain parameters and assumptions are met. However, validation of standard estimation methods used in this field are few and far between. Our project aimed to quantify errors associated with four aspects of a typical insect age estimation: insect species, development stage, base temperature for calculating accumulated degree hours, and reference dataset. To do this, we collected 725 larval dipteran samples from 79 human donors at the Anthropology Research Facility (ARF) at the University of Tennessee, Knoxville, TN, USA. Standard age estimations were performed with all blow fly larvae to estimate the time of placement of donors and assess accuracy depending on species and larval stage used, base temperature selection, and reference dataset selection. Base temperature selection did not significantly impact estimation accuracy for most (i.e., six out of seven) blow fly species (p > 0.05). However, there was a significant impact of development stage (p < 0.001), reference dataset selected (p < 0.001), and blow fly species used (p < 0.001) on estimation accuracy. Our results underscore the importance of method validation and demonstrate that not all components used for age estimations are equally informative. This dataset currently represents the largest effort to validate blow fly estimation methods using human remains, and one of the only efforts made in forensic entomology to validate developmental datasets to date.

Synthetically derived tetrahydrocannabinol (THC) products, including vaping liquids and edibles, are widely available in the US. Serious adverse events associated with the use of THC products are reported in large-scale studies for both adults and children and include intoxication, psychosis, encephalopathy, CNS depression, respiratory failure, and acute cardiovascular emergencies. Between 2019 and 2024, a variety of synthetically derived "Δ[9]-THC" and "Δ[8]-THC" products were submitted for quantitative THC analysis. The products contained various combinations of seven positional THC isomers: Δ[9]-tetrahydrocannabinol (Δ[9]-THC), Δ[8]-tetrahydrocannabinol (Δ[8]-THC), Δ[6a10a]-tetrahydrocannabinol (Δ[6a10a]-THC), Δ[10]-tetrahydrocannabinol (Δ[10]-THC), Δ[4(8)]-iso-tetrahydrocannabinol (Δ[4(8)]-iso-THC), Δ[8]-iso-tetrahydrocannabinol (Δ[8]-iso-THC), and exo-tetrahydrocannabinol (exo-THC). Several products contained THC isomers in combination with tetrahydrocannabiphorols (THCPs) or hexahydrocannabinols (HHCs). A series of quantitative high-performance liquid chromatography-ultraviolet detection (HPLC-UV) methods for THCs, THCPs, and HHCs was developed and validated. The methods use ACE Excel mixed C18-aromatic 3.0-micron or Cosmocore/Cosmosil cholesterol-ligand-based 2.6/2.5-micron columns. Optimized resolution for the THC isomers was obtained using ternary mobile phases containing methanol, acetonitrile, and acetic acid buffer and a 45°C column temperature. Representative data for synthetically derived cannabinoid products analyzed over a five-year period are provided. Total THC isomer contents for vaping liquids and dabs ranged from 25 to 96% w/w. Total THC isomer contents for gummies and other candies ranged from 57-321 mg/gummy or 13-24 mg/candy piece, respectively. The highest amount of cannabinoids was found in a THC/HHC combination product with a Δ[8]-THC content of 649 mg/gummy and a total combined THC/HHC isomers content of 791 mg/gummy.

Examining perpetrator characteristics of, and risk factors for, different types of mass murder, such as family mass murder-the most common type-could have important ramifications for preventive efforts. Histories of domestic violence and mental illness are of particular interest. We examined 944 cases of mass murder from the Columbia Mass Murder Database that occurred in the United States between 1970 and 2019, identifying 377 incidents (39.9%) in which at least one victim was a family member of the perpetrator. We collected information on histories of domestic violence and characteristics of mental illness among perpetrators from media reports and court and police records. Overall, 202 (21.4%) cases included histories of domestic violence. Firearms were used in four-fifths (759/944; 80.4%) of all cases of mass murder, while family mass murder was significantly less likely than other mass murder events to involve firearms (74.8% vs. 84.1%, χ[2] 12.5, p < 0.001). Perpetrators of family mass murder were significantly more likely to take their own lives at the time of the event than were other personal-cause mass-murder perpetrators (43.8% vs. 16.8%, χ[2] 82.8, p < 0.001). These data extend findings on differences between family mass murder and other types of mass murder when the three-victim definition is used. This study further supports previous reports of the limited contribution of both psychotic and non-psychotic mental health conditions to all types of mass murder, including family mass murder, and that policies focused elsewhere may be more effective at stemming the tide of all types of mass murder, including family mass murder.

Forensic entomology, and potentially microbiology in the future, can be used during death investigations to corroborate an estimated time since death. Instances where products are introduced to a cadaver, either in attempt to conceal or by accident, can affect decomposition and succession of associated decomposer taxa (i.e., insects and bacteria). In this study, we tested the effect of two bleach (sodium hypochlorite) submersions on the outdoor decomposition and succession of carcass, soil, and beetle postmortem microbiomes using replicate (n = 5 per treatment) stillborn swine carcasses. Microbiomes from beetles, the carcasses, and the soil beneath them were sequenced from samples collected every two days. Beetle communities collected from pitfall traps were not significantly different between bleached and control carcasses through decomposition; however, there were fewer beetles collected from bleached carcasses until the last experimental day. Results from 16S rRNA amplicon sequencing revealed that microbiomes of carcasses and the soil beneath them did not significantly change when carcasses were bleached, and beetle internal microbiomes were not affected by the addition of bleach. Random forest modeling using soil microbiomes from underneath carcasses from both treatments was used to predict time since placement in the field with a 74.4% successful prediction rate, and modeling using beetle internal microbiomes predicted beetle family with 74.0% success. The introduction of bleach to the carcasses did not affect microbial or beetle communities, total decomposition time, or decrease accuracy of time of placement models.