We demonstrate how the Bayesian framework for forensic interpretation can be adapted for casework involving postmortem intervals (PMI) utilizing taphonomic data as well as how to overcome some of the limitations of current approaches for estimating and communicating uncertainty. A model is implemented for indoor cases based on partial body scores from three different anatomical regions as correlated functions of accumulated temperature (AT). The multivariate model enables estimation of PMI for human remains also when one or two local body scores are missing or undetermined, e.g. as a result of burns, scars or covered body parts. The model was trained using the expectation maximization algorithm, enabling us to account for uncertainty of PMI and/or ambient temperature in the training data. Alternative approaches reporting the results are presented, including the likelihood curve, likelihood ratios for competing hypotheses and posterior probability distributions and credibility intervals for PMI. The applicability or the approaches in different forensic scenarios is discussed.
Due to the different types and quality of forensic evidence materials, their DNA content can vary substantially, and particularly low quantities can impact the results in an identification analysis. In this study, the quantity of mitochondrial and nuclear DNA was determined in a variety of materials using a previously described real-time PCR method. DNA quantification in the roots and distal sections of plucked and shed head hairs revealed large variations in DNA content particularly between the root and the shaft of plucked hairs. Also large intra- and inter-individual variations were found among hairs. In additions DNA content was estimated in samples collected from fingerprints and accessories. The quantification of DNA on various items also displayed large variations, with some materials containing large amounts of nuclear DNA while no detectable nuclear DNA and only limited amounts of mitochondrial DNA were seen in others. Using this sensitive real-time PCR quantification assay, a better understanding was obtained regarding DNA content and variation in commonly analysed forensic evidence materials and this may guide the forensic scientist as to the best molecular biology approach for analysing various forensic evidence materials.
This study's objective is to obtain accuracy and precision in estimating the postmortem interval (PMI) for decomposing human remains discovered in indoor settings. Data were collected prospectively from 140 forensic cases with a known date of death, scored according to the Total Body Score (TBS) scale at the post-mortem examination. In our model setting, it is estimated that, in cases with or without the presence of blowfly larvae, approximately 45% or 66% respectively, of the variance in TBS can be derived from Accumulated Degree-Days (ADD). The precision in estimating ADD/PMI from TBS is, in our setting, moderate to low. However, dividing the cases into defined subgroups suggests the possibility to increase the precision of the model. Our findings also suggest a significant seasonal difference with concomitant influence on TBS in the complete data set, possibly initiated by the presence of insect activity mainly during summer. PMI may be underestimated in cases with presence of desiccation. Likewise, there is a need for evaluating the effect of insect activity, to avoid overestimating the PMI. Our data sample indicates that the scoring method might need to be slightly modified to better reflect indoor decomposition, especially in cases with insect infestations or/and extensive desiccation. When applying TBS in an indoor setting, the model requires distinct inclusion criteria and a defined population.
Forensic DNA analysis is routinely performed using polymorphic short tandem repeat (STR) markers. However, for degraded or minute DNA samples, analysis of autosomal single nucleotide polymorphisms (SNPs) in short fragments might be more successful. Furthermore, sequencing of mitochondrial DNA (mtDNA) is often performed on highly degraded or scarce samples due to the high copy number of mtDNA in each cell. Due to the increasing number of complete mtDNA genome sequences available, the limited discrimination power of an mtDNA analysis, may be increased by analysis of coding region polymorphisms in addition to the non-coding variation. Since sequence analysis of the coding region would require more material than generally present in forensic samples, an alternative SNP analysis approach is required. We have developed a one-colour microarray-based SNP detection system for limited forensic materials. The method is based on minisequencing in solution prior to hybridisation to universal tag-arrays. In a first outline of a forensic chip, a combination of 12 nuclear and 21 mitochondrial SNP markers are analysed simultaneously. The mitochondrial markers on the chip are polymorphisms within the hypervariable region as well as in the coding region. Even though the number of markers in the current system is limited, it can easily be extended to yield a greater power of discrimination. When fully developed, microarray analysis provides a promising system for efficient sensitive SNP analysis of forensic samples in the future.
BACKGROUND: To predict mortality risk in victims of violent crimes based on individual injury diagnoses and other information available in health care registries.
METHODS: Data from the Swedish hospital discharge registry and the cause of death registry were combined to identify 15,000 hospitalisations or prehospital deaths related to violent crimes. The ability of patient characteristics, injury type and severity, and cause of injury to predict death was modelled using conventional, Lasso, or Bayesian logistic regression in a development dataset and evaluated in a validation dataset.
RESULTS: Of 14,470 injury events severe enough to cause death or hospitalization 3.7% (556) died before hospital admission and 0.5% (71) during the hospital stay. The majority (76%) of hospital survivors had minor injury severity and most (67%) were discharged from hospital within 1day. A multivariable model with age, sex, the ICD-10 based injury severity score (ICISS), cause of injury, and major injury region provided predictions with very good discrimination (C-index=0.99) and calibration. Adding information on major injury interactions further improved model performance. Modeling individual injury diagnoses did not improve predictions over the combined ICISS score.
CONCLUSIONS: Mortality risk after violent crimes can be accurately estimated using administrative data. The use of Bayesian regression models provides meaningful risk assessment with more straightforward interpretation of uncertainty of the prediction, potentially also on the individual level. This can aid estimation of incidence trends over time and comparisons of outcome of violent crimes for injury surveillance and in forensic medicine.
Introduction: 3-methoxyphencyclidine (3-MeO-PCP) appeared on the illicit drug market in 2011 and is an analogue of phencyclidine, which exhibits anesthetic, analgesic and hallucinogenic properties. In this paper, we report data from a non-fatal intoxication and seven deaths involving 3-MeO-PCP in Sweden during the period March 2014 until June 2016. Case descriptions: The non-fatal intoxication case, a 19-year-old male with drug problems and a medical history of depression, was found awake but tachycardic, hypertensive, tachypnoeic and catatonic at home. After being hospitalized, his condition worsened as he developed a fever and lactic acidosis concomitant with psychomotor agitation and hallucinations. After 22 h of intensive care, the patient had made a complete recovery. During his hospitalization, a total of four blood samples were collected at different time points. The seven autopsy cases, six males and one female, were all in their twenties to thirties with psychiatric problems and/or an ongoing drug abuse. Methods: 3-MeO-PCP was identified with liquid chromatography (LC)/time-of-flight technology and quantified using LC-tandem mass spectrometry. Results: In the clinical case, the concentration of 3-MeO-PCP was 0.14 mu g/g at admission, 0.08 mu g/g 2.5 h after admission, 0.06 mu g/g 5 h after admission and 0.04 mu g/g 17 h after admission. The half-life of 3-MeO-PCP was estimated to 11 h. In the autopsy cases, femoral blood concentrations ranged from 0.05 mu g/g to 0.38 mu g/g. 3-MeO-PCP was the sole finding in the case with the highest concentration and the cause of death was established as intoxication with 3-MeO-PCP. In the remaining six autopsy cases, other medications and drugs of abuse were present as well. Conclusion: Despite being scheduled in January 2015, 3-MeO-PCP continues to be abused in Sweden. Exposure to 3-MeO-PCP may cause severe adverse events and even death, especially if the user does not receive life-supporting treatment.
Measurement of breath alcohol concentration is strongly influenced by timing and the breathing pattern. In particular, shallow expiration and hyperventilation leads to underestimation of the breath alcohol concentration. In the present study, expirograms of alcohol, water and carbon dioxide were recorded in 30 healthy individuals at various breathing manoeuvres (tidal volume, slow maximum and vital capacity expiration, breath holding, and hyperventilation). Estimation of the end expiratory alcohol concentration with the use of simultaneously measured carbon dioxide was shown to reverse the tendency of underestimation at shallow expiration and hyperventilation. These findings indicate that breath alcohol estimations can be performed at shorter expiration time and reduced expired volume compared to existing alcolocks. This is believed to improve their usability and to prevent a possible route for manipulation.
Several case reports and survey studies have indicated that abuse of anabolic androgenic steroids (AAS) often leads to increased aggressiveness and feelings of hostility that may occasionally trigger violent behaviour. Other observations indicate that many users of AAS also abuse alcohol and/or various illegal substances. Since substance abuse is a well-known risk factor for violent behaviour, it could be that violence committed by AAS users might, at least in many cases, actually be caused by abuse of other drugs. In order to examine this possibility further here, the criminal histories (in terms of incidences of convictions) of deceased users of AAS with (AASpos-subst.pos) and without (AASpos-subst.neg) signs of abuse of other illegal substances were compared to the corresponding histories of deceased users of illicit substances testing negatively for AAS (subst.pos-AASneg) at the time of autopsy. The risk of being convicted for a crime against property was significantly higher in the subst.pos-AASneg group than in either the AASpos-subst.neg or AASpos-subst.pos groups (RR=0.048 versus 0.408). At the same time, the risk of being convicted for a crime of violence was at least as high for the two AAS-positive groups as for the AAS-negative group. Furthermore, when compared with the first 3 years after the first criminal conviction, a pronounced increase in the proportion of incidence of violent crimes and a marked reduction in the proportion of incidence of crime against property was observed during the 3-year period immediately preceding death only among the AASpos-subst.neg subjects. In conclusion, the incidence of violent crime among users of AAS without signs of other drug abuse was comparable to the corresponding incidences for drug addicts without AAS use. This observation suggests that the violent criminality observed among AAS users is not confounded in any systematic fashion by abuse of other drugs. The findings also indicate that use of AAS in certain predisposed individuals might cause a high rate of violent crimes, especially if the use of AAS is combined with the use of other illegal substances.
Abusive Head Trauma (AHT) is considered by some authors to be a leading cause of traumatic death in children less than two years of age and skull fractures are commonly seen in cases of suspected AHT. Today, diagnosing whether the observed fractures are caused by abuse or accidental fall is still a challenge within both the medical and the legal communities and the central question is a biomechanical question: can the described history explain the observed fractures? Finite element (FE) analysis has been shown a valuable tool for biomechanical analysis accounting for detailed head geometry, advanced material modelling, and case-specific factors (e.g. head impact location, impact surface properties). Here, we reconstructed two well-documented suspected abuse cases (a 3- and a 4-month-old) using subject-specific FE head models. The models incorporate the anatomical details and age-dependent anisotropic material properties of infant cranial bones that reflect the grainy fibres radiating from ossification centres. The impact locations are determined by combining multimodality images. The results show that the skull fracture patterns in both cases of suspected abuse could be explained by the described accidental fall history, demonstrating the inherent potential of FE analysis for providing biomechanical evidence to aid forensic investigations. Increased knowledge of injury mechanisms in children may have enormous medico-legal implications world-wide.
Treatment of morphine, at room temperature, with a mixture of trifluoroacetic anhydride (TFAA) and acetic acid (20-30min) affords good yields of heroin. GC-MS and HPLC examination shows that heroin produced by this route to be extremely clean, but the product contains slightly less heroin than observed via the more traditional acetic anhydride (AA) route (76.1% versus 83.55%); and greater quantities of 3-MAM and 6-MAM (6.9% versus 0.75% and 7.13% versus 0.63%). The concentration ratios of the major alkaloid impurities were found to be both production method (TFAA and AA) as well as morphine extraction methodology dependant. Data contained herein describe the impact of this new production method on current intelligence efforts, largely by-passing existing heroin signature programs and the UNDCP's efforts to restrict access to key synthetic precursors. Given the methodology dependency we find that examination of the major alkaloid ratios is unsuitable for the development of a new heroin signature program. Further examination of the TFAA methodology allowed the identification of TFAA specific marker compounds, namely bis-trifluoroacetylmorphine (30), 3-trifluoroacetyl-6-acetylmorphine (31), 3-acetyl-6-trifluoroacetylmorphine (32) and trifluoroacetylcodeine (33). However, the hydrolytic lability of trifluroacetyl esters requires careful treatment of suspect samples, thus we propose a modification to existing HSP's in instances were the 6-MAM/WM ratio falls within the average minimum and maximum values of 6.17 and 17.32.
Tasmanian opium accounts for 25% of the world's legal supply of opium straw, and in 1998-99 sufficient numbers of flower pods (66,013) to manufacture ca 500 kg of heroin were stolen. Whilst the heroin signature program has been developed to determine the origin of heroin from other key producers, no such signature currently exists for Tasmanian derived heroin. Tasmanian poppies contain a unique alkaloid, oripavine, which is the source of 'marker' impurities in illicit heroin produced from Tasmanian poppy straw. Treatment of oripavine (500mg) under Thiboumery and Mohr heroin processing conditions, followed by simple evaporative workup afforded 613 mg of a dark orange residue, which upon extensive chromatographic purification yielded oripavine 3-acetate (2) 22 mg; 3-acetyl-N-acetyldesthebaine (3) 35 mg; 3-acetyl-6-methoxy-4,5-epoxyphenanthrene (4) 5.8 mg; 3,4-diacetyl-6-methoxyphenanthrene (5) 27 mg; and 3,4,6-methoxy-5-[2(N-methylacetamido)]ethylphenanthrene (6) 52 mg. Compounds (2-6) are derived from oripavine and are unique to heroin derived from the Tasmanian poppy Papaver somniferum N. Analysis of illicit heroin samples seized from Turkey, Pakistan, Columbia and Myanmar did not reveal any of the aforementioned marker compounds. We have, however, identified four of these marker compounds (3-6) in seized heroin samples from Australia suggesting that they are of Tasmanian origin. Complete details of the isolation and identification of these compounds are provided.
The allele frequencies at the tetranucleotide repeat (TCTA) vWA locus in the vWF gene were determined in the general Finnish population, in a population representing an internal isolate of Finland, in the Vologda-Russian population, and in US Black population samples. The allele and genotype frequencies from these population samples were compared with each other and with those reported from Spanish and British population samples. Statistically significant differences were demonstrated between most of the different groups (Finns vs. Vologda-Russians, Finns vs. US Blacks, Finns vs. Spanish, Vologda-Russians vs. US Blacks, Vologda-Russians vs. Spanish, US Blacks vs. Spanish and US Blacks vs. British Caucasians), but not between the two Caucasoid population samples from Finland and Great Britain, nor between or within the subpopulation samples from Finland and those from Vologda-Russia. In addition, the vWA marker was evaluated and demonstrated to be reliable for forensic purposes and paternity testing.
There are previous studies that have found associations between specific injury patterns and different victim-offender relationships (VORs) in homicides. We have used quantitative injury severity scores to further investigate this issue. The amount and severity of injuries were assessed in 178 Swedish homicide victims, retrospectively included from the years 2007-2009. We analyzed whether different injury measures could be used to predict the VOR. In addition to a deeper understanding of violent behavior, such associations may be of help to homicide investigators for offender profiling. The victims' injuries were assessed with eleven different methods. The cases with known VORs were divided into four categories: partner, relative, acquaintance, and stranger. The injury seventies were then compared between these categories. No relevant differences were found. Thus, the current study does not support the claim that the VOR can be predicted from the injury severity in a general homicide population. These findings are in contrast to the results of some previous studies but confirm those of others.
The use of anabolic androgenic steroids (AAS) has been associated with different adverse effects, some of which potentially lethal. Most users of AAS are male, but the prevalence of such use appears to be increasing in females. Here we present a sudden unexpected death in a female fitness athlete with a possible connection to use of doping agents.