Of earprints, fingerprints, scent dogs, cot deaths and cognitive contamination--a brief look at the present state of play in the forensic arena

Over the last decades, the importance of technical and scientific evidence for the criminal justice system has been steadily increasing. Unfortunately, the weight of forensic evidence is not always easy for the trier of fact to assess, as appears from a brief discussion of some recent cases in which the weight of expert evidence was either grossly over- or understated. Also, in recent years, questions surrounding the value of forensic evidence have played a major role in the appeal and revision stages of a number of highly publicized criminal cases in several countries, including the UK and the Netherlands. Some of the present confusion is caused by the different ways in which conclusions are formulated by experts working within the traditional approach to forensic identification, as exemplified by (1) dactyloscopy and (2) the other traditional forensic identification disciplines like handwriting analysis, firearms analysis and fibre analysis, as opposed to those working within the modern scientific approach used in forensic DNA analysis. Though most clearly expressed in the way conclusions are formulated within the diverse fields, these differences essentially reflect the scientific paradigms underlying the various identification disciplines. The types of conclusions typically formulated by practitioners of the traditional identification disciplines are seen to be directly related to the two major principles underpinning traditional identification science, i.e. the uniqueness assumption and the individualization principle. The latter of these is shown to be particularly problematic, especially when carried to its extreme, as embodied in the positivity doctrine, which is almost universally embraced by the dactyloscopy profession and allows categorical identification only. Apart from issues arising out of the interpretation of otherwise valid expert evidence there is growing concern over the validity and reliability of the expert evidence submitted to courts. While in various countries including the USA, Canada and the Netherlands criteria have been introduced which may be used as a form of input or output control on expert evidence, in England and Wales expert evidence is much less likely to be subject to forms of admissibility or reliability testing. Finally, a number of measures are proposed which may go some way to address some of the present concerns over the evaluation of technical and scientific evidence.     

Blood alcohol concentrations of sudden unexpected deaths and non natural deaths.

This study reports on the relationships between the blood alcohol concentration (BAC) and the cause of death - which is of course common knowledge for forensic scientists! Our special aim was to gain unselected data for generalizing conclusions. The blood of 2465 consecutive cases (86% of all 2852 sudden unexpected and unnatural fatalities investigated at the Institute for Legal Medicine in Hamburg during the year 1989) was analysed. The BAC was evaluated according to sex, age, cause of death and place of death. In natural causes of death there were 80% cases under 0.05% BAC. Endocrine and digestive system diseases in particular were associated with positive BAC values. In unnatural death cases the BAC under 0.05% was found in 64% of the suicides, 62% of the accidents, 54% of the homicides and 51% of the drug intoxications. The drowning cases showed higher BAC's than traffic accidents. In suicides middle aged males had high BAC's.     

Blood alcohol in sudden and unexpected deaths

Blood alcohol concentration was determined in 1672 sudden and unexpected natural and non-natural out-of-hospital deaths. The material covered all medicolegal autopsies in the province of Uusimaa which has a population of approximately 1.1 million inhabitants. In general, the prevalence of cases with alcohol in the blood at the time of death was high but varied considerably according to sex, age, and the cause and manner of death. The blood alcohol result was positive in 36% of the male and in 15% of the female material. In 59% of the alcohol-positive male and in 54% of the alcohol-positive female cases the actual concentrations were at least 1.5%. Acute use of alcohol was regarded as a significant condition contributing to death in 23% of the whole male and in 8% of the whole female material. These gross results and the details presented indicate that the acute use of excess alcohol is a factor contributing to non-natural but also to sudden and unexpected natural deaths to an extent that is not generally known. The results also emphasize that simple blood alcohol determination should be a routine procedure in the autopsy praxis of all sudden and unexpected natural and non-natural out-of-hospital deaths.     

Malaria deaths in the United States: case report and review of deaths, 1979-1998

Malaria is the world's most important parasitic disease, accounting for an estimated 300 to 500 million new cases and between 1.5 and 2.7 deaths annually. The majority of these deaths occur in sub-Saharan Africa where malaria is endemic and are the result of infection with Plasmodium falciparum. The number of deaths in the United States due to malaria is comparably much lower and involves so-called "imported" cases in which U.S. travelers acquire the infection upon travel to endemic areas and subsequently return to the United States or in which infected foreign citizens travel to the United States. There were a total of 118 deaths due to malaria in the United States between 1979 and 1998 with an average of 5.9 deaths per year. Specific epidemiological data provided by the CDC regarding the 40 deaths that occurred between 1992 and 1998 yielded the following results. Deaths occurred in patients ranging from 9 months to 89 years of age (median, 53 years). Thirty-eight (95%) of these were due to P. falciparum and two (5%) due to P. vivax. Anti-malarial chemoprophylaxis was taken in 40% of cases, not taken in 45% of cases, and unknown in 15% of cases. Twenty-four (60%) of the cases involved U.S. travelers to endemic areas, of whom 59% traveled to Africa, 25% to South America, 8% to India, 4% to Haiti, and 4% to unspecified areas. The remaining cases included eleven foreign travelers to the U.S. (27.5%), three induced cases (7.5%), and two undetermined cases (5%). Thirty-nine (98%) of the cases were diagnosed antemortem and only one case was known to have come to the attention of the medical examiner/coroner. An illustrative case report demonstrates many of the features associated with fatal malaria infections in the United States. The case involves a U.S. student who was studying in Africa and who, by report, had not taken antimalarial chemoprophylaxis. Despite seeking medical attention, the patient was not diagnosed with P. falciparum infection and cerebral malaria until the time of medico-legal autopsy, where the classic gross and microscopic features of cerebral malaria were identified. This case represents one of the few cases of P. falciparum infection in the United States not diagnosed antemortem. Given the worldwide prevalence of the disease, increasing international travel, and rapidly developing drug resistance, malaria will continue to be an important disease and should be considered in cases of sudden, unexplained deaths. By reviewing the major epidemiological features of malaria-related deaths in the United States and by presenting the major gross and microscopic features of cerebral malaria, an attempt is made at raising the awareness of the forensic community to the potential of malaria-related deaths.     

Characterization of lesions in hanging deaths

Hanging is a common method of committing suicide and a routine task in medico-legal autopsies. The hanging mark is the most relevant external sign and its characteristics are well known, but, for unknown reasons, there are major differences in reports on internal findings. We retrospectively studied 228 consecutive cases of hanging deaths. A complete standard autopsy was performed for every case. We investigated the association between the characteristics of the hanging mark and the frequency of bone, cartilage, soft tissue, and vascular injuries with the mode of suspension. Most cases (75.3%) presented some kind of bone or cartilage fracture, but these were unrelated to any of the variables studied. Vascular lesions are clearly more infrequent: intimal injuries were found in the carotid artery (9.1%), the jugular vein (2.2%), and ruptures of the carotid adventitial layer (21.7%). These could be partially associated with the use of a hard fixed noose and body weight.     

Importance of storing emergency serum samples for uncovering murder with insulin

Using the polymerase chain reaction (PCR), we studied the short tandem repeat (STR) polymorphism observed at the D12S391 locus. In 350 Japanese examined, 14 different alleles ranging from 209 bp to 261 bp were detected. Allele 18 (221 bp) showed the highest frequency at 0.30. Observed and expected values of respective genotypes satisfied the Hardy-Weinberg equilibrium (chi 2 = 24.08, P = 0.24, df = 20). In addition, 18 additional sequence structures (suballeles), were detected in this study. Within the suballeles, sequence variants, in which the initial repeat of (AGAT) was replaced with (AGGT), was found in five samples. It was found that the analysis of single-strand conformation polymorphism (SSCP) before sequence analysis was useful for distinguishing these suballeles.     

Explosion-related deaths in Sweden--a forensic-pathologic and criminalistic study

All cases of death caused by explosions of explosive solids, fluids and gases in Sweden during the 6-year period 1979-1984 were analyzed. Among the total of 61 fatalities 33 (54%) were due to accidents (2/3 of them occupational and 1/3 miscellaneous accidents), 25 (41%) were suicides, and only 3 (5%) were associated with terrorist activity. About one half of the occupational accidents were caused by deficient safety devices or defective equipment, while the other half was due to transgression of regulations. All suicides were males, relatively elderly, the majority of them burdened with somatic and mental diseases, alcoholism, social or economical problems, most of them being familiar with explosives. The anatomical localization of suicidal explosive injuries was regular and symmetric, while the accidental and terrorist injuries showed great variations. The terrorist-associated deaths had common features different from all other death cases, strongly suggesting the same type of bomb and the same terrorist group. Explosives caused only superficial burns or singes. Symmetric hemorrhages of the vocal folds and fracture of the laryngeal skeleton were found, as well as ruptures of trachea and lungs. When not ruptured, the lungs showed to different types of injury: hyperinflation, probably due to the blast-induced barotrauma to the respiratory passages, or lung contusions. In cases of suspected terrorist explosions close collaboration between the forensic pathologists and police investigators is mandatory since the bodies of victims protect parts of the bomb from fire or from being spread over a larger area and thus constitute a part of the crime scene.     

家兔低压电击伤后血清LDH和HBDH活性变化

目的研究家兔非热低压电击伤后不同时间乳酸脱氢酶（lactate dehydrogenase,LDH）和羟丁酸脱氢酶（hydroxybutyrate dehydrogenase,HBDH）活性的变化．为I临床和法医学非热电击伤提供诊断依据。方法健康新西兰大白兔40只,随机分为对照组和电击伤后7个时间点的实验组,每组5只。实验组使用本室已建立的非热低压电击伤方法处理,电击后各实验组动物按照预定时间点麻醉后抽取5mL心室血．测定血清LDH,HBDH酶活性。结果在非热低压电击伤后家兔目标血清酶活性发生了动态变化,有一定规律性,其中LDH活性在电击伤后4、12h和1、2、3d明显升高（4、12h和1d P〈0．01;2和3d P〈0．05）;HBDH活性在电击伤后2和3d明显升高（P〈0．05）;电击组HBD肌DH比值在2、4和12h与对照组比较显著降低（P〈0．01）。结论动态监测LDH、HBDH活性,可为非热电击损伤的诊断,损伤时间推断提供理论依据。     

Trends and pattern of drug abuse deaths in Maryland teenagers

The Office of the Chief Medical Examiner of Maryland recorded a total of 149 drug abuse deaths of teenagers aged 13-19 years between 1991 and 2006. Of these deaths, 96 (64.4%) were caused by the use of narcotic drugs only, 29 (19.5%) by both narcotics and cocaine, four (2.7%) by both narcotics and methylenedioxymethamphetamine, six (4.0%) by cocaine only, and 14 (9.4%) by volatile substances (e.g., butane, Freon, nitrous oxide, and propane). The annual death rate from drug abuse for teenagers increased from 1.4 deaths per 100,000 population in 1991 to 2.7 deaths per 100,000 population in 2006 (chi-square test for time trend, p<0.01). The increase in teenager drug abuse deaths occurred in 1999 and since has remained at a higher rate. Further analysis revealed that the increase in drug abuse deaths was attributable to a large degree to narcotic drugs, particularly heroin/morphine and methadone, and was confined to teenagers residing in the suburban and rural areas.     

Ketamine in non-hospital and hospital deaths in New York City

We reviewed all ketamine-positive deaths (87) examined at the New York City Office of Chief Medical Examiner over a two-year period (1997 to 1999). There were 15 non-hospital deaths with 12 due to acute multidrug intoxications, one due to sarcoidosis, and two due to physical injury (blunt and thermal). In no instance was a fatal intoxication caused exclusively by ketamine. Opiates (10/15), followed by amphetamines (7/15) and cocaine (6/15), were the most frequent co-intoxicants. Ethanol was found in only one death. The race of all decedents was white and the majority were men (11/15) between the ages of 18 and 30 years. The remaining 72 instances of positive ketamine findings were hospital deaths following surgical procedures or burns.     

Drowning deaths in toddlers and preambulatory children in South Australia

Infants who are preambulatory and toddlers who have only just learned to walk have particular characteristics that give them a unique susceptibility to drowning in certain circumstances. A study of drowning deaths in 32 infants and children <2 years of age in South Australia over a 35-year period from March 1963 to February 1998 was undertaken. The age range was 3 to 24 months (average, 15.4 months), and there was a male:female ratio of 21:11. Drownings occurred in home swimming pools (N = 10); baths (N = 9); waterways (i.e., rivers, irrigation ditches, sea; N = 5); buckets, bins, sinks (N = 4); and fish ponds (N = 3). Details were lacking in one case. Two cases raised questions regarding the manner of death and the possibility of inflicted injury. Specific problems that occur in the assessment of infant drownings include the vulnerability of infants to accidental and nonaccidental drowning, the absence of autopsy findings in inflicted drowning, and the lack of independent witnesses to the fatal episodes. Although the numbers of childhood drownings have declined in recent years, specific situations that remain dangerous for infants include unsupervised bathing and access to swimming pools, fish ponds, and industrial buckets containing water. Complete submersion does not have to occur for drowning to take place.     

Toxicological findings in victims of traumatic deaths.

The toxicological findings from 6037 analyses of viscera obtained from victims of traumatic death are used to correlate the relative incidence of carbon monoxide, ethyl alcohol, narcotics, hypnotics, analgesics, and tranquilizers-antidepressants in deaths occurring under the following circumstances: fire related, asphyxia by hanging, by use of plastic bags, from physical obstruction of trachae, and by drowning; traumatic injury from impact of moving train, fall from height, and occupational accident; traumatic injury to pedestrian, driver, and passenger from vehicular accidents; and from violent death by shooting, stabbing, strangulation, and beating. The influence of alcohol, narcotic drugs, and tranquilizers on carbon monoxide can be seen in some of these traumatic deaths. Ethanol alone and in combination with other drugs was present in 42.3% and 19.5% of driver and pedestrian victims, respectively, of vehicular accidents in the year 1974. Comparative analysis is presented for the toxicological data obtained on victims of homicide (shooting, stabbing, strangulation, and beating) in New York City and similar data reported for victims of homicide in Detroit. In New York City 45.9% of such victims died while under the influence of alcohol or narcotic drugs, or both, with methadone predominating in the latter category. Tissue concentrations of drugs found in victims of traumatic death are presented. Diphenylhydantoin, diazepam, meperidine, and slow-acting barbiturates were found in normal therapeutic levels. Higher concentrations of amitriptyline, chlorpromazine, propoxyphene, short-acting barbiturates, and methadone were observed. The concentration of methadone in blood and brain (0.13 +/- 0.14 mg/100 ml) and in liver (0.53 +/- 0.42 mg/100 ml) in cases of traumatic death are not different from those observed in deaths classified as due to methadone overdose.     

A survey of buprenorphine related deaths in Singapore

Buprenorphine is available in Singapore as substitution treatment for opioid dependence since 2002. This study surveys buprenorphine related deaths in Singapore between September 2003 and December 2004. The aims are to establish the autopsy prevalence of buprenorphine related deaths and the demographical and toxicological profile of the cases. Toxicological screening was performed for all unnatural deaths, deaths involving known drug addicts, as well as when autopsy revealed no obvious cause of death. Twenty-one cases had buprenorphine detected in post-mortem blood and/or urine samples. Eighteen were sudden deaths. There were two fatal falls from height and one death by hanging. All subjects were male. The age range was 24-48 years. Fourteen subjects were between 30 and 39 years of age. The mean age was 35 years. The majority (62%) were Chinese. Eleven (52%) were known drug abusers. For sudden deaths, two groups were identified. Six cases died from natural causes. Blood buprenorphine levels ranged from undetected (detected in urine) to 3.2 ng/mL (mean 1.4 ng/mL). Twelve cases were attributed directly and indirectly to mixed drug poisoning. Blood buprenorphine levels ranged from undetected (detected in urine) to 17 ng/mL (mean 3.2 ng/mL). Nineteen cases showed concurrent abuse of buprenorphine and benzodiazepine, diazepam being the most frequently detected, followed by nitrazepam and midazolam. The availability of buprenorphine as substitution therapy is associated with an increase in buprenorphine related deaths. The danger of co-abuse of buprenorphine and benzodiazepines is highlighted.     

Serum levels of digoxin in sudden cardiac deaths

Digoxin was determined in postmortem serum samples from 100 patients who died suddenly of cardiac disease. Twenty patients had digoxin levels below the therapeutic range. Twenty-one patients had normal values within the therapeutic range (1.2-2.5 nmol/l). In ten cases there was probably an overdosage. Another 15 patients had markedly elevated levels. No digoxin concentration was found (below 0.5 nmol/l) in 34 patients. The importance of determination of digoxin levels both by the clinician and the pathologist is stressed as well as the necessity of using a correct sampling technique at autopsy.     

中暑死与冻死的法医学鉴定

中暑死与冻死在法医学鉴定实际工作中并不常见,但由于其病理学表现往往不够明显,在法医实际鉴定时易被漏诊。本文作者查阅了国内外相关文献资料,并结合作者实际法医学鉴定经验将中暑死与冻死的法医学鉴定要点作出初步的总结。     

An epidemic of cocaine associated deaths in Utah

This article describes 15 cocaine associated deaths in Utah in a 3 1/2-month period in early 1984, compared to 6 cocaine associated deaths for all of 1983. Brief case histories of the 15 cases are presented along with data on age, sex, county of death, cause of death, association of the cocaine with the death, cocaine analytical methodology, and a summary of cocaine concentrations in blood and urine. In four of the cases, cocaine by injection was the cause of death, whereas the other cases had cocaine or metabolite detected incidentally. The epidemiology of a single, well-defined cocaine source is described and related to this transient, remarkable increase in cocaine associated deaths.     

Hazards of mattresses, beds and bedding in deaths of infants

Of 52 infants who had died suddenly and were referred to autopsy, nine had lain on adult water beds for the first time; five had died as a result of accidents; two had died on water beds; two were in beds with widely spaced slats; and one had died as a result of strangulation. Three deaths were due to overlying. Three other infants had been placed on sheepskin rugs for the first time and were found dead shortly thereafter. These infants ranged in age from 2 to 9 months, except for a severely mentally retarded nine-year-old with spastic paraplegia. We believe that a general warning should be issued concerning water beds and that soft bedding should not be used for infants. Infants should not be placed unattended or left to sleep on water beds; only beds recommended for infants should be used. Overlying of a young infant is most likely to occur on a water bed, or if the parent is obese or has consumed alcohol.     

Reenactment of circumstances in deaths related to restraint

Reenactment of the circumstances in deaths associated with restraint, utilizing participants and witnesses while memories are fresh, may help death investigators more accurately determine the cause of death. Two recent deaths in Ventura County that occurred during restraint are discussed. Within a day of the autopsies the restrainers agreed to participate in reenactments of the restraint process, utilizing live volunteers as subjects. They allowed videotaping. Deaths associated with restraint often have nonspecific autopsy findings. Timely reenactment of the circumstances of deaths associated with restraint can help death investigators more accurately determine the probable cause of death in these difficult cases.     

The perils of investigating and certifying deaths in police custody.

Procedures leading to the proper investigation and certification of deaths occurring in police custody are discussed. The importance of training and experience, of interchange of information between investigator and forensic pathologist, and of common sense in the pursuit of fairness toward this end is emphasized.     

Airway obstruction by laryngeal masses in sudden and homicidal deaths

We present two cases of autopsy detection of laryngeal masses with medico-legal implications. The first is a 56-year-old man who died suddenly of asphyxia due to upper airway obstruction caused by a large glosso-epiglottic retention cyst and glottic oedema. Hypothesis of medical liability was raised, due to delayed tracheotomy as the result of repeated failed attempts at oral intubation by various physicians. Difficult oral intubation due to the presence of a laryngeal mass in an asphyxiating subject requires rapid tracheotomy. The second case deals with a 43-year-old woman who died of asphyxia due to airway obstruction, as a result of injury of a cavernous laryngeal haemangioma after homicidal manual strangulation, with severe haemorrhagic infiltration of the surrounding soft tissues. Damage to laryngeal/hypopharyngeal masses should be considered as a possible sign of manual strangulation, as well as neck skin bruises/abrasions and laryngeal haemorrhages.