The Role of Forensic Botany in Solving a Case: Scientific Evidence on the Falsification of a Crime Scene

Forensic botany can provide useful information for pathologists, particularly on crime scene investigation. We report the case of a man who arrived at the hospital and died shortly afterward. The body showed widespread electrical lesions. The statements of his brother and wife about the incident aroused a large amount of suspicion in the investigators. A crime scene investigation was carried out, along with a botanical morphological survey on small vegetations found on the corpse. An autopsy was also performed. Botanical analysis showed some samples of Xanthium spinosum, thus leading to the discovery of the falsification of the crime scene although the location of the true crime scene remained a mystery. The botanical analysis, along with circumstantial data and autopsy findings, led to the discovery of the real crime scene and became crucial as part of the legal evidence regarding the falsity of the statements made to investigators.     

植物物证的法医学应用

随着植物物证在案件侦破过程中的作用日益明显,应用植物学研究方法为刑事案件提供线索、证据的“法医植物学”越来越受到关注。法医植物学常用的实验技术有形态学检验、理化检验、分子遗传学检验等。本文通过整理法医植物学研究的相关文献及案例,以列举的形式简要阐述不同检验方法的利弊,总结法医植物学应用中需要注意的问题,供案件现场勘验时参考。     

Bullet Caliber and Type Categorization from Gunshot Wounds in Sus Scrofa (Linnaeus) Long Bone

Studies on ballistic trauma to the ribs and thorax, cranium, and long bones demonstrate the potential of obtaining a bullet caliber from an entrance wound. In order to validate prior research on caliber estimation in bone tissue and assess the viability of bullet type determination based on the macroscopic evidence at the entrance wound, thirty fleshed pork (Sus scrofa) shoulders (humeri) were shot with either lead or copper jacketed bullets in one of three calibers; 0.22, 9 mm, or 0.38. Overall, our findings are consistent with previous research indicating that calibers can be grouped into “small” and “large” categories. Bullet type, lead or copper jacket, can be ascertained based on cortical flaking and the analysis of materials deposited around the entry wound. The addition of this evidence holds value in cases where no firearm or ballistic evidence is recovered from a crime scene.     

Psychological autopsy in the investigation of serial neonaticides

While the use of psychological autopsies has at least a 50-year history in the investigation of equivocal deaths and suicides, we report a case where, after the discovery of a woman who died of natural causes, a subsequent search of her home found three deceased newborn infants. The infants were born on three separate occasions; the most recent was delivered approximately 2 weeks before the death of the mother. Using her own diaries and interviews with family and friends along with the physical autopsy and scene investigation data, we built a psychological autopsy that addressed the mother's mental state over the period of time when the infants' deaths took place. While the use of the psychological autopsy was not employed to distinguish the manner of death of the mother, it did provide explanatory power over circumstances of the crime scene and the behavioral disturbance of the mother.     

Bacterial Profiling of Soil For Forensic Investigations: Consideration of Ex Situ Changes in Questioned and Known Soil Samples

Soil, being diverse and ubiquitous, can potentially link a suspect or victim to a crime scene. Recently scientists have examined the microbial makeup of soil for determining its origin, and differentiating soil samples is well-established. However, when soil is transferred to evidence its microbial makeup may change over time, leading to false exclusions. In this research, “known” soils from diverse habitats were stored under controlled conditions, while evidence soils were aged on mock evidence. Limited quantities of soil were also assayed. Bacterial profiles were produced using next-generation sequencing of the 16S rRNA gene. Overall, known soils stored open at room temperature were more similar to evidence soils over time than were known soils stored bagged and/or frozen. Evidence soils, even as little as 1 mg, associated with the correct habitat 99% of the time, accentuating the importance of considering ex situ microbial changes in soil for its successful use as forensic evidence.     

Sudden Death Due To Acute Cocaine Toxicity—Excited Delirium in a Body Packer

Excited delirium denotes a life-threatening medical condition characterized by the acute onset of agitated and violent behavior that often results in a sudden and unexplained death. Cocaine-induced excited delirium refers to fatal cocaine intoxication with the following symptoms occurring sequentially: hyperthermia, delirium with agitation, respiratory arrest, and death. We present a case of cocaine-induced excited delirium in a cocaine “body packer” or a “mule”, specifically an individual who attempts to smuggle cocaine within the body. Investigators at the scene initially suspected homicide due to the victim's sharp and blunt force injuries. Three rubber packets containing cocaine were removed from the victim's rectum. Blood toxicological analysis revealed an alcohol concentration of 0.016 g/100 and cocaine >1 mg/L. The forensic pathologist should consider cocaine-induced excited delirium when an individual exhibits aggressive behavior, unexpected strength, and resistance to pain who dies suddenly. Further analysis should be performed during the scene investigation and autopsy for evidence of body packing.     

The Influence of Evidence on Animal Cruelty Prosecution and Case Outcomes: Results of a Survey

Two hundred prosecuting attorneys completed a survey concerning priorities in taking on animal cruelty cases and the factors that help or hinder prosecuting such cases. Respondents commented on the priority given such cases. Questions also addressed specific kinds of evidence that had been used to decide whether to take on a cruelty case and were used in court. Results showed that prosecutors most frequently relied upon “traditional” sources of evidence, including detailed medical and crime scene reports and good quality photographic evidence. Other sources of forensic evidence such as DNA, computer forensics, forensic accounting, blood, and trace evidence were rarely employed. Veterinary forensic evidence, including forensic necropsies and detailed medical reports, was viewed as an important factor by a majority of prosecutors in deciding whether to accept a case for prosecution and in achieving a successful outcome, but a need for additional training for investigators was indicated.     

The Need for an Interdisciplinary Approach in Forensic Sciences: Perspectives from a Peculiar Case of Mummification

The finding of a mummified body raises many problems, also because of the limits of the medico‐legal investigations in case of mummification. Psychological autopsy and behavioral analysis have demonstrated a significant impact in case of equivocal death. The mummified corpse of a woman was found sealed in a wardrobe during the death investigation of a 36‐year‐old man, later discovered to be the woman's son. The woman's corpse was well preserved and no external injuries were found. Autopsy could not ascertain the cause of death. The state of the premises and the writings on the walls offered an opportunity to investigate the man's psychological profile and to better understand how the events might have taken place. The role of an accurate investigative analysis of the crime scene is a cornerstone of forensic pathology and the case presented underlies the importance of an interdisciplinary approach in forensic sciences.     

“Bubbles”—A Spot Diagnosis

Abstract: Aspiration of blood is a phenomenon observed in violent and natural death scenarios. Bloodstain patterns evolving from expectoration of aspired blood may look suspicious of a violent genesis and thus mislead crime scene investigators. In the present case, a woman was found lying in a pool of blood on the kitchen floor. Furthermore, bloodstains covered her face, clothing, and surrounding furniture and walls. Bloodstain pattern analysis and medicolegal inspection of the suspected scene of crime were carried out and revealed dispersed stains with enclosed gas bubbles in the absence of signs of physical violence leading to the assessment of a natural manner of death. The bloodstains were attributed to expiration of blood because of an internal bleeding. Medicolegal autopsy confirmed the on‐site diagnosis as a fatal esophageal varix rupture was found.     

The Effects of Substance Use on Offender Crime Scene Behavior

Abstract:  Substance use has an effect on an individual's propensity to commit acquisitive crime with recent studies showing substance users more likely to leave forensic material at a crime scene. An examination of acquisitive crime solved in Northamptonshire, U.K., during 2006 enabled 70 crime scene behavior characteristics to be analyzed for substance and nonsubstance use offenders. Logistical regression analyses have identified statistically significant crime scene behavior predictors that were found to be either present at or absent from the crime scene when the offender was a substance user. Most significant predictors present were indicative of a lack of preparation by the offender, irrational behavior, and a desire to steal high value, easily disposed of, property. Most significant predictors absent from the crime scene were indicative of more planning, preparation, and execution by the offender. Consideration is given to how this crime scene behavior might be used by police investigators to identify offenders.     

Forensic Investigation of a Shawl Linked to the “Jack the Ripper” Murders

A set of historic murders, known as the “Jack the Ripper murders,” started in London in August 1888. The killer's identity has remained a mystery to date. Here, we describe the investigation of, to our knowledge, the only remaining physical evidence linked to these murders, recovered from one of the victims at the scene of the crime. We applied novel, minimally destructive techniques for sample recovery from forensically relevant stains on the evidence and separated single cells linked to the suspect, followed by phenotypic analysis. The mtDNA profiles of both the victim and the suspect matched the corresponding reference samples, fortifying the link of the evidence to the crime scene. Genomic DNA from single cells recovered from the evidence was amplified, and the phenotypic information acquired matched the only witness statement regarded as reliable. To our knowledge, this is the most advanced study to date regarding this case.     

Error Rates,Likelihood Ratios,and Jury Evaluation of Forensic Evidence

Forensic examiners regularly testify in criminal cases, informing the jurors whether crime scene evidence likely came from a source. In this study, we examine the impact of providing jurors with testimony further qualified by error rates and likelihood ratios, for expert testimony concerning two forensic disciplines: commonly used fingerprint comparison evidence and a novel technique involving voice comparison. Our method involved surveying mock jurors in Amazon Mechanical Turk (N = 897 laypeople) using written testimony and judicial instructions. Participants were more skeptical of voice analysis and generated fewer “guilty” decisions than for fingerprint analysis (B = 2.00, OR = 7.06, p = <0.000). We found that error rate information most strongly decreased “guilty” votes relative to no qualifying information for participants who heard fingerprint evidence (but not those that heard voice analysis evidence; B = −1.16, OR = 0.32, p = 0.007). We also found that error rates and conclusion types led to a greater decrease on “guilty” votes for fingerprint evidence than voice evidence (B = 1.44, OR = 4.23, p = 0.021). We conclude that these results suggest jurors adjust the weight placed on forensic evidence depending on their prior views about its reliability. Future research should develop testimony and judicial instructions that can better inform jurors of the strengths and limitations of forensic evidence.     

DNA Analysis of Natural Fiber Rope*

Abstract: When rope is found at a crime scene, the type of fiber is currently identified through its microscopic characteristics. However, these characteristics may not always unambiguously distinguish some types of rope from others. If rope samples contain cells from the plants of origin, then DNA analysis may prove to be a better way to identify the type of rope obtained from a crime scene. The objective of this project was to develop techniques of DNA analysis that can be used to differentiate between ropes made from Cannabis sativa L. (hemp), Agave sisalana Perrine (sisal), Musa textilis Née (abaca, “Manila hemp”), Linum usitatissimum L. (flax), and Corchorus olitorus L. (jute). The procedures included extracting the DNA from the rope, performing polymerase chain reaction (PCR) using the extracted DNA as a template, and analyzing the DNA products. A primer pair for PCR, chosen from within a chloroplast gene for the large subunit of ribulose bisphosphate carboxylase/oxygenase, was designed to be specific for plant DNA and complementary to the genes from all five plants. The resulting PCR fragments were approximately 771 base pairs long. The PCR fragments, distinguished through base sequence analysis or restriction enzyme analysis, could be used to identify the five different rope types. The procedure provides a useful addition to visual methods of comparing rope samples.     

Intentional Homicide: A Fifteen-Year Study (2000–2014) at the Department of Forensic Medicine,University of Rome “Sapienza”

This study analyzes postmortem records from 260 homicide cases autopsied by the Department of Forensic Medicine in Rome from 2000 to 2014. The victims were mainly males (74%) and young (61% aged from 21 to 50 years). Although the victims were mostly Italians, the number of foreign victims (33%) has increased since 1990, primarily due to immigration. The offenders frequently used firearms (39%), particularly in multiple murders. An increase in blunt (20%) and sharp force (32%) weapons was also seen. The primary crime scene was residential (42%), and the head was the most frequently injured body region. Male victims occurred frequently in the context of organized crime (7.6%). In family or intimate-sexual relationships, women were the majority of victims (8%). Forensic pathologists play an important role during investigation. They should consider all the information available to them, including autopsy information, crime scene information, and crime investigation data.     

Faux Blood Fingermark on Pistol: Latent Fingerprint Developed by Whole Blood

We present a case of a faux blood fingermark, wherein a natural latent fingerprint on the pistol at the crime scene was enhanced by the whole blood of the victim. A male was shot to death. The crime scene investigator did not find any blood fingermark during the collection of evidence, but a blood fingerprint was noticed in the firearms examination. We identified that the fingerprint was of the victim; a series of experiments on the nonporous substrate were then conducted; the death in this case was classified as a suicide. The phenomenon is interesting, and thus, calls for attention of the forensic community.     

Decapitation and Dismemberment of the Corpse: A Matricide Case*

Abstract: Dismemberment of a corpse has always been viewed by society to be a more hideous crime than the homicide itself. In this study, we present a case of a 57‐year‐old woman who was decapitated and her right arm and both hands were dismembered. It was determined that the victim was murdered and dismembered by her 33‐year‐old daughter, who had been receiving treatment for schizophrenia for 15 years. On the victim’s head and back there were 71 incised and stab wounds in total. They were superficial, except the five stab wounds which were connected to the right chest cavity and which incapacitated the victim. Although there is not a regulation for the act of dismembering the corpse in the Turkish Penal Code, since this type of case is rare, the crime scene and the autopsy findings were evaluated together with other pertinent data available in the literature.     

Fatal Overdose of Gamma‐hydroxybutyrate Acid After Ingestion of 1,4‐Butanediol

We report a case of fatal intoxication from 1,4‐butanediol (1,4‐BD), which was ingested by a young and “naïve” gamma‐hydroxybutyrate (GHB) consumer during a party with the co‐ingestion of alcohol, cannabis, and methylene‐dioxy‐methamphetamine. The following drug concentrations were found using gas chromatography coupled with mass spectrometry on autopsy samples and on a cup and a glass found at the scene: 20,350 mg/L (bottle) for 1,4‐BD; 1020 mg/L (femoral blood), 3380 mg/L (cardiac blood), 47,280 mg/L (gastric content), and 570 mg/L (vitreous humor) for GHB. The concentration of GHB is difficult to interpret in forensic cases due to the possibility of an endogenous production of GHB. The variable tolerance of the user may also modify the peri‐ and postmortem GHB concentrations. This case underscores the need to have many different sources of toxicology samples analyzed to avoid the hypothesis of endogenous production of GHB.     

Concentrations of Opiates and Psychotropic Agents in Polydrug Overdoses: A Surprising Correlation Between Morphine and Antidepressants

Abstract: The relationship between postmortem concentrations of morphine and co‐detected psychoactive drugs in fatal overdoses is examined. Morphine and other drugs were detected in 161 medicolegal autopsy cases. Subsets of these morphine‐positive cases based on drug class were established, including opioids, antidepressants, ethanol, benzodiazepines, and “other.” Each subset was split into high or low concentration groups based on median drug concentrations. Morphine concentrations of the [high] and [low] groups were compared, with no significant difference in morphine concentration identified in the opioid, ethanol, or benzodiazepine subsets. The “other” drug class was too heterogeneous for statistical assessment. Morphine concentrations did show a significant direct relationship (p = 0.01) with antidepressants, namely increased concentrations of antidepressant drugs are associated with an increased concentration of morphine. This trend probably remains even after excluding cocaine‐positive cases. The unsuspected finding that postmortem concentrations of antidepressants positively correlate with morphine levels may be important in the treatment of depression in drug addicts.     

Forensic Identification of Blood in the Presence of Contaminations Using Raman Microspectroscopy Coupled with Advanced Statistics: Effect of Sand,Dust, and Soil

Body fluid traces recovered at crime scenes are among the most common and important types of forensic evidence. However, the ability to characterize a biological stain at a crime scene nondestructively has not yet been demonstrated. Here, we expand the Raman spectroscopic approach for the identification of dry traces of pure body fluids to address the problem of heterogeneous contamination, which can impair the performance of conventional methods. The concept of multidimensional Raman signatures was utilized for the identification of blood in dry traces contaminated with sand, dust, and soil. Multiple Raman spectra were acquired from the samples via automatic scanning, and the contribution of blood was evaluated through the fitting quality using spectroscopic signature components. The spatial mapping technique allowed for detection of “hot spots” dominated by blood contribution. The proposed method has great potential for blood identification in highly contaminated samples.     

采用纯CO气体杀人案件的分析

一氧化碳(CO)气体中毒致人死亡多见于自杀和意外事件,采用纯CO气体杀人的案例国内罕有报道。本文报道了一起采用瓶装纯CO气体致人中毒死亡的案例,作案方式隐蔽,作案手段鲜见,且伪造了作案现场,给侦查带来一定困难。经刑事技术人员认真细致地现场勘查、尸体检验和物证提取检验,结合调查访问,最终明确了案件性质,认定了犯罪嫌疑人,全面还原了其作案过程。笔者总结分析了该案刑事技术工作中的要点和难点,希望能对同行们有所帮助。