A 2‐Year Study of Δ 9‐tetrahydrocannabinol Concentrations in Drivers: Examining Driving and Field Sobriety Test Performance,,

From November 1, 2010 through November 30, 2012, 1204 whole‐blood samples were confirmed to contain THC alone or in combination with other drugs out of nearly 5000 Orange County, California, drivers suspected of driving under the influence of drugs. The goal of this study was to examine police reports and drug recognition expert evaluations of THC‐positive samples within this 2‐year time frame to determine whether there is a correlation between whole‐blood THC concentrations and field sobriety tests performance on DRE and non‐DRE evaluations. The FSTs prove to be sensitive to impairment by marijuana although as suspected, the findings of this study did not find a correlation between performance on field sobriety tests and the concentration of THC tested in whole‐blood samples. Driving behaviors were also examined and found to be similar to those seen in alcohol impairment. Future studies examining DRE findings are needed to confirm the results.     

Bacterial Cross‐contamination Potential Associated with Contaminated Currency

Previous studies have shown a significant amount of contaminants on paper currencies. It is important to study the transfer of microorganisms between paper currencies to determine whether it meets the level of a human health threat. This cross‐contamination potential was analyzed by seeding new US 1‐dollar bills with Bacillus thuringiensis, and pressing or rubbing them against clean currency to determine the amount of bacteria transfer to the unseeded currency. The transferred amount of bacteria was recovered, plated, incubated, and the colony‐forming units were quantified. Among the recovery methods tested, the most efficient method, vortexing for 10 min with a recovery efficiency of 40 ± 8.1%, was used in this analysis. The resulting transfer rates were 4.8%, 8.6%, and 14.3% when pressed for 24 h, 72 h, and rubbed together, respectively. These transferred amounts of bacteria are significant and have the potential to spread infectious diseases.     

Forensic Facial Comparison: Issues of Admissibility in the Development of Novel Analytical Technique

Much contemporary debate in forensic science concerns validity and admissibility of scientific evidence in court. In this paper, three current approaches to facial identification—image superimposition, photogrammetry, and morphological analysis—are considered with regard to criteria for scientific evidence in the United States, and England, and Wales. The aim of the paper is to assess the extent to which facial image comparison meets criteria of admissibility in these jurisdictions. The method used is a comparative evaluation of the methods of facial image comparison and their underlying premises against the range of admissibility criteria reported in court rulings and relevant judicial and scientific inquiries in the United States and the United Kingdom. While the techniques of facial image comparison are generally accepted within their practitioner communities, they are not tested, and their error rates are unknown. On that basis, the methods of facial image comparison would appear not to meet the anticipated standards. They are, nevertheless, admitted in court in the United States, and England, and Wales. This paper concludes that further research in science and law will be necessary to more definitively establish admissibility of facial image comparison evidence, as it will for other nascent and novel methods that are potentially influential in court proceedings.     

Species Identification of Cannabis sativa Using Real‐Time Quantitative PCR (qPCR),

Most narcotics‐related cases in the United States involve Cannabis sativa. Material is typically identified based on the cystolithic hairs on the leaves and with chemical tests to identify of the presence of cannabinoids. Suspect seeds are germinated into a viable plant so that morphological and chemical tests can be conducted. Seed germination, however, causes undue analytical delays. DNA analyses that involve the chloroplast and nuclear genomes have been developed for identification of C. sativa materials, but they require several nanograms of template DNA. Using the trnL 3′ exon‐trnF intragenic spacer regions within the C. sativa chloroplast, we have developed a real‐time quantitative PCR assay that is capable of identifying picogram amounts of chloroplast DNA for species determination of suspected C. sativa material. This assay provides forensic science laboratories with a quick and reliable method to identify an unknown sample as C. sativa.     

Simultaneous Identification of Four “Legal High” Plant Species in a Multiplex PCR High‐Resolution Melt Assay,

The international prevalence of “legal high” drugs necessitates the development of a method for their detection and identification. Herein, we describe the development and validation of a tetraplex multiplex real‐time polymerase chain reaction (PCR) assay used to simultaneously identify morning glory, jimson weed, Hawaiian woodrose, and marijuana detected by high‐resolution melt using LCGreen Plus^®. The PCR assay was evaluated based on the following: (i) specificity and selectivity—primers were tested on DNA extracted from 30 species and simulated forensic samples, (ii) sensitivity—serial dilutions of the target DNA were prepared, and (iii) reproducibility and reliability—sample replicates were tested and remelted on different days. The assay is ideal for cases in which inexpensive assays are needed to quickly detect and identify trace biological material present on drug paraphernalia that is too compromised for botanical microscopic identification and for which analysts are unfamiliar with the morphology of the emerging “legal high” species.     

Collecting and Analyzing DNA Evidence from Fingernails: A Comparative Study,,

Forensic practitioners and crime laboratories regularly collect and analyze fingernail evidence; however, the best techniques for processing such evidence have not been established. In this study, numerous aspects of fingernail evidence processing—collection of exogenous cells, transportation, purification of DNA, and STR analysis—were analyzed using fingernails harboring applied blood or epithelial cells from scratchings. Autosomal STR mixtures resulted when fingernails were soaked or swabbed, while scrapings rarely generated mixtures but exhibited allelic dropout. Y‐STRs yielded single source profiles, with scrapings again showing dropout. A silica‐based kit extraction recovered significantly more exogenous DNA than did organic extraction, neither of which was affected by nail polish. Swabbing nails in succession resulted in some cross‐contamination from exogenous material, while transporting nails together did not, although there was loss of exogenous cells. Optimized nail processing produced complete Y‐STR profiles of male volunteers from female fingernails following scratchings.     

Development of a PCR High‐Resolution Melt Assay for Artemisia absinthium (Wormwood) and a Triplex Assay with Two Additional “Unregulated Legal High” Species Datura stramonium (Jimson Weed) and Merremia tuberosa (Hawaiian Woodrose),

Artemisia absinthium (wormwood), a common ingredient in absinthe, contains the compound thujone, which is unregulated by the U.S. Drug Enforcement Agency. Thujone can cause an “unregulated legal high” in higher concentrations. The European Union limits thujone from Artemisia species to 35 mg/kg while the U.S. Food and Drug Administration requires less than 10 ppm to be “thujone‐free.” However, individuals can smoke or ingest A. absinthium in different forms. This study developed a polymerase chain reaction (PCR) high‐resolution melt (HRM) assay to detect and identify A. absinthium based on primer specificity, sensitivity, repeatability, and robustness. A triplex assay was performed with three “unregulated legal high” species: Datura stramonium, Merremia tuberosa, and A. absinthium; the PCR HRM assay detected and identified each plant at melt temperatures 77.42 ± 0.20°C, 83.88 ± 0.22°C, and 87.77 ± 0.15°C, respectively. The primer set developed distinguished A. absinthium from a variety of plant species and was successfully triplexed.     

The Prevalence of Encoded Digital Trace Evidence in the Nonfile Space of Computer Media,,

Forensically significant digital trace evidence that is frequently present in sectors of digital media not associated with allocated or deleted files. Modern digital forensic tools generally do not decompress such data unless a specific file with a recognized file type is first identified, potentially resulting in missed evidence. Email addresses are encoded differently for different file formats. As a result, trace evidence can be categorized as Plain in File (PF), Encoded in File (EF), Plain Not in File (PNF), or Encoded Not in File (ENF). The tool bulk_extractor finds all of these formats, but other forensic tools do not. A study of 961 storage devices purchased on the secondary market and shows that 474 contained encoded email addresses that were not in files (ENF). Different encoding formats are the result of different application programs that processed different kinds of digital trace evidence. Specific encoding formats explored include BASE64, GZIP, PDF, HIBER, and ZIP.     

An Unusual Case of Multiple‐Gunshot Suicide of an Alcohol‐Intoxicated Cancer Sufferer with Prolonged Physical Activity

Multishot firearm suicides are relatively rare and suggest the possibility of homicide. Physical activity following gunshots to the head, the neck, and the thorax does occur, and immediate incapacitation does not occur in every fatal gunshot wound that penetrates the head or perforates the heart. Cancer patients appear to be at increased suicide risk, but alcohol intoxication is less common in such cases. We present—to the best of our knowledge for the first time—a case of a 54‐year old, male, liver cancer sufferer, who under the influence of alcohol, discharged his revolver three times, suffered, among other wounds, a heart‐perforating wound, and died after c. 1.5 h, being able to talk until just before he died. Our case underlines the importance of keeping an open critical mind when dealing with multiple‐gunshot fatalities, especially when posttraumatic physical activity might be crucial in differentiating homicide from suicide.     

De Novo Advanced Adult‐Onset Offending: New Evidence from a Population of Federal Correctional Clients

Adult antisocial behavior is almost always predated by delinquency during childhood or adolescence; however, there is also evidence of adult‐onset criminal offending. This study examined this controversial subgroup of offenders using self‐reported and official data from a total population of federal correctional clients selected from the Midwestern United States. Difference of means t‐tests, chi‐square tests, and logistic regression models found that 11.7% of clients had an adult onset of offending and 2.7% of clients (n = 23) had an onset occurring at age 60 years or older. This group—introduced as de novo advanced adult‐onset offenders—had high socioeconomic status, mixed evidence of adverse childhood experiences, and virtually no usage of drugs with the exception of alcohol. These offenders were primarily convicted of social security and white‐collar crimes and evinced remarkably low psychopathology and criminal risk. More research is needed to replicate the phenomenon of de novo advanced adult‐onset offending.     

Detection of Anthrax and Other Pathogens Using a Unique Liquid Array Technology

A bead‐based liquid hybridization assay, Luminex^® 100?, was used to identify four pathogenic bacteria, Bacillus anthracis, Clostridium botulinum, Francisella tularensis subsp. tularensis, and Yersinia pestis, and several close relatives. Hybridization between PCR‐amplified target sequences and probe sequences (located within the 23S ribosomal RNA gene rrl and the genes related to the toxicity of each bacterium) was detected in single‐probe or multiple‐probe assays, depending on the organism. The lower limits of detection (LLDs) for the probes ranged from 0.1 to 10 ng. Sensitivity was improved using lambda exonuclease to digest the noncomplementary target strand. All contributors in 33 binary, ternary, and quaternary mixtures in which all components were present in a 1:1 ratio were identified with an 80% success rate. Twenty‐eight binary mixtures in which the two components were combined in various ratios were further studied. All target sequences were detected, even when the minor component was overshadowed by a tenfold excess of the major component.     

Rapid Quantitative Analysis of Multiple Explosive Compound Classes on a Single Instrument via Flow‐Injection Analysis Tandem Mass Spectrometry

A flow‐injection analysis tandem mass spectrometry (FIA MSMS) method was developed for rapid quantitative analysis of 10 different inorganic and organic explosives. Performance is optimized by tailoring the ionization method (APCI/ESI), de‐clustering potentials, and collision energies for each specific analyte. In doing so, a single instrument can be used to detect urea nitrate, potassium chlorate, 2,4,6‐trinitrotoluene, 2,4,6‐trinitrophenylmethylnitramine, triacetone triperoxide, hexamethylene triperoxide diamine, pentaerythritol tetranitrate, 1,3,5‐trinitroperhydro‐1,3,5‐triazine, nitroglycerin, and octohy‐dro‐1,3,5,7‐tetranitro‐1,3,5,7‐tetrazocine with sensitivities all in the picogram per milliliter range. In conclusion, FIA APCI/ESI MSMS is a fast (<1 min/sample), sensitive (~pg/mL LOQ), and precise (intraday RSD < 10%) method for trace explosive detection that can play an important role in criminal and attributional forensics, counterterrorism, and environmental protection areas, and has the potential to augment or replace several of the existing explosive detection methods.     

科学证据可采性标准的认识论反思与重构

科学证据的可采性是指是采纳某一科学证据作为证明某一事实的标准或条件。目前我国还没有建立明确的科学证据可采性标准,而在科学证据研究最发达的英美国家,科学证据可采性标准中的一些基本要素也是纠缠不清的。通过对科学证据可采性标准的历史考察和认识论反思,并根据科学证据在真相发现中的功能,可以尝试从内在属性和外在属性两个方面来审视科学证据可采性的结构。科学证据可采性的标准主要包括：科学证据本身的科学有效性、可靠性、科学相关性以及科学专家的可信性等。     

The over-citation of Daubert in forensic anthropology

The 1993 US Supreme Court decision Daubert v. Merrell Dow Pharmaceuticals, Inc. presented new guidance for the judicial assessment of expert witness evidence and testimony in the determination of admissibility. Despite the rarity of admissibility challenges to forensic anthropology evidence, Daubert is frequently cited in published forensic anthropology research. This study undertook a qualitative thematic analysis of forensic anthropology articles published in the Journal of Forensic Sciences to assess why authors continue to cite Daubert and express concerns over potential exclusion. The results show a significant increase in the number of articles that cite legal admissibility standards over time (p < 0.001). Authors frequently cite these standards to contextualize their results within the Daubert framework or to justify the need for their research. Notably, many articles present Daubert as a constraining force, misinterpreting the guidelines as rigid criteria or that they require methods to be strictly quantitative. However, Daubert was intended to be a flexible tool for judges—not a standard or instruction for scientists. While it was reasonable to reflect on the scientific rigor of methods in the wake of the Daubert decision, a new perspective is warranted in which forensic anthropologists shift their focus from trying to “satisfy” admissibility guidelines to adopting quality assurance measures that minimize error and ensure confidence in analytical results, and developing and using methods that are grounded in good science—which is important regardless of whether or not the results are ever the subject of a trial.     

STR Genotyping from a Dry‐Cleaned Skirt in a Sexual Assault Case

In this sexual assault case, the standard preliminary semen examinations could not confirm physically or biochemically whether the accused's semen had stained the victim's skirt because the skirt had been dry‐cleaned for stain removal and had been worn for more than a year after the assault. Fortunately, however, a photograph taken just after the assault was found in the court records that showed white stains on the checkered skirt. The locations of the stains were estimated based on the checkered pattern of the fabric, and microscopic examination using Baecchi's staining revealed the presence of spermatozoa. Further analysis indicated the male DNA profile generated from the sperm cells was consistent with the suspect's DNA using three multiplex STR typing systems for a total of 21 autosomal and 17 Y chromosomal short tandem repeats (STRs). Ultimately, the result of the DNA profile played a very useful role as additional evidence.     

A Review of Alcohol‐Impaired Driving: The Role of Blood Alcohol Concentration and Complexity of the Driving Task

The operation of a motor vehicle requires the integrity of sensory, motor, and intellectual faculties. Impairment of these faculties following the consumption of alcohol has been studied extensively through laboratory, closed‐course and on‐road driving, and epidemiological studies. The scientific literature was reviewed critically, with a focus on low‐to‐moderate blood alcohol concentrations (BAC ≤ 0.100%), to identify the most reliable determinants of alcohol‐impaired driving. Variables such as age, gender, driving skill, and tolerance were shown to have limited impact on impairment. It was concluded the most relevant variables are BAC and complexity of the driving task. The scientific literature provides a high degree of confidence to support the conclusion that a BAC of 0.050% impairs faculties required in the operation of a motor vehicle. Whether impairment is apparent depends upon the complexity of the driving task, which applies to both study design and actual driving.     

Genetic Identification of Communist Crimes’ Victims (1944–1956) Based on the Analysis of One of Many Mass Graves Discovered on the Powazki Military Cemetery in Warsaw,Poland

As the result of the communist terror in Poland, during years 1944–1956 more than 50,000 people died. Their bodies were buried secretly, and most places are still unknown. The research presents the results of identification of people buried in one of many mass graves, which were found at the cemetery Pow?zki Military in Warsaw, Poland. Exhumation revealed the remains of eight people, among which seven were identified genetically. Well‐preserved molars were used for the study. Reference material was collected from the closest living relatives. In one case, an exhumation of victim's parents had to be performed. DNA from swabs was extracted with a PrepFiler^® BTA Forensic DNA Extraction Kit and organic method. Autosomal, Y‐STR amplification, and mtDNA sequencing were performed. The biostatistical calculations resulted in LR values from 1608 to 928 × 10¹⁸. So far, remains of more than 50 victims were identified.     

Effects of Human Electro‐Muscular Incapacitation (HEMI) Devices on Cardiovascular Changes in Anesthetized Swine as Measured by Transesophageal Echocardiography (TEE)

The abundance of, and reliance upon, human electro‐muscular incapacitation (HEMI) devices, especially in law enforcement, has generated scrutiny and examination of these technologies. The purpose of this study was to examine cardiovascular effects resulting from typical (5 sec) and longer activation (20 sec) HEMI applications studying myocardial function and peripheral vascular system using a combination of invasive cardiovascular catheters and transesophageal echocardiography (TEE). Six healthy swine (Sus scrofa) 3–5 months in age and weighing between 60 and 86 kg were anesthetized and exposed to the TASER Model X26 waveform while transesophageal echocardiography was performed. Stroke volume was shown to statistically decrease during HEMI application indicating an increase in systemic vascular resistance, but HEMI application did not result in myocardial dysfunction (“cardiac stunning”).     

An Evidence‐Based Forensic Taxonomy of Windows Phone Communication Apps

Communication apps can be an important source of evidence in a forensic investigation (e.g., in the investigation of a drug trafficking or terrorism case where the communications apps were used by the accused persons during the transactions or planning activities). This study presents the first evidence‐based forensic taxonomy of Windows Phone communication apps, using an existing two‐dimensional Android forensic taxonomy as a baseline. Specifically, 30 Windows Phone communication apps, including Instant Messaging (IM) and Voice over IP (VoIP) apps, are examined. Artifacts extracted using physical acquisition are analyzed, and seven digital evidence objects of forensic interest are identified, namely: Call Log, Chats, Contacts, Locations, Installed Applications, SMSs and User Accounts. Findings from this study would help to facilitate timely and effective forensic investigations involving Windows Phone communication apps.     

Information‐Theoretical Assessment of the Performance of Likelihood Ratio Computation Methods

Performance of likelihood ratio (LR) methods for evidence evaluation has been represented in the past using, for example, Tippett plots. We propose empirical cross‐entropy (ECE) plots as a metric of accuracy based on the statistical theory of proper scoring rules, interpretable as information given by the evidence according to information theory, which quantify calibration of LR values. We present results with a case example using a glass database from real casework, comparing performance with both Tippett and ECE plots. We conclude that ECE plots allow clearer comparisons of LR methods than previous metrics, allowing a theoretical criterion to determine whether a given method should be used for evidence evaluation or not, which is an improvement over Tippett plots. A set of recommendations for the use of the proposed methodology by practitioners is also given.