Context effects in forensic science: a review and application of the science of science to crime laboratory practice in the United States.

This article discusses the phenomenon of "context effects" by reviewing the findings and practices of a range of scientific fields, including astronomy, physics, biology, medicine, and especially the relevant research and theory from psychology. Context information, such as expectations about what one is supposed to see or conclude, has been found to have a small but relentless impact on human perception, judgment, and decision-making. The article then considers the vulnerability of forensic science practice to context effects, and concludes by suggesting that forensic science adopt practices familiar in other fields of scientific work, in particular blind or double-blind testing and also the use of evidence line-ups.     

Suicide risk in outpatients with specific mood and anxiety disorders

The present study examined the relationships between specific anxiety, mood disorders, levels of hopelessness, and suicide ideation. The sample consisted of 606 outpatients recruited from several psychiatric settings. It was found that dysthymia was significantly associated with hopelessness. Patients presenting major depressive episode with higher anxiety symptoms had significantly increased scores on the hopelessness scale. Major depressive episode and bipolar disorder, but not dysthymia, were significantly associated with higher levels of suicide ideation. Increased levels of anxiety symptoms in patients with dysthymia were associated with increased levels of suicide ideation, while increased depressive symptoms in patients with specific phobia and generalized anxiety disorder were associated with significantly lower levels of suicide ideation. The findings suggest that depressive disorders, but not anxiety disorders, constitute risk for suicide. Moreover, the differentiation between a depressive and an anxiety disorder as the principal diagnosis, as well as the assessment of anxiety-level symptoms in patients with major depressive episode and dysthymia, seems of special relevance when assessing suicide risk.     

Child and adolescent survivors of suicide

Suicide in a family is distressing for each and every member. Children and adolescents bereaved by suicide are known to be more at risk of suffering from a variety of psychiatric problems, especially affective disorders. A group of children and adolescents who experienced a suicidal death in the family were assessed for psychiatric problems as well as for social adjustment. The findings suggest that the bereaved children and adolescents are at elevated risk for major depressive disorder, posttraumatic stress disorder, and impaired social adjustment.     

Searching for graves using geophysical technology: field tests with ground penetrating radar,magnetometry, and electrical resistivity

Field experiments were conducted using three types of geophysical equipment in a variety of situations. The goal of the study was to ascertain the relative utility of this technology for non-geophysical expert forensic professionals searching for buried human remains. The study concludes that the equipment should be used with caution after a critical evaluation of specific field conditions, and more refinement of technical methods and skills should be developed.     

Mechanisms of unexpected death in tuberous sclerosis

Tuberous sclerosis complex is a protean autosomal dominant disorder characterized by multifocal tissue lesions arising from defects in cellular migration, proliferation, and differentiation. It has an association with sudden death. In the current study, review of all cases of sudden death due to tuberous sclerosis was undertaken at the Forensic Science Centre in Adelaide, Australia from 1991 to 2001, in addition to an analysis of cases from the literature. There were two local cases where unexpected death had occurred in individuals with known tuberous sclerosis, involving a 31-year-old male (epilepsy), and a 24-year-old female (massive hemorrhage into a renal angiomyolipoma). Fatal mechanisms in cases of tuberous sclerosis may be associated with underlying cardiovascular, renal and cerebral abnormalities. Sudden death may be due to cardiac arrhythmia, epilepsy, and intra-tumoral hemorrhage with additional complications including cardiac outflow obstruction, obstructive hydrocephalus, aneurysm rupture, and spontaneous pneumothorax. An awareness of the highly variable tissue manifestations of tuberous sclerosis and the mechanisms that may be responsible for death is necessary to establish correctly the diagnosis in occult cases (possibly with molecular confirmation), and to chart accurately organ changes in individuals with established disease.     

Trends in explosive contamination

This study sought to assign a rough order of magnitude for the amount of explosive residue likely to be available in real-world searches for clandestine explosives. A variety of explosives (TNT, TATP, HMX, AN, RDX, PETN) in various forms (powder, flake, detonating cord, plastic) were carefully weighed or cut into containers, and the amount of residue inadvertently remaining on the work area, hands, or containers was quantified. This was used to evaluate the spillage potential of each explosive. The adhesion of each explosive to a glass surface was quantified from amount of explosive adhering to the inside of a glass vial into which the explosive had been placed and then removed by vigorous tapping. In powdered form, most of the explosives--TNT, PETN, RDX, HMX, and TATP--exhibited similar spillage and adhesion to glass. However, PETN as sheet explosive and plasticized RDX (C-4), showed very little potential to contaminate surfaces, either by spillage or adhesion to glass.