DNA Preparation from Sexual Assault Cases by Selective Degradation of Contaminating DNA from the Victim

Abstract:  The standard method to purify sperm DNA from vaginal swabs taken from rape victims is to selectively digest the victim's epithelial cells to solubilize the victim's DNA, and then separate the soluble DNA from the intact sperm by centrifugation. A different approach to removing the soluble victim's DNA is to selectively degrade it using a nuclease, DNase I. DNase I reduces the amount of soluble DNA by over 1000-fold, while having virtually no effect on the sperm DNA remaining in the sperm head and inaccessible to the enzyme. Nuclease inactivation and sperm lysis then yield a soluble, pure male DNA fraction. An aliquot of soluble DNA is removed prior to nuclease addition to provide the victim's fraction. Vaginal swabs taken at defined time points following consensual sex and taken from rape victims were processed using the nuclease method or the standard method and the nuclease method gave superior short tandem repeat profiles.     

Chemical Enhancement Techniques of Bloodstain Patterns and DNA Recovery After Fire Exposure*

Abstract: It is common in forensic casework to encounter situations where the suspect has set a fire to cover up or destroy possible evidence. While bloodstain pattern interpretation, chemical enhancement of blood, and recovery of deoxyribonucleic acid (DNA) from bloodstains is well documented in the literature, very little information is known about the effects of heat or fire on these types of examinations. In this study, a variety of known types of bloodstain patterns were created in a four‐room structure containing typical household objects and furnishings. The structure was allowed to burn to flashover and then it was extinguished by firefighters using water. Once the structure cooled over night, the interior was examined using a bright light. The bloodstains were evaluated to see if the heat or fire had caused any changes to the patterns that would inhibit interpretation. Bloodstain patterns remained visible and intact inside the structure and on furnishings unless the surface that held the blood was totally burned away. Additionally, a variety of chemical techniques were utilized to better visualize the patterns and determine the possible presence of blood after the fire. The soot from the fire formed a physical barrier that initially interfered with chemical enhancement of blood. However, when the soot was removed using water or alcohol, the chemicals used, fluorescein, luminol, Bluestar^®, and Hemastix^®, performed adequately in most of the tests. Prior to DNA testing, the combined phenolphthalein/tetramethyl benzidine presumptive test for the presence of blood was conducted in the laboratory on samples recovered from the structure in an effort to assess the effectiveness of using this type of testing as a screening tool. Test results demonstrated that reliance on obtaining a positive presumptive result for blood before proceeding with DNA testing could result in the failure to obtain useful typing results. Finally, two DNA recovery methods (swabbing the stain plus cutting or scraping the stain) were attempted to evaluate their performance in recovering samples in an arson investigation. Recovery of DNA was more successful in some instances with the swabbing method, and in other instances with the cutting/scraping method. Therefore, it is recommended that both methods be used. For the most part, the recovered DNA seemed to be unaffected by the heat, until the temperature was 800°C or greater. At this temperature, no DNA profiles were obtained.     

Presidential hegemony and democratic backsliding in Latin America, 1925–2016

ABSTRACT

Does the executive's institutional hegemony represent a risk to the survival of democracy? By hegemony, we refer to the president's ability to control other institutions, particularly the legislature and judiciary. To answer this question, we develop two indices of presidential hegemony and analyze the duration of democratic regimes in 18 Latin American countries between 1925 and 2016. The results show that executive hegemony is a major driver of democratic instability. This finding is robust to non-linear effects and to potential endogeneity in the relationship between presidential power and democratic backsliding. Our findings challenge traditional concerns about executive-legislative deadlock, and have significant implications for the nascent literature on democratic backsliding, which highlights executive aggrandizement as a risk factor.     

Is there still a place for gene patents in Australia? Implications of recent United States and European case law

This article considers the ramifications of recent United States and European litigation relating to patents claiming rights to genes associated with hereditary forms of breast cancer (the so-called BRCA genes) for recently commenced Australian litigation relating to the same subject matter. The article is contextualised with brief summaries of the relevant patent law, the science of genetics, the history of the BRCA genes and an overview of the activities of the patent holder. The analysis of first instance and appeal decisions on the validity of the United States BRCA patents shows the final outcome is still highly uncertain in that jurisdiction, while the European litigation provides little assistance in predicting the outcome of the Australian action. This article concludes that the outcome of the Australian litigation is an issue that cannot be determined with any certainty due to the lack of specific, relevant precedents both in Australia and in other jurisdictions.     

LAWYERS AND MENTAL HEALTH PROFESSIONALS WORKING TOGETHER: RECONCILING THE DUTIES OF CONFIDENTIALITY AND MANDATORY CHILD ABUSE REPORTING

Lawyers are increasingly finding themselves working in conjunction with a social worker and/or a psychologist. This dynamic can be found in organizations that take a multi‐disciplinary approach to the law, such as New York City's Legal Aid Society and Lawyers for Children. Collaborative law is another such example. Collaborative law is an increasing trend in family law; it provides a divorcing couple the opportunity to work with professionals from different disciplines, without being subject to the court system. While a multi‐disciplinary approach to the law has the ability to maximize the value of representation, it also can create tension when inconsistent duties are imposed by conflicting professional obligations. A major area of conflict is between the lawyer's duty to maintain client confidences and the mental health professional's duty to report child abuse. This Note discusses the important policies behind these opposing duties. The Note recommends amending state child abuse and neglect laws in order to eliminate the conflict between the professions' duties and allow lawyers and mental health professionals to work together more harmoniously. Amending state child abuse and neglect laws will allow for mental health professionals working with a lawyer who represents a client the same reporting duties as lawyers in the process.     

Changes in the Rules of the Lawmaking Process and the Success of Presidential Bills: Chile, 1990–2018

This article assesses the effect of changes in the lawmaking process on the success of the president’s legislative agenda, distinguishing between within-term success (bills that passed during the term) and overall success (including bills that passed after the president left office). With the 2064 presidential bills introduced in seven terms (1990–2018) in Chile’s presidential system, we assess the impact of changes in lawmaking rules on within-term (59.9%) and overall success (70.6%). Changes that decrease attributions of the president and create more opportunities for executive-legislative bargaining—including concurrent elections—increase the chances of success of presidential bills. The use of presidential urgency motions, an agenda-setting tool, makes bills more likely to pass, but the issuance of many urgency motions undermines the bill’s chances to succeed. Presidential bills introduced early in the term and those on issues where there is more policy convergence are more likely to pass.