Scene Evidence Research Articles

Differences in Forensic Science Views and Needs of Law Enforcement: A Survey of Michigan Law Enforcement Agencies

A survey of Michigan law enforcement agencies was undertaken in order to determine their forensic science views and needs, and if they differed by size, type of law enforcement agency, and location. Most ranked forensic science as very important in criminal cases, and about half had specific officers or units dedicated to the collection of evidence. Most sent the evidence to a state crime lab. For applicants and new recruits, the knowledge areas deemed most important were interviewing techniques, crime scene documentation, evidence collection, and latent fingerprint analysis. Latent evidence, evidence collection, crime scene documentation, and interviewing techniques were ranked the most important areas to be covered in training seminars.

Los Alamos scientist creates gun that can collect crime scene evidence

Los Alamos scientist creates gun that can collect crime scene evidence

Factfinders' Judgments Concerning Forensic Identification Science Testimony

Forensic identification science rests upon the notion that certain attributes of inanimate objects, persons, or even the residuum of certain behavior contain so much variability that it is possible to associate evidence from a crime scene with the source of that evidence. But serious scientists have long realized that, for reasons physical, statistical and psychological, such credulousness reflects a fundamental misunderstanding of these techniques. Outside of DNA typing, forensic identification has no random match probability data to share with factfinders, and such experts generally assert that their examination indicates that the crime scene evidence and the defendant's sample share a common source, or some comparable formulation. Our research is concerned with the effects of the kind of testimony that is given, or which could be given, for the numerous other forensic identification sciences that have been in existence much longer than DNA typing (e.g., fingerprints, handwriting, microscopic hair comparison); these fields have no scientific basis of the sort that DNA typing does, and must stand instead on the foundation of the personal experience and judgment of their practitioners, who must support their claims in court not with empirical data but with testimonial assurances. How would such expert testimony be received if it included more complete and candid descriptions of how they reached their findings and the more limited meaning of those findings? In three experiments we examined the impact on judges and jurors of different ways of expressing the meaning of a forensic match. Overall, the data revealed that what factfinders conclude from the evidence varied as a function of the ways in which the expert's findings were expressed and whether or not the limitations of the accuracy of forensic identification science were presented.

The Social and Legal Construction of Suspects

▪ Abstract DNA profiling and searchable databases enhance the ability of policing organizations to search for criminal suspects. In many respects, these technologies are incorporated within traditions of police work, supplementing familiar “subjective” methods of constructing suspects. In other ways, however, the construction of DNA databases in Britain, the United States, and elsewhere shifts criminal investigation toward suspect populations and statistical suspects. Not only is DNA evidence used to confirm that a criminal suspect is the source of crime scene evidence, it can be used to search freely through a suspect population for a possible source of such evidence. This method, commonly known as database trawling, comprises a new way of constructing suspects, one that bears close connections with new data mining technologies for prospectively identifying terrorist suspects.

Criminal profiling: developing an effective science and practice

Criminal Profiling: Developing an Effective Science and Practice aims to transform criminal profiling into a credible science and practice that will reliably aid law enforcement investigation. Authors Scotia J. Hicks and Bruce D. Sales painstakingly critique the state of criminal profiling today and find the practice of criminal profiling to be an art more than an established science, lacking clear links among crime scene evidence and offender motives, personality, and behavior. With no firm scientific basis for their judgments, profilers differ in their conclusions and recommendations, rendering profiling problematic as a law enforcement tool. This book tackles this problem squarely, exploring in detail how a science of profiling may be constructed and tested. The comprehensive new approach offered here builds on existing practice and research and calls for empirical information that can lead to a sound new science of criminal profiling.

Low copy number: Interpretation of evidence results

Crime scene evidence and samples from decomposed or skeletal remains have usually low copy number (LCN), with templates containing less than 100 pg of DNA. The choice of the best extraction methods as well as sensitive and robust STRs is crucial to obtain good results. However, in many situations, it is also necessary to make adaptations to standard protocols, such as increase in the number of amplification cycles (even when commercial kits are used) or the injection time in capillary sequencers. A set of four amplifications was made, with 28 (two of them), 32 and 34 cycles. To the samples with 28 PCR amplification cycles was added more enzyme and two other amplifications with 4 and 6 cycles was performed. Results were analysed and discussed.

Organizing the Argentinean Combined DNA Index System (CODIS)

As proposed our Latin American Society for Forensic Genetics in June 17th, 2003, last year the Argentinean Minister of Justice, Security and Human Rights signed the Resolution #415/2004 (full text available in Spanish in www.slagf.org), which created the DNA Fingerprint Registry, similar to the American CODIS. The Registry blends computer and DNA technologies into an effective tool for fighting violent crime. The system uses two indexes to generate investigative leads in crimes where biological evidence is recovered from the crime scene. The Convicted Offender index contains DNA profiles of individuals convicted of felony sex offenses (and other violent crimes). The Forensic index contains DNA profiles developed from crime scene evidence. The Registry utilizes computer software to automatically search these indexes for matching DNA profiles. Like the American CODIS, this is a system of pointers; the database only contains information necessary for making matches. Profiles stored contain a specimen identifier, the sponsoring laboratory's identifier, the initials (or name) of DNA personnel associated with the analysis, and the actual DNA characteristics. Matches made among profiles in the Forensic Index can link crime scenes together; possibly identifying serial offenders. Based on a match, police can coordinate separate investigations, and share leads developed independently. Matches made between the Forensic and Convicted Offender indexes ultimately provide investigators with the identity of the suspect(s). Following are the major enhancements planned for the next years: There are differences among province laws, so the first step is to make them compatible.•Optimize software performance for Local, Province and National Indexes.•Select the labs with high-quality standards. Quality controls in Latin America are conducted by the Latin American Society for Forensic Genetics and the Spanish and Portuguese Speaking Group of the ISFG.•Training courses to DNA analysts from participating laboratories. Until now, the training courses in Latin America are organized by the Latin American Society for Forensic Genetics.•Begin operation of the National DNA Index System.•Proliferate the installed base to include all crime laboratories performing DNA analysis.

Perceptions of the validity and utility of criminal profiling among forensic psychologists and psychiatrists.

Criminal profiling is the process of using crime scene evidence to make inferences about potential suspects, including personality characteristics and psychopathology. An exploratory Internet survey of forensic psychologists and psychiatrists was conducted to examine their experiences with and opinions about profiling and to determine whether referring to profiling as “criminal investigative analysis” had any impact on these opinions. About 10% of the 161 survey respondents had profiling experience, although more than 25% considered themselves knowledgeable about profiling. Fewer than 25% believed that profiling was scientifically reliable or valid, and approximately 40% felt that criminal investigative analysis was scientifically reliable or valid. Although the scientific aspects of profiling lacked support, respondents viewed profiling as useful for law enforcement and supported profiling research.

Diabetic Ketoacidosis – A possible Complicating Factor in Deaths associated with Drug Overdose

Two cases are described where diabetic ketoacidosis was found in conjunction with significant levels of prescription drugs. Case 1: A 45-year-old woman with a history of insulin-dependent diabetes mellitus was found to have Armanni-Ebstein nephropathy characteristic of hyperglycaemia with a vitreous humour glucose level of 63.1 mmol/L and a beta-hydroxybutyrate level of 14.25 mmol/L. Ancillary toxicological evaluation revealed a lethal level of sertraline (2.5 mg/L), with an elevated level of methadone (0.23mg/L). Death was due to diabetic ketoacidosis complicating mixed drug toxicity. Case 2: A 27-year-old man with a history of insulin-dependent diabetes mellitus was found to have Armanni-Ebstein nephropathy with a vitreous humour glucose level of 51.7 mmol/L and a beta-hydroxybutyrate level of 18.6mmol/L. Ancillary toxicological evaluation revealed a potentially lethal level of methadone of 0.39mg/L. Death was attributed to diabetic ketoacidosis complicating methadone toxicity. These cases demonstrate a situation where drug toxicity led to diabetic ketoacidosis resulting in death most likely from a combination of factors. Measuring vitreous humour glucose and beta-hydroxybutyrate levels is important in individuals with histories, or scene evidence, of insulin-dependent diabetes mellitus, in addition to toxicological screening when there is evidence of possible drug taking. It appears that drug intoxication in both cases had impaired the ability to administer insulin, resulting in the development over time of diabetic ketoacidotic states. Lethal mechanisms were, therefore, more complex than simple drug toxicity or diabetic ketoacidosis in isolation.

The Impact of DNA Exonerations on the Criminal Justice System

The emergence of post-conviction DNA testing has had profound effects on the American criminal justice system. Although changes in the formal legal landscape are readily noticeable, the DNA exonerations have also produced other consequences that may have potentially more significance. To comprehend and assess the influence of post-conviction DNA testing one must examine more than just the law on the books. After some introductory material, Part I of this essay looks at repercussions DNA exonerations are having on the basic operation of the criminal justice system, Part II examines new statutes that govern procedures for post-conviction DNA testing requests, and Part III briefly considers how these current developments may affect Supreme Court jurisprudence.Post-conviction DNA testing has evolved in little more than a decade. Before 2000, only two states, New York and Illinois, had statutes that authorized post-conviction DNA testing. In other jurisdictions, no formally authorized procedures existed that allowed inmates to make requests for DNA testing of crime scene evidence.

Is Obtaining an Arrestee's DNA a Valid Special Needs Search under the Fourth Amendment? What Should (and Will) the Supreme Court Do?

In the past twenty years, advances in forensic DNA technology have revolutionized the American criminal justice system. The use of forensic DNA testing in America began in 1987, and its demonstrated scientific accuracy quickly led jurisdictions to accept expert testimony regarding DNA matches between suspects and crime scene evidence. Wielding the power to exonerate the innocent and apprehend the guilty, the use of DNA identification technology has become an indispensable resource for prosecutors and law enforcement officials, as well as for defense lawyers representing persons falsely accused or wrongfully convicted of crimes they did not commit. As states began to compile DNA profiles from convicted offenders, the need for a repository for these profiles resulted in the DNA database.Originally, DNA databases included only “those classes of offenders with a high recidivism rate, such as sex offenders and violent felons.” Recognizing the crime-solving potential of this technology, state legislatures soon began to expand the scope of DNA database statutes to include broader classes of offenders.

Fatal Falls from a Height: Two Case Studies

Two case studies are presented involving fatal falls of adult females from a height. One involved a launch at low speed from a balcony, and one involved a launch at high speed from the top of a cliff. Crime scene evidence obtained on the balcony itself provided a strong indication of homicide, but subsequent investigation showed that the fall was accidental. No crime scene evidence was obtained for the cliff fall since the fall initially appeared to be just another suicide from a popular suicide spot. Subsequent investigations indicated homicide based on measurements of cliff height, horizontal distance to the impact, and available runup distance, plus measurements of possible run, jump, and throw speeds. It was found that a female weighing 61 kg (134 lb) can be thrown at speeds up to 4.85 m/s by a strong male, more than enough to account for the estimated launch speed (4.5 m/s). Given the available 4.0 m runup distance, it was found that women of better than average rather than elite athletic ability can dive at speeds of about 3.5 m/s or jump feet first at speeds of about 4.0 m/s, both being less than the estimated launch speed. The decedent had no athletic ability and landed head first after falling through a height of 29 m.

Review of: Analysis and Interpretation of Fire Scene Evidence

Abstract Analysis and Interpretation of Fire Scene Evidence bills itself as “essentiall for forensic scientists, insurance investigators, fire departments, and other specialists involved in the investigation of fire scenes. It also benefits attorneys and judges involved in arson cases.” That may be true of some parts of this book, but it is definitely a mixed bag. When assembling a cast of distinguished authors to put together a volume like this, a light touch by the editors is frequently all that is required, but in this case, the editors' touch seems to be entirely weightless. The title is misleading, as there is very little actual guidance of “interpretation” in the book.

Is Obtaining an Arrestee's DNA a Valid Special Needs Search Under the Fourth Amendment? What Should (and Will) the Supreme Court Do?

In the past twenty years, advances in forensic DNA technology have revolutionized the American criminal justice system. The use of forensic DNA testing in America began in 1987, and its demonstrated scientific accuracy quickly led jurisdictions to accept expert testimony regarding DNA matches between suspects and crime scene evidence. Wielding the power to exonerate the innocent and apprehend the guilty, the use of DNA identification technology has become an indispensable resource for prosecutors and law enforcement officials, as well as for defense lawyers representing persons falsely accused or wrongfully convicted of crimes they did not commit. As states began to compile DNA profiles from convicted offenders, the need for a repository for these profiles resulted in the DNA database.Originally, DNA databases included only “those classes of offenders with a high recidivism rate, such as sex offenders and violent felons.” Recognizing the crime-solving potential of this technology, state legislatures soon began to expand the scope of DNA database statutes to include broader classes of offenders.

An Empirical Test of Holmes and Holmes’s Serial Murder Typology

This article presents the results of an empirical test of Holmes and Holmes’s serial murder classification scheme. Crime scene evidence from 100 U.S. serial murders, each the third in a distinct series, was content analyzed. The co-occurrence of content categories derived from the crime scene material was submitted to smallest space analysis. The features characteristic of the category of “power or control” killings were found to be typical of the sample as a whole, occurring in more than 50% of cases, and thus did not form a distinct type. Limited support was found for aspects of the lust, thrill, and mission styles of killing, but this support drew attention to differences in the ways victims were dealt with, through mutilation, restraints, or ransacking their property rather than the motivations implicitly inferred in Holmes and Holmes’s typology. The current results are presented as an empirical basis for the classification of serial killings on which more detailed models can be built.

The forensic science needs of law enforcement applicants and recruits: A survey of Michigan law enforcement agencies*

Many colleges and universities offer forensic science courses ranging from a single introductory class to majors. Previous research has not addressed how valuable these courses are to undergraduate criminal justice students who aspire to enter the law enforcement field. A random sample of law enforcement agencies in Michigan were surveyed. Seventy-eight percent of respondents agreed that knowledge of forensic science was important and 46% preferred that applicants have a forensic science background prior to hiring. The knowledge areas deemed most important were interviewing techniques, crime scene documentation, evidence collection, and latent fingerprint analysis.

Crime scene investigation: An exercise in generating and analyzing DNA evidence*

AbstractThe goal of this project is to introduce students to molecular biology techniques using an experimental setting that inspires both scientific and personal interest. The project is designed as a small group apprenticeship for gifted high school juniors or seniors who can spend full time in a sponsor's laboratory for at least 1 week. The students begin by examining evidence from a mock crime scene that consists of hair samples from the crime scene and from five potential suspects. Students extract DNA from the hair samples and amplify a hypervariable region within the mitochondrial genome using the polymerase chain reaction. Amplified products are then sequenced and compared with the crime scene sequence using DNA alignment software. In consecutive projects, students from four different schools successfully identified the suspect who matched the crime scene evidence. This project is a valuable learning tool not only due to the comprehensive introduction to molecular biology techniques but also because it helps the students to connect scientific exploration with well publicized media events and provides a window into potential career opportunities in the field of molecular biology.

A new chemical aid for criminal investigation: dyes and latent prints

Criminalistics is a field in which there are many opportunities for the practical application of chemical reagents and the use of analytical methods that provide answers to enigmas at crime scenes. Common reagents in biochemical and medical test methods can be useful for criminalistics (forensic science). Dyes are one type of reagent that can be used in obtaining crime scene evidence. This work describes a new application of CI Solvent Black 3 dye in the location of latent fingerprints. The results show that CI Solvent Black 3 can be successfully applied in the location and development of recent and non‐recent latent fingerprints on porous surfaces.

The Myth of Hidden Ireland: The Corrosive Effect of Place in The Quiet Man

In households across the United States, the mere mention of John Ford's 1952 film The Quiet Man can have an unnerving effect upon an individual's equanimity. This is particularly true for many Irish Americans of the baby boom era who remember growing up under its influence. Quite simply, that movie has become the embodiment of all that was maudlin, manipulative, and embarrassing about the culture of their forebears, both in this country and in Ireland. At first glance, one can find ample evidence in scene after scene of The Quiet Man to reinforce this view. Like other Ford films from the era, it calls to mind the swaggering optimism of a culture still proud of the part that it played in the defeat of the Axis powers in World War II and still free of any trace of self-doubt that might have curbed the arrogance of an unquestioned belief in the American way of doing things. More particularly, and with far more serious consequences, for the casual viewer The Quiet Man seems to play upon all of the simplistic images of Irish life and character that xenophobic Yankee isolationists and sentimental expatriates had alternately disdained and celebrated in print, on the stage, and ultimately, in electronic media from the mid-nineteenth century onward.

’Religiöse Nachwehen’ in Schnitzler’s Anatol

Taking as its starting‐point the middle scene of Schnitzler’s Anatol, entitled ‘Denksteine’, this short essay sees in specific expressions used in the same scene evidence for a residual?—if subliminal?—authority exerted by moral imperatives derived from the Judaeo‐Christian tradition. In a diluted, secularised form these shape Anatol’s notion of ‘love’ and account for the impulse repeatedly to vow ‘ewige Liebe’, not‐withstanding his own inclinations and past practice. The resultant inner division in Anatol between ‘Intellekt’ and ‘Bedu¨rfnis’ is seen in relation to Nietzsche’s reference to ‘religiöse Nachwehen’ (in Menschliches, Allzumenschliches) as one form of the ‘nihilism’ of the period, as diagnosed by Nietzsche.