Trace DNA success rates relating to volume crime offences

In this study, 252 trace DNA samples (from handled surfaces) from 201 burglary, robbery and drugs cases were compiled to assess success rates and to interpret the value of trace DNA evidence in volume crime investigations. The average amount of DNA recovered from the trace DNA samples collected was 1.7 ng. Full or major (12 or more alleles) profiles were recovered from 14% of samples. Samples from firearms and burglary points of entry were the least successful. Mixtures were recovered from 21% of samples, presenting a case for the collection of more elimination profiles to enable more samples to be used for database purposes. The research highlighted the difficulties in collecting data relating to the success rates of samples. Computerised automation of this process would be extremely beneficial in the assistance of policy development, method application, training, and investigative usefulness.     

Value of DNA evidence in detecting crime

DNA material is now collected routinely from crime scenes for a wide range of offences and the timely processing of the DNA is seen as key to its success in investigating and detecting crime. An analysis of DNA material recovered from the volume crime offences of residential burglary, commercial burglary, and theft of motor vehicle in Northamptonshire, U.K., in 2004 has enabled the DNA to be categorized into seven sources. Further analysis using a logistical regression has revealed a number of predictors, other than timeliness, that greatly influence whether the DNA material recovered from a crime scene enables the crime to be detected. The results indicate that a number of these predictors are of statistical significance and may be just as relevant in determining whether DNA successfully detects the crime as the timeliness of the processing of the DNA material. The most significant predictor was found to be investigating officer accreditation with location, quantity, and type of DNA material at the crime scene also being relevant. Accreditation of the Crime Scene Examiner recovering the DNA material was found not to be significant. Consideration is given to where further emphasis is needed by the U.K. police service to maximize the opportunities to detect volume crime with DNA.     

Narcotics and crime: A causal modeling approach

The present study examines the relationships between narcotics use and criminality utilizing a confirmatory structural equation modeling approach. Latentvariable and manifest-variable models are used to represent causal relationships between narcotics use and criminality in both the postaddiction and the pretreatment periods of the addiction career. Latent-variable models include a preexisting deviance construct as an exogenous factor, and manifest-variable models include a measure of drug trafficking, or dealing, as an influencing variable. Both inclusions are made as an attempt to minimize specification error in the models. The results are consistent in showing that, while simultaneous relationships between narcotics and criminality are clearly demonstrable, the prediction of either variable from the other across time cannot be demonstrated. It is concluded that causal relationships between narcotics and criminality are probably not characterized by an appreciable or identifiable time lag. Other theoretical considerations suggested by the modeling results are discussed, such as the role of idiosyncratic approaches to the economics of maintaining addition.     

Organized crime: A social network approach

This article applies the anthropological approach of social networktheory to the study of organized crime in its local, domestic and transnational contexts. It argues that a social network approach transcends existing criminological paradigms like organizational, patron-client and enterprise theories in that it emphasizes a common supposition held by each paradigm – that human relationships form the basis for organized criminal activity. By understanding the dynamics behind these relationships and the networks they create, one can subsequently gain a clearer picture of organized criminalactivity across time, space and culture.     

The effectiveness of forensic evidence in the investigation of volume crime scenes

This study investigates the effectiveness of forensic evidence in UK volume crime investigations. The main aim was to identify characteristics of forensic evidence that influence its effectiveness in converting detections into criminal charges, as well as to critically consider the effectiveness of a recent service level agreement (SLA) implemented by Wiltshire Police, which aimed at reducing CSI attendance. The sample consisted of 445 police recorded cases received from Wiltshire Police. Presence or absence and location-related characteristics of fingerprint, DNA, and footwear evidence were evaluated on the effectiveness of forensic evidence and examined within the contexts of different volume crimes. Results showed a high level of correlation in converting detections into criminal charges where the presence of DNA, footwear, and multiple evidence types was recorded; and a positive correlation between forensic evidence ineffectiveness and presence of fingerprints, particularly in residential burglaries. Differences between individual offence types were expressed. The most prominent feature influencing the effectiveness of forensic evidence was found to be related to the movability of the exhibit associated with the recovered evidence, with DNA recovered from non-movable items presenting the strongest effectiveness. Cases processed after the implementation of the SLA did not show significant differences in forensic evidence effectiveness as compared to cases processed prior to the SLA, however, they demonstrated a lack in effectiveness of DNA evidence. The findings of the current research provide a better understanding of the contextual influences on the potential of forensic evidence and can support improvement of crime scene screening and CSI resource deployment.     

A single approach to the recovery of DNA and firearm discharge residue evidence.

The Laboratory of the Strathclyde Police Forensic Support Department extracts DNA from cellular material recovered from garments submitted as evidence. The standard method used an adhesive tape attached to a plastic or acetate support. This paper demonstrates a method whereby a single sample, recovered from clothing, can be examined for Firearm Discharge Residue and then extracted for DNA.     

Age structure and crime rates: The conflicting evidence

Because arrest rates are especially high for teenagers and young adults, criminologists have long contended that age structure changes affect crime trends. In recent years, however, this belief has been drawn into question because crime has not declined even though high-crime age groups have shrunk. We argue that the age/crime relationship is probably exaggerated because the high arrest rates for younger persons are due partly to their lesser ability to escape arrest, younger persons commit more group crime, and the age structure of victims should be taken into account. We then review 90 studies that regress crime rates on age structure; only a small minority consistently finds significant relationships. Because of methodological problems in this research, one cannot conclude that the age/crime relationship does not exist, but the weight of evidence shows that forecasts based on demographic trends are not likely to be helpful.     

Digital evidence and the crime scene

Many criminal investigations maintain an element of digital evidence, where it is the role of the first responder in many cases to both identify its presence at any crime scene, and assess its worth. Whilst in some instances the existence and role of a digital device at-scene may be obvious, in others, the first responder will be required to evaluate whether any ‘digital opportunities’ exist which could support their inquiry, and if so, where these are. This work discusses the potential presence of digital evidence at crime scenes, approaches to identifying it and the contexts in which it may exist, focusing on the investigative opportunities that devices may offer. The concept of digital devices acting as ‘digital witnesses’ is proposed, followed by an examination of potential ‘digital crime scene’ scenarios and strategies for processing them.     

The relationship between injustice and crime: A general strain theory approach

Purpose

Connect General Strain Theory (GST) and the organizational justice literature by examining how different types and combinations of major forms of injustice (distributive, procedural, and interactional), and resultant anger, may increase the likelihood that individuals respond to strain with crime.

Method

Logit and OLS regressions are used to analyze survey data obtained from a vignette that was randomly assigned to a sample of undergraduates. The vignette presented a distributive injustice and manipulated the additional presence of procedural and interactional injustice. Respondents rated their likelihood of intending to engage in a violent act and a non-violent deviant act.

Results

As expected, multiple types of injustice foster the intention of responding to injustice with crime. In addition to a distributive injustice, the presence of procedural injustice predicts violence, while interactional injustice predicts excessive drinking. Moreover, anger mediates the injustice-crime relationship, although this effect is more substantial for the association between procedural injustice and violence.

Conclusions

The relationship between injustice and crime is complex. Different forms of injustice can affect the propensity for crime through anger. Further research is encouraged to identify the criminogenic potential of certain types of combinations of injustice on the experience of negative emotions and crime.     

The likelihood approach to compare populations: a study on DNA evidence and pitfalls of intuitions

The paper follows on from earlier work [Taroni F and Aitken CGG. Probabilistic reasoning in the law, Part 1: assessment of probabilities and explanation of the value of DNA evidence. Science & Justice 1998; 38: 165-177]. Different explanations of the value of DNA evidence were presented to students from two schools of forensic science and to members of fifteen laboratories all around the world. The responses were divided into two groups; those which came from a school or laboratory identified as Bayesian and those which came from a school or laboratory identified as non-Bayesian. The paper analyses these responses using a likelihood approach. This approach is more consistent with a Bayesian analysis than one based on a frequentist approach, as was reported by Taroni F and Aitken CGG. [Probabilistic reasoning in the law, Part 1: assessment of probabilities and explanation of the value of DNA evidence] in Science & Justice 1998.     

A rational approach to the principles and practice of crime scene investigation: I. Principles.

This paper proposes a structured approach to crime scene investigation that may be applied to the wider aspects of criminal investigation. The approach is an adaptation of the hypotheticodeductive method. The investigator begins with observation of the scene leading to a cycle of hypotheses creation and testing with other information being supplied only after the initial scene examination and hypotheses creation. The recording of observation, hypotheses creation and testing, and information received creates an audit trail of the investigative process. The method seeks to minimise observer bias by providing a rational and recorded approach to crime scene investigation.     

法医物证DNA自动化检验技术体系的研究

目的建立自动化工作站同步提取不同种类涉案法医生物检材DNA的新方法。方法选用TECAN Freedom EVO100．4、75—2型自动化提取、加样工作站,采用磁珠法及Chelex-100法对各类涉案生物检材进行DNA提取、PCR扩增、毛细管电泳检测其STR分型,进行比较测试。在“全国公安机关DNA数据库应用系统”中建立并应用实验室信息管理系统（LIMS）模拟实施规范化DNA检案。结果1552份各类检材,采用工作站-磁珠法提取DNA效果最佳,STR检测成功率为95％,工作站-Chelex法为88％;二者分别与其手工提取法比较,成功率无明显差异。92个样本同期检测,自动化工作站较手工操作DNA检案时间可缩减1．25倍。结论工作站域珠法提取涉案检材DNA,可获得满意的STR分型结果。应用LIMS管控,可有效防控污染,明显提高检案效率及鉴定质量。     

Application of plant DNA markers in forensic botany: genetic comparison of Quercus evidence leaves to crime scene trees using microsatellites

As highly polymorphic DNA markers become increasingly available for a wide range of plant and animal species, there will be increasing opportunities for applications to forensic investigations. To date, however, relatively few studies have reported using DNA profiles of non-human species to place suspects at or near crime scenes. Here we describe an investigation of a double homicide of a female and her near-term fetus. Leaf material taken from a suspect's vehicle was identified to be that of sand live oak, Quercus geminata, the same tree species that occurred near a shallow grave where the victims were found. Quercus-specific DNA microsatellites were used to genotype both dried and fresh material from trees located near the burial site and from the material taken from the suspect's car. Samples from the local population of Q. geminata were also collected and genotyped in order to demonstrate that genetic variation at four microsatellite loci was sufficient to assign leaves to an individual tree with high statistical certainty. The cumulative average probability of identity for these four loci was 2.06x10(-6). DNA was successfully obtained from the dried leaf material although PCR amplification was more difficult than amplification of DNA from fresh leaves. The DNA profiles of the dried leaves from the suspect's car did not match those of the trees near the crime scene. Although this investigation did not provide evidence that could be used against the suspect, it does demonstrate the potential for plant microsatellite markers providing physical evidence that links plant materials to live plants at or near crime scenes.     

A general theory of crime and computer crime: An empirical test

Computer crime has become a global issue and continues to rapidly grow; however, few studies had examined the applicability of a general theory of crime in explaining computer deviance. Using a panel of 2,751 Korean youths, the current study examined whether low self-control theory can be useful as a theoretical framework for explaining computer crime. The results indicated the applicability of low self-control theory in explaining both illegal download of software and illegal use of others’ personal identification online. Consistent with the theory's prediction, opportunity variables, especially hours of computer use, were found to be significant predictors of computer crime. The shortcomings of the current research and the directions for future research were discussed.     

Beyond crime seriousness: Fitting the punishment to the crime

This paper presents an exposition of how the factorial survey approach may enhance empirical assessments of the complex judgment principles involved in public views of just punishments for convicted offenders. Ratings of the appropriateness of sentences given across 50 typical crimes obtained from a household sample (N=774) of the Boston SMSA and several special-interest samples in 1982 are examined in three alternative ordinary least-squares (OLS) regression equations. These analyses show there is not a one-to-one direct relationship between public perceptions of the seriousness of criminal acts and desired sanctions. Crime seriousness is modified by the characteristics of the offenders and victims and by the consequences of the crimes. Preferred punishments also vary in severity by demographic, experiential, and attitudinal characteristics of the persons who make the judgments.