Technological innovation in the recovery and analysis of 3D forensic footwear evidence: Structure from motion (SfM) photogrammetry

The recovery of three-dimensional footwear impressions at crime scenes can be a challenge but can also yield important investigative data. Traditional methods involve casting 3D impressions but these methods have limitations: the trace is usually destroyed during capture; the process can be time consuming, with a risk of failure; and the resultant cast is bulky and therefore difficult to share and store. The use of Structure from Motion (SfM) photogrammetry has been used widely to capture fossil footprints in the geological record and while there is a small body of work advocating its use in forensic practice the full potential of this technique has yet to be realised in an operational context. The availability of affordable software is one limiting factor and here we report the availability of a bespoke freeware for SfM recovery and subsequent analysis of for footwear evidence (DigTrace). Our aim here is not to provide a rigorous comparison of SfM methods to other recovery methods, but more to illustrate the potential while also documenting the typical workflows and potential errors associated with an SfM based approach. By doing so we hope to encourage further research, experimentation and ultimately adoption by practitioners.     

THE DYNAMICS OF CRIME REGIMES*

Crimes have many features, and the mix of those features can change over time and space. In this article, we introduce the concept of a crime regime to provide some theoretical leverage on collections of crime features and how the collections of features can change. Key tools include the use of principal components analysis to determine the dimensions of crime regimes, visualization methods to help reveal the role of time, summary statistics to quantify crime regime patterns, and permutation procedures to examine the role of chance. Our approach is used to analyze temporal and spatial crime patterns for the city of Los Angeles during an 8‐year period. We focus on the number of violent crimes over time and their potential lethality.     

犯罪治理数字孪生体研究

犯罪治理的复杂特性迫切需要新科技介入研究。随着数字化时代的到来,犯罪治理现代化的研究和建设采取智能化手段已成可能,以此来提升精准犯罪治理的程度,达到更好的治理效果。针对处于复杂高阶多维的犯罪治理社会实体,结合数字孪生高逼真行为仿真特性和人工智能深度学习强大的数据挖掘能力,引入数字孪生进行犯罪治理现代化研究,从而构建犯罪治理数字孪生体。通过在虚拟空间可视化与分析实现犯罪治理现代化管理、预测预警、态势预判、模拟仿真、计算试验等,实现实时监测数据驱动下的犯罪在线治理,为犯罪治理现代化探索新思路。     

Development of a Dundee Ground Truth imaging protocol for recording indoor crime scenes to facilitate virtual reality reconstruction

Early and accurate visualisation of a crime scene is highly desirable such that a rapid, agile, and informed decision-making process can be undertaken by an investigative team. We present a new standard operating procedure for imaging an indoor scene using DSLR cameras conventionally used by crime scene investigators and examiners. The standard operating procedure (SOP) enables the systematic photography of indoor spaces in such a way that the Structure from Motion (SfM) photogrammetry technique can be implemented, allowing the scene to be recreated in Virtual Reality (VR). To demonstrate the method’s validity, we compare two VR-rendered representations of an example scene using (a) photographs taken by an experienced crime scene examiner using a conventional photographic method and (b) photographs taken by a novice photographer following the developed SOP.     

A REEXAMINATION OF THE ETIOLOGY OF URBAN CRIME

Ecological analysis of crime rates has been a traditionally important approach to analyzing the causes of crime. Over the years, this approach has profited from the use of increasingly sophisticated data analysis techniques. A recent article in this journal on intracity crime rates offered such an analytic refinement—with the discovery of similar curvilinear relationships between both personal and property crime and customary socioeconomic predictors Such a finding for both types of crime is quite different from the results indicated in previous research. The present article reexamines comparable data on urban crime, adding further statistical and theory-based refinements to the analysis The results here show distinctive relationships for property and personal crime. This paper serves, then, to integrate careful empirical analysis into available criminogenic theory and into the conventional wisdom of ecological research.     

Are US Crime Rates Really Unit Root Processes?

Existing research has uncovered little evidence against the hypothesis of US crime rates being unit root processes, despite the uncomfortable implications of this assumption. In light of this, the present paper draws upon noted changes in the temporal patterns of US crime rates since 1960 to undertake an informed approach to testing of the unit root hypothesis which incorporates two potential points of structural change. The results obtained show the unit root hypothesis to be rejected for all classifications of criminal activity examined over the period 1960 to 2007. In addition, the dates of the detected breakpoints are supported by a variety of arguments available in the existing criminology literature concerning alternative determinants of crime and their movements. Interestingly, a difference is observed in the nature of the breaks detected for violent and property crimes. However, potential explanations for this are again found in theoretical arguments available in the criminology literature. Finally, the implications of the current findings for the properties of crime, its subsequent statistical analysis and past and future research are discussed.     

The extraction and infrared identification of gamma-hydroxybutyric acid (GHB) from aqueous solutions

The chemical analysis of gamma-hydroxybutyric acid (GHB) in most forensic laboratories is complicated by the highly polar nature of the GHB molecule, which makes it unsuitable for direct analysis by gas chromatography (GC). Consequently, a popular analytical approach is to convert GHB into the corresponding lactone or a derivative compound that is then identified by mass spectrometry employed in conjunction with GC (GC/MS). An alternative approach is presented here where GHB may be isolated as a free acid specie from complex aqueous solutions employing a liquid-liquid extraction technique. This approach can yield a relatively pure residue of GHB that presents an infrared transmission spectrum that is sufficiently distinct for identification purposes. Infrared spectroscopy (IR) is a very popular technique that is available to most crime laboratories. The liquid-liquid extraction behavior of GHB is examined in detail and the uniqueness of the infrared spectrum is discussed.     

How to avoid driving DNA caseworkers crazy: CaseSolver,an expert system to investigate complex crime scenes

DNA analyses can be used for both investigative (crime scene-focused), or evaluative (suspect-focused) reporting. Investigative, DNA-led exploration of serious crimes always involves the comparison of hundreds of biological samples submitted by the authorities for analysis. Crime stain comparisons include both evidence to evidence profiles and reference to evidence profiles. When many complex DNA results (mixtures, low template LT-DNA samples) are involved in the investigation of a crime, the manual comparison of DNA profiles is very time-consuming and prone to manual errors. In addition, if the person of interest is a minor contributor, the classical approach of performing searches of national DNA databases is problematic because it is realistically restricted to clear major contributors and the occurrence of masking and drop-out means that there will not be a definitive DNA profile to perform the search with.CaseSolver is an open source expert system that automates analysis of complex cases. It does this by three sequential steps: a) simple allele comparison b) likelihood ratio (LR) based on a qualitative model (forensim) c) LR based on a quantitative model (EuroForMix). The software generates a list of potential match candidates, ranked according to the LRs, which can be exported as a report. The software can also identify contributors from small or large databases (e.g., staff database or 1 mill. individuals). In addition, an informative graphical network plot is generated that easily identifies contributors in common to multiple stains. Here we describe recent improvements made to the software in version v1.5.0, made in response to user requirements during intensive casework usage.     

Metadata Retention as a Means of Combatting Terrorism and Organised Crime: A Perspective from Australia

On October 13, 2015, new laws came into force in Australia requiring telecommunications service providers to retain and store their ‘metadata’ for 2 years so that it remains available for analysis by anti-terrorism strategists and organised crime fighters. But there are ongoing issues associated with this legislative approach, including the threats to privacy thereby, and concerns that the retention system can be circumvented entirely. This paper will outline the legal and criminological questions that need to be explored in order to help policymakers work through these issues so that an appropriate balance can be struck between forestalling crime and terrorism using all available electronic means, and not unduly curtailing the legitimate rights to privacy that citizens in modern democracies currently expect to enjoy.     

Spatial analysis of crime and region in the united states

The regionality of crime has been presented, debated, and questioned for over a centruy of this Nation’s history, usually involving a segmental approach to crime rates or treating the various crime rates separate from one another. This paper, using states as a real unit of analysis, develops two general crime dimensions using discriminant function analysis. These two dimensions, based upon complete estimation, demonstrate the discriminating power of crime profiles in assessing regionality. Also, region as an independent variable is shown to possess strong explanatory power regarding crime patterns. Although crime viewed at the state and regional level is highly generalized, it does draw attention to spatial and temporal consistencies in the general crime pattern. This level of analysis and this paper allows a greater understanding about the country and integrates available information on crime variations within our society. Finally, implications of this study for the current criminal justice system in the united States are discussed.     

The prediction and control of organized crime: A risk assessment instrument for targeting law enforcement efforts

Linking isolated instances of organized crime in a systematic way can inform law enforcement in identifying high-risk activities and markets and prioritizing them according to objective factors known to be associated with organized crime. There are five ways in which risk assessment organized crime can be achieved. Improvements to data collection, utilizing a team approach to gather information, identifying common elements in organized crime incidents, understanding the parameters of a risk assessment instrument, and connecting organized crime risk assessment to the implementation of law and policy are practical ways in which organized crime activity can be better anticipated, investigated, and prevented. Connecting isolated incidents to organized crime through better information from offenders, victims, and police is possible with teams of investigators, researchers, and analysts. An organized crime risk assessment tool is presented that offers systematic analysis of opportunity factors, the criminal environment, and harm potential among the seventeen risk factors identified. Risk assessment can be used to evaluate the influence of organized crime in local jurisdictions, and the impact of new laws and policies that affect commerce and criminal opportunities.     

Toward the safety society: Police agencies and environmental planning

The authors of this paper outline one approach to crime prevention which has recently become available - participation by police agencies in the environmental planning process. Two environmental management devices, the environmental impact assessment process and the general plan, are described and opportunities for police agency involvement are detailed. The contribution of public safety personnel to environmental management is seen as residing in two areas: precicting the effects of a project on the demand for police services, and suggesting ways in which a project may be designed with a view to the prevention of crime. In the latter context, the literature in environmental design and environmental psychology is reviewed for findings relevant to the creation of a safe environment.     

Geomatic techniques in forensic science: A review

The purpose of this review paper is to highlight various geomatic techniques that crime scene reconstructionists or forensic practitioners can use to document different kinds of scenes, highlighting the advantages, disadvantages, and when best to use each technology. This paper explores geomatic techniques such as a total station, photogrammetry, laser scanners and structured light scanners and how they can be used to reconstruct crime scenes. The goal of this paper is not to discredit manual methods, as they are long standing and reliable, but instead to shed light on alternative methods that may produce equally or more accurate results with a more visually appealing final product. It is important for law enforcement and forensic professionals to understand the advantages and disadvantages of each technique, knowing when certain techniques should be used (and when they should not), and being able to revert to traditional methods if required.     

Bite mark documentation and analysis: the forensic 3D/CAD supported photogrammetry approach

Bite mark identification is based on the individuality of a dentition, which is used to match a bite mark to a suspected perpetrator. This matching is based on a tooth-by-tooth and arch-to-arch comparison utilising parameters of size, shape and alignment. The most common method used to analyse bite mark are carried out in 2D space. That means that the 3D information is preserved only two dimensionally with distortions. This paper presents a new 3D documentation, analysis and visualisation approach based on forensic 3D/CAD supported photogrammetry (FPHG) and the use of a 3D surface scanner. Our photogrammetric approach and the used visualisation method is, to the best to our knowledge, the first 3D approach for bite mark analysis in an actual case. The documentation has no distortion artifacts as can be found with standard photography. All the data are documented with a metric 3D measurement, orientation and subsequent analysis in 3D space. Beside the metrical analysis between bite mark and cast, it is possible using our method to utilise the topographical 3D feature of each individual tooth. This means that the 3D features of the biting surfaces and edges of each teeth are respected which is--as shown in our case--very important especially in the front teeth which have the first contact to the skin. Based upon the 3D detailed representation of the cast with the 3D topographic characteristics of the teeth, the interaction with the 3D documented skin can be visualised and analysed on the computer screen.     

Visualization of Latent Fingerprint Corrosion on a Discharged Brass Shell Casing

Abstract:  Latent fingerprint visualization on discharged shell casings can provide good forensic evidence, particularly if the casing is recovered at the scene of a crime where a firearm has been discharged. Unfortunately, visualization of such latent fingerprints when they were deposited prior to discharge of the firearm is problematic as both increased temperature and abrasive friction can inhibit fingerprint visualization with conventional techniques. We present a case study that demonstrates latent fingerprint visualization on a discharged shell casing recovered 14 years ago from the scene of a homicide. Previous cyanoacrylate fuming of the casing had failed to reveal any fingerprints. We use a visualization technique in which a conducting carbon powder adheres preferentially to latent fingerprint corrosion of the casing surface, following the application of a potential of 2.5 kV to the casing. This technique presents opportunities for the review of old cases and for consideration of its use in current cases.     

Of bogus hunters,queenpins and mules: the varied roles of women in transnational organized crime in Southern Africa

Organized crime scholars have paid scant attention to gender and stereotyped roles of women in the commission of organized crime activities. Traditionally, organized crime is seen as a form of criminality perpetrated by men only. Women are usually portrayed as victims of organized crime or as “mean girls”, girlfriends, wives, lovers of brides of notorious gangsters and mobsters. In the southern African context, little historical or comparative data is available on the role of women in organized crime. Existing data is basic and proceeds on the assumption of gender-neutrality or the implied male composition of organized crime groups. The link of women to organized crime is one of suffering and exploitation. However, in reality women fulfill varied roles and functions within transnational organized crime networks in the region. In some instances, they are the foot soldiers of drug and human trafficking syndicates. Sometimes they are the intermediaries or powerful matriarchs at the apex of transnational organized crime networks. Reliant on empirical findings undertaken for a regional 3-year project on organized crime trends in southern Africa, this paper will examine the dynamism of the role of women in organized crime in the region and argues that women play a multifaceted role with implications for themselves, their families, society and organized crime. Gender mainstreaming within scholarly literature and policy research is in nascent stages, this paper pleads for a more gender-sensitive approach to organized crime analysis.     

Towards rational and evidence-based crime policy

Rational crime policy constitutes a basic goal for society. If, however, evidence-based, cost-efficient crime prevention is the standard, there is little indication that current policies—including programs, laws, and court decisions—are rational. To support that assessment, this article uses an evaluation research perspective to highlight five prominent problems with extant crime policies: (1) a lack of empirical assessment of the need for them; (2) a range of design issues, including gaps between crime theory and policy, and, most notably, the pursuit of silver bullet solutions; (3) a range of implementation issues, including disjunctures between ideal and actual practice; (4) the lack of rigorous impact evaluations and the sometimes misplaced emphasis on them; and (5) a scarcity of cost-efficiency analyses for guiding investment decisions. It then discusses the implications of these problems and suggests steps that can be taken to place crime policy on a more evidence-based foundation.     

Predictive Policing as a New Tool for Law Enforcement? Recent Developments and Challenges

Decision-making processes are increasingly based on intelligence gained from ‘big data’, i.e., extensive but complex datasets. This evolution of analyzing complex data using methods aimed at prediction is also emerging within the field of quantitative criminology. In the context of crime analysis, the large amount of crime data available can be considered an example of big data, which could inform us about current and upcoming crime trends and patterns. A recent development in the analysis of this kind of data is predictive policing, which uses advanced statistical methods to make the most of these data to gain useable new insights and information, allowing police services to predict and anticipate future crime events. This article presents the results of a literature review, supplemented with key informant interviews, to give insight into what predictive policing is, how it can be used and implemented to anticipate crime, and what is known about its effectiveness. It also gives an overview of the currently known applications of predictive policing and their main characteristics.