Gun-related Crime Research Articles

Taking aim at crime: evaluating evidence in a crime gun intelligence approach

ABSTRACT Identifying effective strategies to combat firearm-related crimes is a growing priority in the United States. The crime gun intelligence (CGI) framework, centered on evidence-based approaches, is a key approach to accomplish this. This article explores the relative contributions of various evidence types to case clearance. We examine gun-related crimes investigated by the Manchester Police Department (MPD) in New Hampshire from 2017 to 2022 to see how the use of NIBIN, e-Trace, firearm recovery, physical evidence, social media, and video evidence impacted the likelihood of arrest. Results suggest that recovering firearms and having video evidence are key elements for increasing the likelihood of an arrest. CGI-related evidence and other evidence types were typically predicted to have no significant effects. NIBIN and physical evidence were associated with negative effects on arrest in some instances. The practical implications of these findings, as well as their limitations and directions for future research, will also be discussed.

Predicting Short Time-to-Crime Guns: a Machine Learning Analysis of California Transaction Records (2010–2021)

Gun-related crime continues to be an urgent public health and safety problem in cities across the US. A key question is: how are firearms diverted from the legal retail market into the hands of gun offenders? With close to 8 million legal firearm transaction records in California (2010–2020) linked to over 380,000 records of recovered crime guns (2010–2021), we employ supervised machine learning to predict which firearms are used in crimes shortly after purchase. Specifically, using random forest (RF) with stratified under-sampling, we predict any crime gun recovery within a year (0.2% of transactions) and violent crime gun recovery within a year (0.03% of transactions). We also identify the purchaser, firearm, and dealer characteristics most predictive of this short time-to-crime gun recovery using SHapley Additive exPlanations and mean decrease in accuracy variable importance measures. Overall, our models show good discrimination, and we are able to identify firearms at extreme risk for diversion into criminal hands. The test set AUC is 0.85 for both models. For the model predicting any recovery, a default threshold of 0.50 results in a sensitivity of 0.63 and a specificity of 0.88. Among transactions identified as extremely risky, e.g., transactions with a score of 0.98 and above, 74% (35/47 in the test data) are recovered within a year. The most important predictive features include purchaser age and caliber size. This study suggests the potential utility of transaction records combined with machine learning to identify firearms at the highest risk for diversion and criminal use soon after purchase.

Quasi-experimental study finding no localised gun crime or call reduction after gun buybacks in Philadelphia

IntroductionGun buyback programmes have been popular in the USA since the 1970s. Studies show that they have no effect on citywide gun crime rates, but more microlevel examinations around gun...

Suspicious Activity Detection Using Different Models

Abstract: In today's insecure world, video surveillance systems play a significant role in keeping both indoors and outdoors secure. Real-time applications can utilize video surveillance components, such as behavior recognition, understanding and classifying activities as normal or suspicious. People are at risk from suspicious activities when it comes to the potential danger they pose. Detecting criminal activities in urban and suburban areas is necessary to minimize such incidents as criminal activity increases. The early days of surveillance were carried out manually by humans and involved a lot of fatigue, since suspicious activities were rare compared to everyday activities. Various surveillance approaches were introduced with the advent of intelligent surveillance systems. This paper analyzes two cases that could pose a threat to human lives if ignored, namely the detection of gun-related crimes, the detection of abandoned luggage, the detection of human violence, the detection of lock hammering, the theft of wallets, and the tempering of ATMs on surveillance video frames. In these papers they have used a neural network model that is Faster R-CNN and YOLOv3 technique to detect these activities.

Blockchain Use Case in Ballistics and Crime Gun Tracing and Intelligence: Toward Overcoming Gun Violence

In the United States and around the world, gun violence has become a long-standing public safety concern and a security threat, due to violent gun-related crimes, injuries, and fatalities. Although legislators and lawmakers have attempted to mitigate its threats through legislation, research on gun violence confirms the need for a comprehensive approach to gun violence prevention. This entails addressing the problem in as many ways as possible, such as through legislation, new technological advancements, re-engineering supply, and administrative protocols, among others. The research focuses on the technological, supply, and administrative aspects, in which we propose a manner of managing gun-related data efficiently from the point of manufacture/sale, as well as at points of transfers between secondary sellers for the improvement of criminal investigation processes. Making data more readily available with greater integrity will facilitate successful investigations and prosecutions of gun crimes. Currently, there is no single and uniform platform for firearm manufacturers, dealers, and other stakeholders involved in firearm sales, dissemination, management, and investigation. With the help of Blockchain technology, gun registry, ownership, transfers, and, most importantly, investigations, when crimes occur, can all be managed efficiently, breaking the cycle of gun violence. The identification of guns, gun tracing, and identification of gun owners/possessors rely on accuracy, integrity, and consistency in related systems to influence gun crime investigation processes. Blockchain technology, which uses a consensus-based approach to improve processes and transactions, is demonstrated in this study as a way to enhance these procedures. To the best of our knowledge, this is the first study to explore and demonstrate the utility of Blockchain for gun-related criminal investigations using a design science approach.

Suspicious Activity Detection

Abstract: In today's insecure world, video surveillance systems play a significant role in keeping both indoors and outdoors secure. Real-time applications can utilize video surveillance components, such as behavior recognition, understanding and classifying activities as normal or suspicious. People are at risk from suspicious activities when it comes to the potential danger they pose. Detecting criminal activities in urban and suburban areas is necessary to minimize such incidents as criminal activity increases. The early days of surveillance were carried out manually by humans and involved a lot of fatigue, since suspicious activities were rare compared to everyday activities. Various surveillance approaches were introduced with the advent of intelligent surveillance systems. This paper analyzes two cases that could pose a threat to human lives if ignored, namely the detection of gun-related crimes, the detection of abandoned luggage, the detection of human violence, the detection of lock hammering, the theft of wallets, and the tempering of ATMs on surveillance video frames. In these papers they have used a neural network model that is Faster R-CNN and YOLOv3 technique to detect these activities.

“I Know a Guy and He’s Got Guns Galore”: Accessing Crime Guns in the Australian Illicit Firearms Market

ABSTRACT Despite there being a highly regulated firearms market, Australian criminals continue to have significant access to illicit firearms. This paper focuses specifically on the role of brokers in the illicit firearms market. It draws from 75 in-depth interviews with prisoners convicted of serious gun-related crimes in Australia. We note how these actors occupy the margins of our interview data yet are seemingly central to the supply and circulation of firearms. Six main means of illicit firearm acquisition are identified, ranging from supply through family members to being vouched for by a known person who provides a bridge to the appropriate supplier (or ‘guy’). The role of straw purchasers, theft, and/or manufacturing in the illicit firearm trade are also explored. We conclude with a provisional profile of the ‘middleman’ and comment on the resilience of the underworld code and its protection of key actors in gun crime milieux as well as implications for prevention and law enforcement.

Research Progress on Touch DNA on Cartridge Cases in Forensic Field

Cartridge cases are crucial physical evidence in gun-related crimes. The successful identification of the touch DNA on cartridge cases can help to screen the suspects and reconstruct the gun-related crime scene. With the improvement of DNA extraction methods and the sensitivity of amplification kit, forensic examiners are expected to obtain more valuable information by testing the touch DNA on cartridge cases. In practical cases, the touch DNA detection on cartridge cases often encounters with low DNA content degradation, mixing and the gunshot residual interference, which brings more challenges to DNA examination and identification. This article reviews forensic research of touch DNA on the cartridge cases from the aspects of factors affecting touch DNA on cartridge cases, advances in the extraction and amplification methods, and the practical applications in order to provide reference for forensic identification of touch DNA on the cartridge cases in real cases.

A distant relationship?\u2014investigation of correlations between DNA isolated from backspatter traces recovered from firearms, wound profile characteristics, and shooting distance

In molecular ballistics, where traces originating from the use of firearms against biological targets are investigated, “backspatter” traces are of particular importance. This biological material comprising blood and tissue from the victim is propelled back from the bullet entry site towards the direction of the shooter and can consolidate and persist on the inner and outer surfaces of the firearm, from where it can be collected and analyzed. Thus, a connection between the weapon and the victim can be established solely by molecular biological trace analysis. For the criminalistic investigation of gun-related crimes, the determination of the distance between the weapon and the victim can be of critical importance in reconstructing the circumstances of a crime. In this study, we investigated possible correlations between the shooting distance and the amount of backspatter in/on the used firearm. To this purpose, we employed a previously established skull model and performed shootings in triplicates from various distances up to 50 cm with two types of handguns (pistol and revolver). Backspatter was collected from various sampling locations, and DNA contents were quantified. A post-shooting wound channel evaluation was conducted by optical and radiological evaluation. The obtained DNA yields varied considerably between replicates from the same and from different distances. In contrast, apart from contact shots, no meaningful differences were observable in wound channel evaluations. In summary, no meaningful correlation between backspatter distribution and DNA yields, the shooting distance and the condition of the wound channel could be established.

DNA transfer to firearms in alternative realistic handling scenarios

Firearms are the most relevant items of evidence in gun-related crimes, likely bearing various traces facilitating an objective reconstruction of the crime. Trace DNA recovered from firearm surfaces might help to identify individual(s) having handled the firearm and thereby possibly to link the firearm and the corresponding shooter, however, the interpretation of DNA traces on handled items can be challenging and requires a detailed understanding of various factors impacting DNA prevalence, transfer, persistence and recovery. Herein, we aimed at improving our understanding of factors affecting the variability of trace DNA characteristics recovered from firearms handled in gun-related crimes: Skin contact traces were recovered from various outer surfaces of two types of firearms handled in four realistic, casework-relevant handling scenarios and the corresponding trace characteristics (DNA yield, number of contributors, relative profile contribution for known and unknown contributors, LRs) were compared. Trace DNA characteristics differed distinctly between handling conditions, firearm and surface types as well as handling individuals and intraindividual deposits emphasizing the variability and complexity of trace DNA profile composition expected to be recovered from firearms after realistic handling scenarios. The obtained results can provide useful insights for forensic experts evaluating alternative activity level propositions in gun-related crimes.

Patterns of adolescent gun carrying and gun-related crime arrests in Indianapolis, Indiana over an 11-year time period

Adolescent males are disproportionately affected by homicide as both victims and offenders. Indianapolis has seen increases in youth homicides over the past few years; gun carrying increases an individual's risk for involvement in firearm violence. It is unclear how often youth are arrested for gun carrying and gun-related crimes. Examining these patterns may identify an opportunity for intervention. This study is a descriptive epidemiology analysis that examines patterns of gun carrying and gun-related crime arrests among justice involved youth in Marion County (Indianapolis), Indiana. We accessed juvenile court records from January 1, 2006 to December 31, 2016 on all individuals arrested for a gun carrying offense (i.e., illegal possession of a firearm or gun; n = 711) and all individuals arrested for a gun-related crime (i.e., homicide, robbery, aggravated assault; n = 150). Data were analyzed in fall 2019. Proportions of juvenile arrests for both gun carrying (47.0 per 1000 arrests) and gun-related crime (25.4 per 1000 arrests) have substantially increased compared to ten-years ago (4.5 per 1000 arrests and 2.0 per 1000 arrests, respectively). Of those arrested, 27.7 per 100,000 population were arrested for a repeated gun-related offense; of which 21.5 per 100,000 were first arrested for gun carrying and 6.2 per 100,000 were arrested for a gun-related crime. The majority of gun-related repeat offenders were first arrested for gun carrying; therefore, these gun-carrying arrests may be an opportunity to intervene on an individual level by providing treatment, other needed resources, and discussing safe firearm storage with families and communities.

Smoking Gun? Linking Gun Ownership to Crime Victimization and Neighborhood Crime

Using linked individual data on concealed handgun permits (CHP), reported crimes and arrests, I examine the dynamics of gun-ownership, victimization and neighborhood crime. I estimate the impact of guns on crime through a shift-share instrument based on spikes in gun sales after high-profile events that impact beliefs about future gun rights and existing variation in a neighborhood's share of likely future gun-owners (republicans). Results show a 5.9% increase in neighborhood crime for each additional CHP issued with gun-related crimes suggesting a role for guns stolen and moved to the illegal gun market, and increased use of guns for violent crimes.

Firearms and Injuries during Home Robberies in Mexico, 2010–2017

According to data from Mexico’s National Crime Victimization and Public Security Surveys (ENVIPE), from 2010 through 2017, home robberies involving an interaction between a victim and an aggressor occurred every two minutes and resulted in more than 257,000 injuries. The objective of this study is to explore whether victims of home robberies in Mexico are more likely to report an injury if perpetrators are armed with a gun. This analysis compiles data from ENVIPE and runs a binary logistic regression. In contrast to literature on robberies in the United States and studies on street robberies in Mexico, results show that when perpetrators are armed with guns, victims of home robberies in Mexico are more likely to report an injury, even though these injuries are rarely caused by a gunshot. These discrepancies may be explained by different factors. Unlike in the United States, most gun-related crimes in Mexico are perpetrated by organized criminal groups that obtain firearms through illegal channels. Members of these groups are prepared to engage on physical violence against their victims. Additionally, unlike street robberies, the enclosed setting of home robberies might facilitate the use of physical violence as a strategy to coerce victims and successfully obtain profits without generating public attention. Overall, perpetrators use guns as a tool to exert control and avoid resistance. These findings suggest that policies to address organized crime and halt easy access to guns should be prioritized on Mexico’s national security agenda.

More guns, less crime? A dynamical systems approach

The laws regulating the ownership and use of firearms by civilians have been debated in several countries. The debate arises because the relations among firearm accessibility, right to self-defense, firearm-related mortality, and violent crime statistics can suggest divergent strategies to combat criminality. Here, a model written in terms of differential equations is proposed to answer the question: do more legal guns mean less crime committed by illegal guns? From this model, the impact of distinct gun-control policies on the rate of gun-related crimes is investigated. It is analytically shown that strong gun-control leads to the minimum number of illegal guns; however, this policy does not assure a crime-free society. Weak gun-control can lead to a crime-free society; however, this policy requires the maximum number of legal guns in the hands of the civil society.

Analysis of DNA transfer to firearms considering relevant alternative handling scenarios

The presented study aims at gaining a better understanding of factors affecting the variability of trace DNA profiles obtained from biological material recovered from firearms handled in gun-related crimes. For this purpose, skin contact traces resulting from four realistic alternative handling scenarios were recovered from different surfaces of two types of firearms and the corresponding trace profile characteristics (DNA yield, relative profile contribution for known and unknown contributors) were compared. Observed differences between handling conditions, firearms and surface types, handling individuals and individual deposits emphasize the complexity of trace DNA profile composition expected to be recovered from firearms after realistic handling scenarios. The obtained data will serve as useful information for forensic scientists providing expert opinion on alternative propositions at activity level in the context of gun-related crimes.

First insights into the correlation of DNA quantity isolated from backspatter traces in firearms and the shooting distance

In molecular ballistics, the molecular genetic analysis of biological material is integrated with the biophysical wounding events and trace investigations of terminal ballistics. It aims to support the objective, evidence-based reconstruction of gun-related crimes. Of central interest is the analysis of backspatter traces: biological material propelled back from the entry site of a bullet after impact on a biological target. This study is a first approach to systematically investigate possible correlations or patterns between the amount of recoverable DNA (yield) from backspatter traces found on and inside fired guns and the shooting distance. After firing shots from five distances (0, 5, 10, 15, 30 cm) with both a pistol and revolver in triplicates, no clear correlations or patterns can be observed, due to considerable variation between measurements from identical triplicates and a lack of linear relation between distance and yield, e.g. yields from even 30 cm shots will sometimes exceed those of contact shots. Wound channel evaluation was performed as well and distinct differences between contact shots and distance shots could be observed, but not between any distant shots.

GIS Crime Mapping to Support Evidence-Based Solutions Provided by Community-Based Organizations

This study explored geospatial technologies to support efforts of community organizations and of the Chicago Gun Violence Research Collaboration to reduce gun-related crimes. It entailed (1) identification of spatial trends in gun-related crimes during 2012 to 2017 in each of the following four areas: Austin, East Garfield, North Lawndale, and Englewood; (2) investigation of changes in crime patterns near safe school zones in the areas before and after the establishment of the city’s safe passage routes in 2009 to protect the youth from street violence when traveling to school; and (3) development of a web-enabled mobile application to provide researchers and residents with spatial information on local crime incidents and to enable community members to collect and share their information in a GIS environment. The results of this research revealed that, although the number of safe passage routes has increased in these areas over the past several years, hotspot trends for gun-related crimes have intensified in most of the communities in these areas, which include school zones and safe passage routes. Accordingly, it turned out that GIS can serve as an ideal platform supporting collaborative efforts between communities and researchers.

Evaluating Project Safe Neighborhoods in Connecticut: a Youth Opportunity Initiative

Despite containing numerous wealthy geographic areas, the state of Connecticut continues to struggle with social and economic distress, along with gun-related crime. Problem analysis in urban areas revealed a critical need for services aimed at deterring violent and gun-related crime in two target populations: serious juvenile offenders, aged 14–17 years, and at-risk youth, aged 11–13 years. Using a quasi-experimental design, this study aimed to evaluate the effect of Project Safe Neighborhoods (PSN) on youth in two cities in Connecticut. Implementation resulted in 133 young people receiving a variety of services in New Haven and Bridgeport. Evaluation research assessed intervention efforts designed to (1) build on the strengths and address the challenges of each juvenile offender, (2) expand community outreach and education efforts to reinforce and reward positive attitudes and behaviors surrounding “no-gun policies,” and (3) utilize data-driven decision-making to guide program implementation and evaluate the results. Our findings suggest that youth who participated in Connecticut’s PSN Youth initiative benefited from the services provided and exhibited a decreased involvement in the juvenile justice system following enrollment.

Gun-Related Crime in Detroit, Michigan: Exploring the Spatial Context of Licensed Firearm Availability and Neighborhood Characteristics

The linkage between firearms and violent crime has been documented in several criminological research efforts, with different conclusions. This study explores the relationship between gun availability and gun-related violent crimes, using the city of Detroit, Michigan, as a case study. Based on the primary role of federal firearm licensees (FFLs) as a spigot for the flow of firearms into communities, spatial accessibility to FFL locations is used as a measure of gun availability. Global regression models are used to investigate the association between gun-related crime rates and spatial accessibility to FFL locations. Geographically weighted regression (GWR) is also employed to assess such spatially varying accessibility across the study area. In the global models, gun availability and selected population variables explained up to 46 percent of the variation in crime rates. The GWR model explained 59 percent of the variation in crime rates. The analysis shows a global significant positive effect of gun availability on gun-related crime rates, with strong spatial variability across the study area. The results suggest a significant linkage between gun-crime rates and spatial accessibility to FFL in the study area. Based on the findings, the location and activities of FFL dealers might be a contributing factor to the rates of gun-related crimes.

Evaluating polar and non-polar solvents extraction efficiency of gunpowder components by FTIR

Introduction: Crimes involving firearms have been increasing and is a current transnational concern. To face such issues the development of analytical procedures is paramount to increase the efficacy of criminal investigation on homicides and other gun related crimes. The identification of an ammunition type or brand from a simple residue would represent a major contribution for gunshot residues analysis. Such a breakthrough will benefit homicides and war crimes investigation. The composition of gunpowder varies and each ammunition type contains a given formula and often specific components [1–3] suggesting that Fourier-transform infrared spectroscopy (FTIR) might be a useful technique for the rapid analysis of gunpowders [2]. Indeed, FTIR has an outstanding discriminatory ability when coupled with chemometrics analysis [3]. Here we present the optimization of the extraction organic solvent for analysis of ammunition contents by FTIR which is an essential step for the discriminatory study of ammunition brands. Materials and methods: An ammunition of caliber .22RL was purchased at Soldiers®. The sample was dissolved in eight different solvents (Acetone, Acetonitrile, Dichloromethane (DCM), Ethanol, Isooctane, Methanol, Methyl Ethyl ketone and n-Hexane), subjected to ultrasound for 30 min and followed by centrifugation. The supernatant was collected and analyzed on a Perkin Elmer 65 FTIR spectrometer coupled to an ATR accessory. A spectral window of 4000-525 cm−1 was used and 32 scans were accumulated at 1cm−1 resolution. Results: Figure 1 shows the FTIR spectra of methanol and n-hexane for the sample used. From the spectra it is clear that methanol is a better extractor than n-hexane. Of the eight solvents used, methyl ethyl ketone, acetone and methanol had the better extraction efficiency of gunpowder (GP) while n-hexane and dichloromethane were not able to extract GP. Figure 1. FTIR spectra of sample E dissolved in methanol (blue) and n-Hexane (red). Discussion and conclusions: This study showed that the best solvents for extraction of GP are the more polar solvents containing carbonyl (C = O) and hydroxyl (OH) groups. The best extraction solvents were Methyl ethyl ketone and acetone followed by methanol.