By John S. Hollywood, Keith Gierlack, Pauline Moore, Thomas Goode, Henry H. Willis, Devon Hill, Rahim Ali, Annie Brothers, Ryan Bauer, Jonathan Tran

Attacks on soft targets and crowded places (ST-CPs) represent a significant challenge. The U.S. Department of Homeland Security requires research and development to assess methods for reducing the propensity and loss of life from these types of attacks. In response, researchers from the Homeland Security Operational Analysis Center conducted a comprehensive landscape assessment of the threat to ST-CPs and corresponding security measures. This assessment integrated literature reviews, attack plot analyses, grant data reviews, and security cost modeling to identify both needs for improvement and recommended research and investment priorities for addressing those needs.

The number of attack plots is broadly aligned with regional population counts. The most-common motivations for ST-CP attacks have been personal, followed by terrorist and extremist motivations. Education and private buildings (workplaces) are the most–frequently targeted types of ST-CPs. Attacks on ST-CPs that have large, accessible crowds, such as houses of worship, shopping malls, restaurants, bars, and nightclubs, had the highest average lethality.

To defend ST-CPs, a layered approach has security measures work together to improve the chance that an attack will be stopped or mitigated. Prevention measures stop attacks before they reach execution; however, the public needs to know what warning signs to look for and how to report them, and threat assessment teams need to assess tips and follow up appropriately. Access control systems, such as locks, secured windows, and secured entryways, have been effective and efficient. Bystanders and security have both stopped attacks; groups of bystanders tackling shooters have been highly effective.

Key Findings

The conditions that a would-be attacker must fulfill to successfully execute a high-fatality attack are collectively the attack chain; interrupting that chain can prevent or reduce casualties

• An attacker must carry out many steps to complete a high-fatality attack. The attacker must become fully committed, plan, acquire weapons and skills, and make other preparations without being detected and reported by others. Once on scene, the attacker must get through the site's security layers and engage a crowd without being stopped quickly.

• A system-based, or layered, approach helps security measures work together to improve the chances that an attack will be stopped or mitigated at any of these steps, guarding against single points of failure.

• Prevention measures are perhaps the most-important factors in interrupting the attack chain because they can and have halted many plots before they reached execution. Reports of warning signs have been key. However, the public must know what to look for and how, and authorities need threat assessment teams and training to assess tips and follow up appropriately.

• Access and entry-control systems, including locks, secured windows, and secured entry spaces, have been effective and efficient in protecting against attackers.

• Both bystanders and on-scene security have been effective in stopping attacks. Groups of bystanders tackling shooters have been highly effective in ending attacks.

  Recommendations

• Seek methods for deterring and dissuading would-be attackers from becoming committed to plots.

• Develop indicators and training to detect suspicious seeking of weapons and ammunition.

• Develop enhancements to "see something, say something" campaigns.

• Develop and evaluate campaigns to reduce hoax threats of violence.

• Develop rules and processes for assessment, monitoring, and follow-up with reported threats, including processes for initial wellness checks.

• Evaluate the effectiveness of site security technologies in stopping simulated attacks.

• Study the social costs of security measures more.

• Develop a model strategy for open and nonsecure spaces, such as parks, parking lots, shopping malls, and restaurants.

• Improve command and control, leadership, and coordination during attack responses.

• Study alternatives to traditional voice radio communications during attack responses.

• Continuously track and analyze mass-attack plots.

• Determine whether some ordinary criminal shootings should be treated as mass attacks on ST-CPs.

• Seek ways to reduce the mass psychological impacts of attacks.

• Support detailed tracking of grant spending related to ST-CP security.

• Fund enhanced public education and training on what to report and how and on how to respond to an active attacker.

• Provide funding to cross-organizational threat assessment teams, security teams, and managers, and provide training on how to report on and how to respond during an incident.

• Fund access control systems.

• Fund medical supplies and training to match updated medical standards.

Santa Monica, CA: RAND, 2024. 168p.

By David Weisburd, Cody W. Telep , Heather Vovak , Taryn Zastrowa , Anthony A. Braga , and Brandon Turchan  

  Can police be trained to treat people in fair and respectful ways, and if so, will this influence evaluations of the police and crime? To answer these questions, we randomly allocated 120 crime hot spots to a procedural justice (PJ) and standard condition (SC) in three cities. Twenty-eight officers were randomly assigned to the conditions. The PJ condition officers received an intensive 5-d training course in the components of PJ (giving voice, showing neutrality, treating people with respect, and evidencing trustworthy motives). We used police self-report surveys to assess whether the training influenced attitudes, systematic social observations to examine impacts on police behavior in the field, and arrests to assess law enforcement actions. We conducted pre and post household surveys to assess resident attitudes toward the police. Impacts on crime were measured using crime incident and citizen-initiated crime call data. The training led to increased knowledge about PJ and more procedurally just behavior in the field as compared with the SC condition. At the same time, PJ officers made many fewer arrests than SC officers. Residents of the PJ hot spots were significantly less likely to perceive police as harassing or using unnecessary force, though we did not find significant differences between the PJ and SC hot spots in perceptions of PJ and police legitimacy. We found a significant relative 14% decline in crime incidents in the PJ hot spots during the experiment.  

Missouri: PNAS, 2022. 6p.

By  Kate Bowers , Lisa Tompson and Shane D. Johnson

In many disciplines, there is a wealth of primary evaluation research on what works, and systematic reviews that synthesize that evidence. This is, of course, extremely positive. However, the sheer scale of the information and the way in which it is indexed and presented can mean that it is difficult for practitioners to locate the best available evidence. For this reason, in health, education, and other disciplines, using techniques from information science, researchers have systematically assembled databases such as those hosted on healthevidence.org and educationendowmentfoundation.org which bring together the most reliable evidence. Hitherto, no such database has existed for crime and criminal justice interventions. This article sets out some of the challenges and early findings of one exercise which aims to produce such a database, being completed as part of the What Works Centre for Crime Reduction initiative in collaboration with the College of Policing. 

Policing: A Journal of Policy and Practice, Volume 17, 2023

By David Weisburd George Mason University, Hebrew University Taryn Zastrow

Recent data in New York City suggest that violent crime is on the rise. However, over the last three decades, there has been a more than 70% decline in index crimes as reported by the FBI. This led to a growing perception, especially among critics of policing, that crime in NYC had become a marginal problem, or at least that it had declined to levels such that there was no need to place too much emphasis on crime control. Combined with concerns about police abuses and claims of disparities in policing in minority and disadvantaged communities, this fueled calls for defunding the police. In this report, we focus on the high-crime hot spots where 25% and 50% of NYC crimes were committed. The crime numbers on those streets suggest that, despite the encouraging overall crime decline over the past few decades, many city streets continue to have very high crime levels that need to be addressed by police and other agents of the city government. Our report looks beyond general crime statistics to the hot spots of crime where much crime in a city is concentrated. Looking at NYPD crime reports for 2010, 2015, and 2020, we find that about 1% of streets in NYC produce about 25% of crime, and about 5% of streets produce about 50% of crime. This is consistent across the three years, showing that a very small proportion of streets in the city are responsible for a significant proportion of the crime problem. Mapping crime in NYC, we found that high-crime streets are spread throughout the city, though concentrated in Manhattan, the Bronx, and Brooklyn. In turn, we observed a good deal of street-by-street variability, with the highest-crime streets often adjacent to streets with little or no crime. This means that it is misleading to classify whole neighborhoods as crime hot spots, since the majority of streets—even in higher-crime areas—are not. This is an important lesson for police and ordinary citizens who mistakenly see very large areas as crime-ridden. We also found a good deal of stability in the locations of crime hot spots. Nearly all the streets that were hot spots as we have defined them in 2010 were also hot spots in 2020.

New York: Manhattan Institute, 202. 30p.

By Geoffrey C. Barnes, Simon Williams | Lawrence W. Sherman | Jesse Parmar | Paul House | Stephen A. Brown

In this article, we examine how communities can maximize deterrence of crime while minimizing cost and police intrusion on public life. Using 3,720 hot spot-days, we show that the “sweet spot” duration of police absence, to maximize the residual deterrence of crime, was a full four days after the last day of targeting police patrol at each hot spot. Over a 248-day period, we randomly reshuffled 15 separate hot spots daily into either treatment (targeted police patrols) or control (no targeted patrols) for that day, so that all locations repeatedly switched between randomly assigned groups. This repeated crossover design (Cochrane & Cox, 1957; Fienberg et al., 1980) included random periods of up to 20 consecutive days in which individual hot spots remained in the control condition, allowing us to measure how soon, and by what trajectory, the residual deterrent effect of targeted patrolling wore off. After four days without patrolling, there was a sudden termination of residual deterrence, marked by a 66% rise in offense frequency, and a 395% spike in our index of crime harm (House & Neyroud 2018), compared to the treatment condition. It may be possible to deploy less, not more policing and still maximize deterrent effects.

Sweet Spots Pre-Print 2020-07

By The U.S. Department of Homeland Security (DHS)

This document was developed through efforts by the U.S. Department of Homeland Security’s (DHS) Homeland Security Advisory Council (HSAC or Council) Intelligence and Information Sharing Working Group, to develop guidelines for local and state agencies in relation to the collection, analysis, and dissemination of terrorism-related intelligence (i.e., the fusion process). Those efforts laid the foundation for the expansion of the Fusion Center Guidelines to integrate the public safety and private sector entities. The guidelines are intended to ensure that fusion centers are established and operated consistently, with enhanced coordination efforts, strengthened partnerships, and improved crime-fighting and antiterrorism capabilities. Key elements include: sector-specific information and sharing plans; identification of goals for the fusion center; creation of a representative governance structure and collaborative environment for intelligence sharing among local, state, tribal, and federal law enforcement agencies, public safety agencies, and the private sector; utilization of memoranda of understanding (MOUs), non-disclosure agreements (NDAs), and other agency agreements, as appropriate; leveraging of databases, systems, and networks to maximize information sharing; creating environments that promote communication among entities; development and publication of privacy and civil liberties policies; ensuring appropriate security measures for the facility, data, and personnel; integration of technology, systems, and people; achievement of a diversified representation of personnel based on the needs and functions of the center; ensuring adequate personnel training; provision of multitiered educational program for intelligence-led policing and information sharing; offering a variety of intelligence services and products to customers; developing and adhering to a policies and procedures manual; defining expectations and performance measurement for determining effectiveness; establishing and maintaining the center based on funding availability and sustainability; and the development and implementation of a communications plan among personnel, officers, and the general public. The eighteen guidelines provided reflect those key concepts; the document includes eight appendices.

Washington, DC: DHS, 2023. 104p..

By Peter Manning

With the rise of surveillance technology in the last decade, police departments now have an array of sophisticated tools for tracking, monitoring, even predicting crime patterns. In particular crime mapping, a technique used by the police to monitor crime by the neighborhoods in their geographic regions, has become a regular and relied-upon feature of policing. Many claim that these technological developments played a role in the crime drop of the 1990s, and yet no study of these techniques and their relationship to everyday police work has been made available. Noted scholar Peter K. Manning spent six years observing three American police departments and two British constabularies in order to determine what effects these kinds of analytic tools have had on modern police management and practices. While modern technology allows the police to combat crime in sophisticated, detail-oriented ways, Manning discovers that police strategies and tactics have not been altogether transformed as perhaps would be expected. In The Technology of Policing, Manning untangles the varying kinds of complex crime-control rhetoric that underlie much of today's police department discussion and management, and provides valuable insight into which are the most effective—and which may be harmful--in successfully tracking criminal behavior.

New York: New York University Press, 2011. 338p.