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Five Things About Protecting Against Mass Attacks

NCJ Number
Date Published
October 2023
2 pages

This fact sheet presents information gleaned from a research project that analyzed evidence and research, leading to the development of the Mass Attacks Defense Toolkit; it provides a link to the Toolkit; and gives an overview of five critical points on defending against mass attacks.


Mass public attacks, whether personally or ideologically motivated, cause much concern and fear. Nonetheless, actions can be taken to prevent, defend against, and respond to mass attacks. This fact sheet discusses five critical points from a recent National Institute of Justice-supported research project that analyzed over 600 mass attack plots, hundreds of articles and resources, and dozens of expert interviews to develop the Mass Attacks Defense Toolkit. In this fact sheet, NIJ discusses the following five things that can be done to protect against mass attacks: 1) We can proactively prevent many mass attacks. Public reporting prevented almost two-thirds of the foiled plots highlighted in the toolkit; 2) Communities need multidisciplinary, multi-partner teams to follow up and assess warning signs and determine what to do next; 3) Adequate preparation reduces casualties in the critical beginning stages of an attack before responders arrive to the scene; 4) An effective joint response to a mass attack requires planning and training that includes everyone who will be involved in a response; 5) The recovery plan must include planning and training for the aftermath.

Date Published: October 1, 2023