Mass Murder: An Understanding of Its Causes and Prevention


  • Silvio José Lemos Vasconcelos Departamento de Psicologia da Universidade Federal de Santa Maria (UFSM), Santa Maria, RS, Brasil
  • Lisiane dos Santos Welter Departamento de Psicologia da Universidade Federal de Santa Maria (UFSM), Santa Maria, RS, Brasil
  • Thamires Pereira Barbosa Departamento de Psicologia da Universidade Federal de Santa Maria (UFSM), Santa Maria, RS, Brasil
  • Luiza Vieira Macedo Pinto Departamento de Psicologia da Universidade Federal de Santa Maria (UFSM), Santa Maria, RS, Brasil
  • Rafaella Valli Santanna Departamento de Psicologia da Universidade Federal de Santa Maria (UFSM), Santa Maria, RS, Brasil
  • Eduarda Portella Quevedo Departamento de Direito da Universidade Federal de Santa Maria (UFSM), Santa Maria, RS, Brasil
  • Fernanda de Vargas Departamento de Ciências Criminais da PUCRS, Santa Maria, RS, Brasil



Juridical psychology, Mass murder, Mental health.


Mass murder is defined when at least three or four murders occur at the same time and in the same place. Occurrence occurs in a short period of time, within a few hours, and in a single location or in nearby areas, such as work, leisure or school. In Brazil, despite recent episodes, the subject is still little investigated, mainly by psychologists. Brazilian scientific production on mass killings is really scarce. This article aims to elucidate the current state of knowledge on the subject. The authors perform a non-systematic review of epidemiological and social studies on the topic. The occurrence of mass killings can be understood from a biopsychosocial understanding, including psychotic symptoms that drive crime. Issues of prevention on the international stage are also addressed in this article. This study can contribute to boost national scientific production on the subject and generate timely reflections on the prevention of similar problems.


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How to Cite

Lemos Vasconcelos, S. J., dos Santos Welter, L., Pereira Barbosa, T., Macedo Pinto, L. V., Valli Santanna, R., Portella Quevedo, E., & de Vargas, F. (2021). Mass Murder: An Understanding of Its Causes and Prevention. Brazilian Journal of Forensic Sciences, Medical Law and Bioethics, 10(3), 401–422.