Psychological markers underlying murder weapon profile: a quantitative study

Area of Science:

• Criminology
• Forensic Psychology
• Behavioral Science

Background:

• Weapon usage is critical in murder investigations, yet psychological factors influencing choices remain under-researched.
• Existing studies focus on environmental, demographic, and availability factors, neglecting the perpetrator's psychological profile.

Purpose of the Study:

• To investigate the influence of psychological traits on weapon selection among male murderers.
• To bridge the gap in understanding the psychological underpinnings of weapon usage in criminal behavior.

Main Methods:

• Cross-sectional study of 71 male murderers in 11 Malaysian prisons.
• Utilized a guided self-administered questionnaire with sociodemographic data and validated psychometric instruments.
• Employed independent sample t-tests, Kruskal-Wallis tests, and one-way ANOVA to analyze psychological trait differences related to weapon usage.

Main Results:

• Specific psychological traits were found to significantly influence the number, source, and type of weapons used.
• Differences in psychological profiles were observed between murderers using single versus multiple weapons.
• Variations in psychological traits correlated with different weapon sources.

Conclusions:

• Psychological functioning is a key determinant in weapon selection during murder.
• Findings offer valuable insights for the psychological profiling of unknown offenders within the Malaysian context.
• Highlights the need for integrating psychological assessments in criminal investigations involving weapon use.