Purpose: The aim of this study is to investigate the effectiveness of the violent criminal investigation system used by the Royal Thai Police technology. Theoretical framework: This study explores the effectiveness of the Royal Thai Police's violent criminal investigation system. It uses a theoretical framework that includes criminal investigation theory, criminal behavior analysis, forensic psychology, and police technology. The framework focuses on crime scene analysis, evidence collection, suspect identification, and case management. It also explores criminal behavior analysis, which focuses on understanding offenders' motivations, patterns, and psychological characteristics. Forensic psychology is used to understand the psychological aspects of criminal behavior and its implications for investigative procedures. The study aims to identify strengths and weaknesses, propose improvements, and contribute to the development of more robust investigative practices. ...