This report delves into the crucial role of statistical data in shaping and supporting criminal justice policy within the United States. It examines the influence of mandatory arrest policies, particularly in domestic violence cases, analyzing their effectiveness and impact on arrest rates. The report also explores the forensic utilization of statistical data, focusing on fingerprint analysis and the importance of minimizing errors through quality control measures. Furthermore, it highlights the significance of policy analysis in assessing the impact of procedural changes within the criminal justice system. The conclusion emphasizes the need for continuous efforts to improve criminal statistics and policy development, aiming to provide better justice for victims and their families, while also deterring offenders and reducing overall crime rates. The report references several academic sources to support its analysis and findings.