The integration of Artificial Intelligence (AI) into criminal justice systems presents a complex landscape of opportunities and challenges. This research article critically examines the ethical implications of AI applications in various facets of criminal justice, from predictive policing to sentencing algorithms. While AI promises enhanced efficiency and data-driven decision-making, it simultaneously raises significant concerns about fairness, transparency, and the preservation of due process rights. This study employs a multidisciplinary approach, combining legal analysis, ethical philosophy, and empirical research to evaluate the current state of AI in criminal justice and project future trajectories. We analyze case studies from multiple jurisdictions, highlighting both successful implementations and controversial failures of AI systems in law enforcement and judicial processes. Our findings reveal a tension between the pursuit of efficiency through AI and the fundamental principles of due process. We identify several key ethical challenges, including algorithmic bias, lack of transparency in decision-making processes, and the potential erosion of human judgment in critical legal determinations. The research also uncovers disparate impacts on marginalized communities, raising concerns about the exacerbation of existing inequalities within the justice system. To address these challenges, we propose a comprehensive ethical framework for the development and deployment of AI in criminal justice. This framework emphasizes the need for continuous human oversight, regular audits of AI systems, and the establishment of clear accountability mechanisms. We argue for a balanced approach that leverages the benefits of AI while safeguarding individual rights and maintaining the integrity of judicial processes. The article concludes by outlining policy recommendations and best practices for lawmakers, judiciary, and law enforcement agencies. These recommendations aim to foster responsible innovation in criminal justice AI, ensuring that technological advancements align with ethical standards and constitutional protections. Our research contributes to the ongoing dialogue on AI ethics in the legal domain and provides a roadmap for the ethical integration of AI in criminal justice systems worldwide.