An authoritative review of foundational research in criminal justice. Forty Studies that Changed Criminal Justice, 2e presents a thorough yet concise summary of the major and influential research studies in the field of criminal justice. Knowledge in criminal justice is developed with research, yet introductory textbooks fail to offer more than cursory synopses of the significant empirical studies that established the foundation of the discipline. This book provides a rich understanding of important research published in each of the three general areas of criminal justice: policing, courts, and corrections. More than a just collection of original published articles, the text is a summary of studies that have shaped the criminal justice system.