Results suggest that decisionmaking is a critical dimension throughout the medical and criminal justice systems, not just at a few select points where key personnel have the ability to exercise considerable discretion; an understanding of that fact requires recognizing the role of systems in affecting decisionmaking. Larger case loads can increase the likelihood that different types of cognitive errors occur, accumulating with or amplifying the effects of one another and potentially causing ripple effects that ultimately lead to inefficiencies and poor outcomes. The article discusses parallels between the medical and criminal justice systems and why comparisons of the two are instructive. In doing so, it emphasizes that the focus on decisionmaking, not the application of a medical model to criminal justice. The article then examines and illustrates specific decisionmaking errors and emphasizes the particular salience of system-level considerations to understanding the causes and impacts of such errors. Drawing on these discussions, the article explores at length their implications for criminal justice practice and policy, in particular, the lessons for criminal justice policymakers, officials, practitioners, and researchers. Notes and references