Bias in Assessing Decision-making Capacity in Patients with Serious Mental Illness in Hospital Settings

Decision-making capacity (DMC) is a core element of ethical and effective clinical care, ensuring that patients can understand, appreciate, reason through, and communicate informed choices about treatment. Accurate assessment of DMC is essential in psychiatric settings, where serious mental illness (SMI) may affect cognition, insight, or judgment, yet does not inherently imply incapacity. This paper examines how implicit, racial, and cognitive biases can influence DMC evaluations and contribute to disparities, particularly for Black and Hispanic patients with SMI. Diagnostic overshadowing, assumptions about insight, and misinterpretation of culturally influenced communication may lead to incorrect determinations of incapacity and undermine patient autonomy. Evidence indicates that while cognitive impairment is a significant contributor to reduced DMC, many individuals with SMI retain the ability to make reasoned treatment decisions. Standardized tools-such as the MacArthur Competence Assessment Tool and related instruments-can improve reliability and mitigate subjective judgment, though current measures lack explicit integration of cultural and racial considerations. This paper highlights strategies to reduce bias in DMC assessments, including clinician education, development of culturally informed protocols, interdisciplinary decision-making, and expanded access to advocacy resources. These efforts support equitable, accurate, and ethically grounded evaluation of patient capacity across diverse clinical populations.