Informed consent is both a model of medical care and decision making that emphasizes patient autonomy, self-determination and integrity, and legal doctrine, characterized by medical providers’ obligation to offer all of the known information regarding the benefits and risks of medical treatments. Yet, there is a considerable amount of ambiguity in some areas of medical jurisprudence and practice related to informed consent. This becomes apparent in ‘competence’ assessments, or those moments when providers must evaluate whether or not a patient is even capable of offering consent. Using observations at transgender-specific healthcare conferences, I examine how providers describe being tasked with assessing the competence of their transgender patients within an informed consent model. In the process of evaluating trans patients’ capacity for consent, providers become legal proxies and, therefore, authorized to make medical decisions on behalf of their patients. Consequently, how informed consent is understood by providers of trans medicine remains ensnared in a traditional ‘doctor knows best’ model of medicine, rather than a shared decision making process.