"Informed consent" implicitly links the transmission of information to the granting of permission on the part of patients, tissue donors, and research subjects. But what of the corollary, informed refusal? Drawing together insights from three moments of refusal, this article explores the rights and obligations of biological citizenship from the vantage point of biodefectors—those who attempt to resist technoscientific conscription. Taken together, the cases expose the limits of individual autonomy as one of the bedrocks of bioethics and suggest the need for a justice-oriented approach to science, medicine, and technology that reclaims the epistemological and political value of refusal.