Therapeutic privilege (TP) is a defence that may be available to doctors who fail to disclose to the patient relevant information when seeking informed consent for treatment if they have a reasonable belief that providing that information would likely cause the patient concerned serious physical or mental harm. In a landmark judgement, the Singapore Court of Appeal introduced a novel interpretation of TP, identifying circumstances in which it might be used with patients who did not strictly lack capacity but might be inclined to refuse recommended treatments. In this paper, we explore the conceptual and practical challenges of this novel interpretation of TP. We propose that more emphasis should be placed on forms of shared and supported decision-making that foster the autonomy of patients with compromised mental capacity while being mindful of the need to safeguard their well-being. The kind of privilege that doctors might need to invoke is one of time and supportive expertise to ensure a flexible, responsive approach calibrated to the individual patients’ needs. The provision of such service would extinguish the need for the novel TP proposed by the Singapore Court of Appeal.