Background <p>The aim of this paper is to explore harms to health and dignity generated through stigma from the perspective of people detained in police custody, a neglected population in healthcare research. We adopt an original theoretical approach, bringing together a human rights lens to health, stigma, and the Inverse Care Law (ICL) to show how stigma contributes to the degradation of dignity and poor experiences of <i>quality</i> care within custody.</p> Methods <p>The study utilises qualitative semi-structured interviews with 41 people with experience of being detained in police custody, across two police constabulary locations (North and South England). Data were analysed thematically using NVivo qualitative software.</p> Results <p>Detainees experienced stigma whilst in police custody because of identity characteristics, status, drug use, mental health, and frequent healthcare requests. Stigmatising and dehumanising interactions with detention officers (DO) and Healthcare Practitioners (HCPs) align with harms to health and wellbeing, and contributed to a degradation of dignity amongst detainees.</p> Conclusions <p>This novel research reveals that the impact of stigma in police custody settings materialise as harms to health and wellbeing, and poorer quality healthcare. We argue that stigma interactions in custody settings undermine a human rights approach to health specified in the AAAQ standards set out by the World Health Organisation, and also reproduce the inverse care law. As part of a wider recommended overhaul of police custody in England and Wales, we advise this should include urgent anti-stigma work in police custody settings to address health inequities across delivery and provision of good <i>quality</i> health care.</p>