This thesis looks at how users of regional or minority languages engage with their right to a fair trial in the criminal justice system under the United Nations and Council of Europe systems of human rights. This is a socio-legal study of Irish speakers and Deaf, Irish Sign Language users in Ireland, investigating the lived experiences of those who have interacted with the criminal justice system. Identity and identity perception are central to this project. Identity is both internally constructed and externally imposed on individuals. When the internally constructed identity is misunderstood, oversimplified or not visible to the majority or the authority, an othered minority can be treated with unfair bias and stereotyped. In the course of the research, two particular stereotypes or tropes arose, which Irish-speakers and Deaf people were faced with generally when they interacted with the criminal justice system. Firstly is the ‘créatúr’, coming from the Irish word meaning pitiful one, wretch or creature. It applied to Deaf people who were not seen as autonomous, competent beings, but rather as disabled and incapable of independent life. Secondly is the ‘slíbhín’ or the sneak or troublemaker. This narrative applied to both Irish speakers and Deaf people, but was most attributable to the former. The use of Irish was largely seen as malicious, and an attempt to frustrate the legal process, rather than an exercise in identity. The interviewed regional or minority language users were not seen in light of their true identities and this impacted their journeys through the criminal justice system. This research explores beyond the limited impact of the minimum standards of the right to a fair trial, incorporating external factors that impact the right to a fair trial for RML-users, such as language stereotypes, police culture, and access to justice.