This thesis examines the central research questions as to what extent the Irish language plays a significant role in the Irish legal system and how parties seeking to utilise the legal in the legal system fare. The thesis applies standard jurisprudential research methodologies in analysing the key legal developments which have occurred in Ireland from independence in 1922 until today where Ireland is a modern constitutional democracy and member of the European Union. The role of the 1937 Constitution, in particular, is key given the strong legal reliance upon its text in determining the legal status of the Irish language and the extent to which that status can be relied upon in legal proceedings. By interpreting case law from the foundation of the State through until the seminal case of Ó Beoláin in 2001 the gradual development of Irish language rights can be charted. The implications of the Ó Beoláin decision are examined including many of the cases which came about in the immediate aftermath of the case. Among the consequences of the Ó Beoláin case was the Official Languages Act, 2003 which imposed new obligations upon the State and State agencies as well as notionally providing additional supports for those seeking to access justice through the medium of Irish. The effectiveness of this legislation is examined together with recent developments such as the trend towards legal realism and the implications arising out of the Irish language’s interaction with international law. Legal education and training through the medium of Irish is identified as a key factor which contributed to all of areas identified. The provision of services and the ability to access justice through the medium of Irish ultimately depends on there being professionals with sufficient Irish to provide services. The dissonance between the notional status of the Irish language and the reality faced by those seeking to access justice through the medium of Irish is a constant theme throughout the thesis.