Davitt, Cahir (1894–1986), judge, was born 15 August 1894 in Co. Dublin, second son and fourth child among six children of Michael Davitt (qv) of Straide, Co. Mayo, and Mary Davitt (née Yore) of Michigan, USA. The family lived in the Land League Cottage, Ballybrack, Co. Dublin, before moving to several addresses nearer the city. Educated at CBS, Kingstown (Dún Laoghaire); Presentation College, Glasthule; and O'Connell Schools, Dublin, he later attended UCD (from 1911). At UCD Davitt was a well known member of the college debating society – the Literary & Historical Society (L&H) – from 1912, and his contemporaries within the society included John A. Costello (qv) and Arthur Cox (qv). In his contribution to Centenary history of the Literary and Historical Society of University College Dublin he recounted the good-natured but high-spirited debates that took place over the admission of women to the L&H. He graduated BA (1914) and LLB (1916), and matriculated at the King's Inns (1913). Called to the bar in January 1916 and made a bencher in 1927, he practised for four years on the Munster and Connacht circuits.
Initially a supporter of the Irish parliamentary party, he reluctantly joined the Irish Volunteers in November 1915 and, although not a member of Sinn Féin, he addressed election meetings in east Mayo in 1918. In July 1920 he accepted an appointment as one of two circuit judges of the dáil courts, the other appointee being Diarmuid Crowley (qv). According to Mary Kotsonouris, Davitt was the ‘kingpin of the fledgling judicial system throughout Munster . . . and gave it an authority and status that could not have been achieved without some hierarchical framework . . . [He] brought in his person the magisterium of the law’ (Retreat from revolution, 31–2). Unlike Crowley, who was arrested for holding his court in public and refusing to disperse when asked to by the official authorities, Davitt was more pragmatic in his approach. This attitude served him well, as was seen when Crowley was arrested not long after starting on circuit while Davitt remained at large and functioning as a judge.
A supporter of the treaty, he was appointed the first judge advocate general of the national army in August 1922. His first duties were to draft a code of discipline, The general regulations as to discipline (November 1922), and organise the legal section of the adjutant general's office. In response to the guerrilla tactics of the anti-treaty forces he also produced Trial of civilians by military courts (October 1922). Initially reluctant to join the army, he soon realised that without a military rank he had no authority to give orders, so on 13 June 1923 he enlisted as a major-general. Outside his army duties, he served on the judiciary committee (1923–4) established to advise the government on the establishment of the courts system of the Irish Free State.
As conditions in the country normalised, the army was reduced in size and Davitt's rank reduced to that of colonel. He resigned his commission in 1924, though he continued part-time as judge advocate general (at a yearly salary of £750) until November 1926, when he was appointed a temporary assistant circuit judge (1926–7). Between 1927 and 1945 he was a circuit judge for Dublin city and county, and chairman of several government inquiries and commissions, including the tribunal of inquiry into the causes of the Dublin tramway strike (1929), the derating commission (1929–30), and the civil service compensation board (1929–30, 1945–66). He was also a member of the tribunal of inquiry into dealings in Great Southern railway stocks (1943). In 1945 he was appointed a judge of the high court (1945–51), and served on the Locke's distillery tribunal of inquiry (1947). In 1951 he was appointed president (1951–66) of the high court. From 1961 to 1963 he served as chairman of the commission on driving while under the influence of alcohol, the final report of which led to the introduction of the breathalyser test. After his retirement in 1966 he became chairman of the Medical Bureau of Road Safety (1968).
A keen sportsman in his youth, he was president of the Leinster branch of the IRFU (1930–31), a member (1935–62) and president (1936–7) of the central executive of the IRFU, and a founder member and first president of the Leinster branch of the Irish Squash Rackets Association (1935–6). He was also a founder member and first president of the NUI Graduates Association. He died 1 March 1986 in Dublin.
He married (1925) Sarah Gertrude, daughter of Thomas J. Lynch and Sarah Lynch (née McPhilips). They had five children and lived at 5 Argyll Road, Dublin; Dungriffin, 2 Sydney Parade Avenue, Dublin; and 88 Lower Churchtown Road, Dublin.