Tom O'Higgins was born in Cork in 1916. He was the son of Dr. T.F O'Higgins and the nephew of Kevin O'Higgins. He was educated in Dublin, at University College Dublin and King's Inns. In 1938 he qualified as a barrister and was called to the Bar. In 1954 he was called to the Inner Bar.
In 1948 O'Higgins was elected to Dáil Éireann as a Fine Gael TD for Laois-Offaly. In the second Inter-Party government (1954-1957) O'Higgins was appointed Minister for Health. During his period as Minister for Health he introduced the Voluntary Health Insurance Board (VHI). During the 1960's O'Higgins worked closely with Garret FitzGerald and Decalan Costello in re-shaping Fine Gael. O'Higgins was chosen as the Fine Gael candidate in the 1966 Presidential election. He faced the Fianna Fáil candidate, Eamon de Valera, who was seeking re-election. O'Higgins came within 1% of beating de Valera - much better than he had hoped.
In 1973 O'Higgins was again chosen as the Fine Gael candidate in the Presidential election. This time he faced former Fianna Fáil Tánaiste, Erskine Hamilton Childers. Childers was elected by 635,867 votes to 578,771. The following year, following the sudden death of Erskine Hamilton Childers, O'Higgins swore in Cearbhall Ó Dálaigh as President of Ireland. That same year he became Chief Justice of the Supreme Court. He held that post until 1985 when he was appointed a Judge of the EU Court of Justice. He remained there until 1991.