Susan Jane Denham,[1] SC (née Gageby; born 22 August 1945[2]) is a retired Irish judge who served as Chief Justice of Ireland from 2011 to 2017, she was the first woman to hold the position.

[7][8][9] She was involved with the Free Legal Advice Centres while studying in Dublin and was a founder and president of the Archaeology and Folklife Society at Trinity College.

[6] She became a senior counsel on the same day as future Supreme Court colleague Mary Laffoy.

She was involved in several leading cases while a junior barrister and a Senior Counsel, particularly in the area of judicial review.

[12][13] She was considered for appointment to the role of President of the High Court in 1994, but declined to have her name put forward.

[15][10][11] In Kelly v Hennessy in 1996, she outlined criteria for a court to consider the evidence of the existence of nervous shock in Ireland.

[21] She was the first woman appointed to the office and as a member of the Church of Ireland, she was the first non-Catholic to hold the position.

[23] During her tenure as Chief Justice, the Supreme Court issued suspended declarations of unconstitutionality for the first time.

[11] The possibility of delaying the effect of a court declaration that a piece of legislation is contrary to the Constitution was first explored by Denham in A v Governor of Arbour Hill Prison.

[27] She corresponded with the Office of Public Works over the lack of heating in the Four Courts, threatening to cancel sittings if the issue was not resolved.

[30] In her capacity as Chief Justice, she oversaw the administration of the Presidential Declaration of Office at the inauguration of President Michael D. Higgins in Dublin Castle in November 2011.