John Callan (judge)

John Callan KC
John Callan in 1934
Justice of the Supreme Court
In office 1935–51
Personal details
Born	(1882-08-15)15 August 1882 Dunedin  New Zealand
Died	12 February 1951(1951-02-12) (aged 68) Auckland  New Zealand
Spouse(s)	Margaret Elizabeth Callan (née Mowat)
Relations	John Callan (father) Charles Gavan Duffy Frank Gavan Duffy George Gavan Duffy
Children	one son
Religion	Catholic

John Bartholomew Callan KC (15 August 1882 – 12 February 1951) was a New Zealand judge. He was a Justice of the Supreme Court (now known as the High Court of New Zealand) (1935–51).

Callan was the son of John Bartholomew Callan, a Dunedin lawyer and member of the New Zealand Legislative Council. He was born on 15 August 1882, five years after his family's arrival in New Zealand from Australia. The Callans had migrated from Ireland to Australia with the Gavan Duffy family and Callan was descended from Charles Gavan Duffy. He was educated at the Christian Brothers School in Dunedin (where he was Dux in 1897) and commenced his law studies before the Law Faculty of the University of Otago came into being. His principal instructor was James Garrow, a well-known New Zealand legal scholar. On 10 July 1913, at the North East Valley Roman Catholic Church, Dunedin, Callan married Margaret Elizabeth, daughter of James Dugald Mowat, a Dunedin stationer, and they had one son.

After graduating BA and LL.B at the University of Otago, Callan entered his father's office (Callan and Gallaway) and became a partner in the firm when his father was appointed to the New Zealand Legislative Council in 1907. He was appointed a lecturer in law at Otago University in 1912. During World War I, Callan served in the New Zealand Expeditionary Force and became a Captain. On his returned to Dunedin he continued his law practice. He also became Dean of the Faculty of Law at the University of Otago and he resumed his lectures in Torts there. Callan took silk in 1934, and he moved to Wellington.