Frederick Revans Chapman was born at Wellington, New Zealand, on 3 February 1849. He was the fifth child of Henry Samuel Chapman, puisne judge of the Supreme Court of New Zealand, and his wife, Catherine Brewer, the daughter of an English barrister. When he was three years old his father was appointed colonial secretary of Van Diemen's Land (Tasmania), and the family moved to Hobart. Two years later they settled in Melbourne, where Frederick attended the Church of England Grammar School. In 1864 he went to London to study at King's College.
In 1866 his mother and three of his siblings drowned in a shipwreck. This tragedy reinforced his early maturity, making him serious of mind, resourceful and thoughtful towards others. It also spurred him on to even greater efforts in his studies in order to give meaning to his life and satisfaction to his bereaved father, whom he revered. Later that year he departed for Europe, where he furthered his education in France and in Germany.
In January 1868, back in London, Chapman entered the Inner Temple and over the next three years he and his brother Martin prepared themselves for admission to the English legal profession. On 1 May 1871 they were called to the Bar. Frederick stayed on in England until early 1872 furthering his legal knowledge and experience. In August 1872 he arrived in Dunedin, where he joined his father who had, since 1864, been puisne judge for Otago and Southland. Chapman was admitted to the local profession in October 1872, and over the next 31 years he conducted a busy legal practice from his base in Dunedin, in later years in partnership with Smith, Sinclair and White.
Frederick Chapman played an active role in the affairs of the emergent New Zealand legal profession. He assisted in the production of New Zealand's early law reports, notably as editor of the New Zealand Jurist in 1875 and as a member of the Council of Law Reporting. From 1876 to 1878 he was sole law lecturer in the University of Otago, and in 1879 he helped form the Otago and Southland District Law Society, serving as president in 1892. From 1899 to 1902 Chapman was actively involved in New Zealand's pioneering system of industrial relations in his position as chairman of the Board of Conciliation for the Otago and Southland Industrial District.
Chapman also occupied himself with a wide range of other activities. In 1875–76 he was a town councillor, and throughout his time in Dunedin he wrote for the local press. His interest in Maori antiquities led to his being acknowledged as a leading ethnologist, and his 'Notes on moa remains in the Mackenzie Country and other localities' (1884) and 'On the working of greenstone or nephrite by the Maoris' (1891) were regarded as classic papers in their field. Chapman himself collected extensively on the rich Otago sites, and he was a member of the Polynesian Society from its foundation in 1892 until his death. He also developed an interest in botany, claiming that the flora of New Zealand was unique. In 1885 near Dunedin he discovered the red manuka, and this came to bear his Latinised name.
On 9 January 1879 at All Saints' Church Chapman married Clara Jane Cook, the daughter of an English solicitor practising in Dunedin. They had five children: three daughters and two sons.
Chapman was appointed a judge of the Supreme Court of New Zealand in Wellington on 11 September 1903. He was the first native-born New Zealander to reach the Bench. During the years 1903–7 most of Chapman's time was spent as president of the Court of Arbitration. Here he distinguished himself as an industrious judge, but his judicious approach and his conscious efforts to balance out the interests of workers, employers and the general public won him mixed reviews. Unionists perceived him as favouring employers' interests, and a series of strikes in 1906 and 1907 led to a revision of the conciliation and arbitration system in 1908.
From 1907 to 1921 Chapman served in the Supreme Court, exercising civil and criminal jurisdiction. He was painstaking, known in legal circles for his scrupulous fairness. In civil matters he was one of the most scholarly of the Supreme Court judges of the time, an essentially cautious jurist whose decisions were securely grounded in legal authority. Later New Zealand judges have repeatedly relied on Chapman's judgements in the knowledge that they were based on extensive legal research, and were precisely reasoned. In criminal matters Chapman was regarded as pre-eminent because of the experience, learning and aptitude he showed in this work.
Chapman took a firm line with offenders he thought required deterrent sentences. His sentencing of the Maori leader Rua Kenana was criticised as being unnecessarily punitive; eight of the jurors protested in a petition to Parliament. But he was renowned for his fairness and insight in criminal trials, and he played an important role in the shaping of New Zealand's criminal procedure and rules of evidence. He was on the Bench in 1920 when evidence from fingerprints was admitted for the first time in New Zealand.
During his judicial career Chapman was active behind the scenes in giving advice to the government on law reform, particularly in criminal law and procedure. He wrote on legal, historical and contemporary world events, and maintained his interest in languages (he was fluent in French, German and Italian). It was said that 'no line of study was without interest to him and his quest for knowledge endured throughout his life'. Chapman placed much importance on the well-being of his family, from whom he derived considerable emotional support. He was profoundly affected by the loss of his two sons, the younger in 1915 in the war in Europe, and the elder by suicide the following year.
Chapman retired from the Supreme Court Bench in 1921, but remained active in many fields. Between 1921 and 1924 he was commissioned four times to act temporarily on the Bench, and he served as compiler of statutes supervising the compilation and amendment of legislation. For periods between 1923 and 1927 he was chairman of the War Pensions Appeal Board. Chapman also pursued his interests in research and writing on legal topics and Maori culture and artefacts. He ultimately gave his ethnographic collection to the Otago University Museum, which named the gallery housing the Maori collection after him. Chapman's interest in historical research was grounded in his belief that history was the 'reflection of the life and being of a people', and that it enabled succeeding generations 'readily to ascertain who and what they are, by considering who and what those parents were who introduced them to this world'.
In retirement Chapman became more interested in science and nature, and produced work on astronomy, the origin of life and the age of the earth's crust. Almost to the last he continued to write his reflections, pursue his interest in his own family's history and maintain an extensive correspondence with his family and many friends. He died at Wellington on 24 June 1936 of heart failure. He was buried two days later after a funeral service at St Paul's Cathedral Church at which tributes were paid to his versatility, vigour, energy and humanity. Clara Chapman died on 15 April 1940. Their daughter Sylvia was the first woman to serve on the Senate of the University of New Zealand.
Frederick Chapman believed in 'attending accurately to the smallest details', and observed that 'the elements of greatness in a great man are not always to be found in great deeds, but in the minor acts by which he ensures that no mistake is made'. This approach at times made him appear to be rule-bound and lacking in vision. At the same time, his rational and painstaking approach meant that others could be assured of the highest standards in his personal and professional life. Chapman retained a deep-rooted respect for individual humanity, as evidenced in his attempts to soften the impact of legal rules, and in his courteous behaviour towards the public and his legal colleagues, friends and family.