Arthur Hume was born in Dublin, Ireland, probably sometime between 1838 and 1841, the son of Annie Parker and her husband, John Hume. Arthur attended Cheltenham College before being commissioned as an ensign in the 79th Regiment of Foot or Cameron Highlanders in July 1859. Three years later he was promoted to lieutenant. For several years he served in India, for some time holding the important administrative post of battalion adjutant. On 4 October 1864, at Murree, Punjab, he married Rebecca Charlotte Jenkins Macintire; they were to have seven sons.
Having returned to England with his family in 1871, Arthur Hume was promoted to captain; he retired from the army in October 1874. In August that year he was appointed deputy governor of Millbank prison in London. Between 1875 and 1880 he was successively deputy governor of Dartmoor, Portland and Wormwood Scrubs prisons. In 1880 he was selected for the new position of inspector of prisons in New Zealand, created in response to the New Zealand government's concerns about the state of the colony's gaols. He took up the position, which carried an annual salary of £600, at the end of the year.
Hume was given the difficult task of imposing order on the chaotic collection of prisons left after the abolition of provincial government. His office held no real power, however, until the passing of the Prisons acts of 1882 and 1883, which established a national prison system under his control. In his first report in 1881 Hume criticised the colony's prisons as being 'neither deterrent nor reformatory'. He advocated a harsh regime of the kind instituted in England under Edmund Du Cane: a system based on the progressive classification of prisoners, who gained improved conditions by exhibiting good behaviour. Under Hume's scheme, different types of offenders were to be held in different prisons and each inmate was to have his or her own cell to avoid 'contamination'. He stressed that imprisonment should act as a deterrent, and that conditions in prison should therefore be markedly inferior to the lowest reasonable standard of living in the community at large.
Economic constraints prevented Hume from fully implementing his proposals, but tougher prison conditions were introduced under his regime in the 1880s, including severe restrictions on communication between prisoners. These measures enjoyed public support, but from the start his efforts were opposed and obstructed by James Caldwell, gaoler of Dunedin prison. Hume endeavoured to have Caldwell removed from office, but without success. In 1883, however, a royal commission was appointed 'to inquire into irregularities at Dunedin Gaol'; it found evidence of serious instances of abuse of power and maladministration, and Caldwell was subsequently dismissed. Otago members of Parliament and some newspapers vehemently attacked Hume, and the minister of justice, Edward Conolly, failed to defend him properly, apparently not wanting to offend the Otago faction in Parliament. Others, however, saw Hume to be acting with firmness and integrity to implement government policy.
In June 1888 Hume was made a lieutenant colonel in the New Zealand Militia and given the important post of inspector of volunteers, with the additional post of assistant adjutant general. His other commitments meant that he was unable to spend much time on his military duties, but he worked conscientiously and in his annual reports clearly outlined the serious failings of the Volunteer Force. On 1 April 1891 he resigned as inspector of volunteers to assume the office of acting under-secretary for defence – the highest administrative position in the Defence Department – which he held until mid 1895. In these positions Hume played a significant part in the administration and inspection of New Zealand's defence forces during a difficult period of government retrenchment.
His responsibilities were increased further when, on 1 July 1890, he took over from Walter Gudgeon as commissioner of police. This appointment appears to have been a cost-saving measure and was not one Hume had sought. His complete lack of experience in police work led him to concentrate on the efficient administration of the police force, but he did press for some useful innovations, such as the establishment of a police superannuation scheme. His period as commissioner of police was, however, marked primarily by controversy over the issue of political influence in the public service. For most of this time Richard Seddon was minister of defence. It was common for ministers to intervene in the everyday administration of their departments, but under Seddon this practice developed to a new and unhealthy extent. From the outset he completely undermined Hume's authority by overturning his decisions on matters such as the promotion, transfer and disciplining of police officers. Morale in the under-strength police force crumbled as it became apparent that it was political influence and not hard work and ability which led to professional advancement.
In 1896 Seddon, now premier, gave the defence portfolio to Thomas Thompson, but he continued to play an influential part in police matters himself. In 1897 he decided to replace Hume with a capable and experienced London Metropolitan Police officer, John Tunbridge. Before Tunbridge took up his new position in November, a grave attack made in Parliament on the functioning of the police force led the government to agree to hold a royal commission. The commission uncovered evidence showing inadequacies and inefficiencies in the police force, and in particular the harmful effects of the use of political influence. Hume was subjected to exhaustive questioning over 33 days during the commission's public hearings, held between February and July 1898. It became clear that he had had no real power under Seddon and Thompson and had been reduced 'to the veriest puppet' of his political masters. The commissioners recommended that the commissioner of police have full control over personnel matters.
Without doubt Hume's time as commissioner of police was the most unsatisfactory aspect of his public service career. He had more success in the administration of New Zealand's penal system, but there too found his ambitions frustrated. When he first arrived in New Zealand he had responded to government calls to cut costs by improving administration and closing smaller prisons. But the need for economy meant that New Zealand prisons remained for some years overcrowded and often decrepit. Hume recommended the rebuilding of Auckland's prison at Mount Eden and the erection of a new prison at Mount Cook in Wellington. Work on both projects was commenced in 1882, but the large Mount Cook prison was surrounded by controversy and converted into a military barracks in 1900 because of continuing opposition from local residents. The building programme initiated by Hume eventually led to a marked improvement in the situation, but inadequate prison accommodation prevented him from properly implementing his scheme to classify and segregate prisoners.
Hume remained convinced that such a system was the best means of achieving the mix of punishment, deterrence and, where possible, reformation which he believed was the basis of a successful penal policy. During his period in office some of the harsher aspects of his original plans were mitigated, and he advocated a number of progressive measures, such as the establishment of a prison farm and a parole system for prisoners serving long sentences. He was a consistent supporter of probation and strongly opposed the imprisonment of children and the mentally ill. He also improved the training and conditions of employment of prison officers. Two major projects using prison labour on public works were carried out under his administration: the ill-fated and badly organised attempt between 1890 and 1892 to build a road linking Milford Sound to Central Otago, and the more successful government afforestation programme. The first tree-planting prison camp was opened at Waiotapu in February 1901, and the scheme was rapidly expanded with camps established at Hanmer Springs, Dumgree and Waipa in 1903–4. During the last years of Hume's administration, however, very little of a progressive nature was attempted, and increasingly he was obliged to defend his conservative penal policies against criticism by individuals and groups interested in prison reform.
Arthur Hume retired as inspector of prisons on 1 April 1909. He died at Wellington on 2 February 1918, survived by his wife and five of their sons. Hume was a competent and hard-working, if uninspired, administrator with a strong sense of duty. Although he could be brusque and high handed, he exhibited little independence of thought or action and had a marked tendency to carry out dutifully whatever directions he received. In reply to an awkward question during the royal commission hearings in 1898 he stated, 'It was not for me to think at all. I did what I was told.' His experience as an officer in the British Army and as a prison administrator in England, and his rather rigid and pedantic character, partly explain his sometimes obsequious behaviour. However, the lack of ministerial support for Hume's actions against James Caldwell, and the vulnerable position of public servants in colonial New Zealand, exemplified by his relationship with Seddon, must also be taken into account in assessing his conduct.
Hume's major achievement was the establishment of a national system of prison administration in New Zealand. His austere prison regime was efficient and effective in financial and custodial terms, but during his nearly 30 years in office became increasingly outmoded. The infrastructure of trained personnel and improved prison buildings which he developed provided the essential foundations for the more progressive penal policy followed after his retirement.