William Magee Hunter was born probably in 1833 or 1834 to a family of landed gentry in County Antrim, Ireland. He was educated at Enniskillen and Trinity College, Dublin, but cut short his studies to take part in the Crimean War. After completing the musketry course at Hythe Gunnery School, he was commissioned and appointed adjutant in the Antrim Rifles.
This unit was disbanded some time after the war, and in 1861 Hunter emigrated with his younger brother Henry to New Zealand. The following year Hunter became assistant clerk to the Auckland Provincial Council. When the Waikato militia regiments were raised in 1863 he joined the 1st Regiment as captain/adjutant and held this position until the regiment was disbanded. On the establishment of the Armed Constabulary in 1867, Hunter was commissioned as inspector (major), and given command of No 3 Division.
During 1868 renewed fighting broke out in South Taranaki between colonial troops and Maori forces led by Titokowaru. The first major engagement occurred on 12 July. At dawn on that day gun flashes at the small constabulary redoubt of Turuturumokai were seen at the main camp of Waihi, four miles away. Inspector Gustavus von Tempsky left Hunter, his junior, to hold the Waihi redoubt, and led the infantry to the rescue. The cavalry, in a state of readiness on the parade ground, were astounded when ordered to stand down, and some accused Hunter of cowardice. It was evidently Hunter's opinion that the attack on the outpost could have been a feint, and Waihi, with a store of ammunition, the main target. However, he was court-martialled, and although cleared of blame, was censured for apathy by T. M. Haultain, the minister of defence.
It has been suggested that Hunter, being high-minded and sensitive, took this criticism to heart and strove to prove his courage in subsequent engagements. Certainly, he was in the thick of the fighting during the next few months. When on 21 August Lieutenant Colonel T. McDonnell mounted his first attack on Te Ngutu-o-te-manu, Hunter was placed in charge of the rearguard on leaving the pa. The defenders, after retiring into the forest, rallied with reinforcements, and Hunter had to fight his way back to the Waingongoro River.
A further sortie was launched on 7 September, the objective being Ruaruru, but after a long, slow march the force found itself once again at Te Ngutu-o-te-manu. Hunter was in command of 108 troops, and joined Tempsky's contingent. The two sought McDonnell's permission to press an attack, but because of heavy casualties he decided to break off the action and evacuate the wounded. The defeat was accompanied by personal tragedy for Hunter, as his brother was killed.
Soon after, it was Hunter's responsibility, during McDonnell's absence, to command the disaffected troops at Waihi. His strict approach to discipline, which contrasted with the more relaxed attitude of colonial troops, was possibly inappropriate in the circumstances; he was confronted by a mutiny of the late Tempsky's No 5 Division, which brought intervention by the defence minister. This unit was disbanded, and Colonel G. S. Whitmore superseded McDonnell.
Hunter and Te Keepa Te Rangihiwinui led Whitmore's first move against Titokowaru at Moturoa, near Waverley, on 7 November 1868. It has been said that Hunter, still eager to refute accusations of cowardice, had volunteered the night before to lead the attack, and was unduly rash in mounting a frontal assault on strong defences. An alternative viewpoint is that the strength of the defences was unknown to Whitmore and that Hunter was expected to succeed. In any case the attack was repulsed and Hunter, shot in the femoral artery, bled to death on the battlefield. Criticism of him now gave way to adulation: 'The Constabulary can boast no better officer, the Colonial service no braver'.
Like other professionally trained soldiers, Hunter subscribed to a rigid and idealistic code of conduct. His suspected breach of that code was a source of personal shame; his attempts to clear his name and his posthumous acquittal may be seen as both fitting and ironic.