Neil Lloyd Macky was born in Auckland on 20 February 1891, the son of Thomas Lindsay Macky, a clerk, and his wife, Elizabeth Stuart Lloyd. Polly Macky (as he was called from boyhood) was educated at Prince Albert College and Auckland University College and was articled to J. A. Tole, the Auckland Crown prosecutor. He graduated LLB in 1912, was admitted as a solicitor on 28 February 1912 and as a barrister on 13 May 1913, and set up in sole practice.
Macky volunteered for service in the First World War in April 1915 and was commissioned as second lieutenant in the New Zealand Rifle Brigade on 1 October. After brief service fighting against the Senussi, west of Egypt, he went with the New Zealand Division to France in April 1916. During the battle of the Somme, Macky served in the 1st Battalion of the New Zealand Rifle Brigade and was promoted lieutenant on 1 September 1916. On 15 September, commanding two platoons of the reserve battalion during the battle for Flers, he advanced to check a German counter-attack on the right flank, a feat that earned him the Military Cross. He became a temporary captain on 10 October 1916, was wounded on 25 December, and spent some months in hospital in England. He returned to France in 1917, was promoted captain on 11 April 1918, took part in the occupation, and was back in New Zealand in May 1919.
Resuming legal practice, in 1920 Macky and Wilson Smith formed a partnership, which did well from conveyancing during the Auckland property boom. On 6 February 1924 at Devonport he married Beryl Jean Wilson; they were to have two daughters and a son. In 1928, having bought Smith out, he merged with Russell, Campbell and McVeagh, one of Auckland's oldest legal firms. From 1931, when Harold Barrowclough became a partner, until 1942, the firm was titled Russell, McVeagh, Macky and Barrowclough, and had a distinctly military aura because of the prominence of its partners in the Territorial Force.
Macky became a major in 1926 and lieutenant colonel commanding the Auckland Regiment (Countess of Ranfurly's Own), New Zealand Infantry in 1931. Another period on the reserve, after the abolition of compulsory military training during the depression, was followed by his appointment as colonel commanding 1st NZ Infantry Brigade on 1 June 1937. This was short-lived. Poor recruiting and government concentration on the airforce led to a reorganisation and reduction of the army in 1937 in which the divisional organisation was reduced to a brigade group plus fortress troops. Mounted rifles regiments and infantry battalions were scaled down to squadrons and companies. Brigade commanders became redundant and were posted to a colonels list, with minimal duties.
Dissatisfaction with the reorganisation came to a head during a staff course at Trentham Military Camp in 1938. Four former brigade commanders, including Macky, sought an interview with Frederick Jones, the minister of defence, during which they demanded a realistic statement of the deficiencies of the army and a call for recruits. They decided that if this did not eventuate in two weeks they would issue a public manifesto. Disappointed by the minister's speech at Dargaville on 17 May 1938, the 'Four Colonels' went public on the 19th, insisting that the Territorial Force was inadequate for defending New Zealand and that volunteering was not sufficient to build it up. They received support from the conservative press and the New Zealand National Party, but were posted to the retired list. Appeals to the governor general failed to secure their reinstatement. Macky's motives for his action were not all high-minded: 'I am afraid I am too much of a Tory. To kow-tow to a bootmaker as a Minister of Defence was too much for me.'
In 1939 Macky unsuccessfully sought an appointment in the British Army. Early in October, however, the military authorities relented and he was appointed to command 21 Battalion, which sailed on 1 May 1940 with the second echelon of the Second New Zealand Expeditionary Force. Between June and November 1940 the battalion was part of a force stationed in south-eastern England to face the expected German invasion. It arrived in Greece in March 1941.
From 14 to 16 April, in an isolated position on the right flank of the New Zealand Division at Platamón on the Aegean shore, Macky's battalion successfully held up a panzer division for 36 hours. After withdrawing south, it was charged, alongside two Australian battalions, with blocking the Piniós gorge for three days to enable the ANZAC Corps to retreat. As the German armour swept through the gorge, 21 Battalion was cut off. Macky made his way with 39 men to the coast and reached Crete on 3 May. He relinquished command of 21 Battalion on 17 May and was invalided to New Zealand in September. In 1942 he became commander of the fortress troops in the Bay of Islands region.
After the war, Macky continued with his law firm, now known as Russell, McVeagh and Company. When Barrowclough became chief justice in 1953, Macky, as practice manager, ruled the firm in an autocratic manner, but recruited a group of able junior partners. After his retirement, he remained with the firm as a consultant.
Polly Macky was of medium height and upright military bearing. He was a controversial figure, known for his temper and firm opinions, but highly regarded for his courtesy and integrity. He was a keen yachtsman and commodore of the Royal New Zealand Yacht Squadron. A staunch Presbyterian, he devoted his time to charitable and educational work, as a trustee of the Edmiston Trust (a major benefactor of the Auckland City Art Gallery), St Kentigern College and St Andrew's home for old people. He died at Auckland on 4 October 1981, survived by one son and a daughter. His wife had died in 1978.