Garnet Hercules Mackley CMG (9 December 1883 – 24 April 1986) was a New Zealand businessman, railways manager and politician.

During his tenure, Mackley worked hard to improve the standard and range of services provided by the railways.

[2] The car's success encouraged him to order the construction of railcars that were to serve the railways for many years, specifically the Midland, Wairarapa, Standard, and Vulcan classes.

[3] In 1940 he retired,[4] and was made managing director of the Whakatane Paper Mills.

Mackley then entered politics, becoming a Member of Parliament for the New Zealand National Party.