He was educated at Launceston Church Grammar School and the University of Tasmania, where he graduated with a Bachelor of Laws degree in 1984.

Hart was admitted to practice in 1985, and began work as a commercial litigation lawyer at Hill, Gunton and Patmore in Launceston, which subsequently became Rae and Partners.

He was a founding director of the Northern Tasmanian Regional Development Board from 1993 to 2005 and a director of the Inveresk Railyards Management Authority from 1998 to 2000, which focused on advancing the future of Launceston and Northern Tasmania.

He was also a member of the governing council of the Tasmanian Health Organisation North, which was charged with the delivery of health services across Northern Tasmania and operated the Launceston General Hospital from 2012 to 2015, and board member of the Launceston Church Grammar School from 2008 to 2016.

[3] On 27 June 2018, Hart repeatedly refused to back Federal Labor Party leader Bill Shorten's proposed reversal of medium business tax cuts in a radio interview with Brian Carlton, which Shorten ultimately backed down on the next day.