He has a BSc(Hons) degree in mathematical modelling from the Open University and studied operational research at the London School of Economics.

[2] Following his election to parliament, Kirby became vice-chair of the All Party Parliamentary Group on HIV/AIDS and served on the Business, Innovation and Skills and Administration Select Committees.

In 2012, Kirby was appointed as the Parliamentary Private Secretary (PPS) to the Minister for Sport and Tourism Hugh Robertson.

[4] In August 2014 Kirby was promoted to the role of PPS to the Secretary of State for Health, Jeremy Hunt.

In January 2017, he was stripped of his responsibilities for overseeing Brexit's impact on financial services, amid reports that senior financial executives from the City of London Corporation had expressed concern at his lack of business experience and inability to provide detailed answers and assurances about how the Treasury was handling Brexit.

Theresa May, however, told The Argus, that she had "absolute confidence" in Kirby as a strong advocate for Brexit.