Paul has been a public servant since 1993. He started his career at Te Puni Kōkiri and has worked extensively in Treaty settlements, including as the Director of the Office of Treaty Settlements from 2003 to 2008. He has also worked at the Treasury, Ministry of Justice and ACC. From 2011 to 2015 he was the Deputy Chief Executive at the Department of Internal Affairs (DIA), where he was responsible for local government policy, gambling regulation and the Community and Voluntary portfolio amongst other things. From 2015 to 2018 Paul was the Chief Executive at Manatū Taonga, Ministry for Culture and Heritage.
In October 2018, he moved back to DIA as Chief Executive, a role in which he is also the Secretary for Local Government and the Government Chief Digital Officer (GCDO). As functional leader for government ICT, the GCDO is responsible for ICT-enabled transformation across government agencies to deliver better services to citizens.