He was appointed commissioner following the retirement of Mike Bush - who did two three-year stints as the country’s top cop.
Coster has had a varied and steady rise up the ranks.
He joined the police in 1996 and worked across all policing in the Counties-Manukau and Auckland City districts, including as a detective from 1996-2003.
He was the Auckland Area Commander from 2009-2013, the Auckland Armed Offenders Squad commander from 2011-2013, Southern Police District Commander from 2013-2015, the Ministry of Justice deputy’s chief executive 2016-2018 and had police deputy roles from 2018-2019.
In 2004, Coster graduated with a Bachelor of Laws with Honours from the University of Auckland and that same year admitted as a barrister and solicitor to the High Court.
After a stint with Auckland Crown prosecutors Meredith Connell, Coster returned to the police ranks.