David joined Northumbria Police as a Police Constable in 2000 after previously serving as a Special Constable. He spent approximately six years working as a response officer. He passed his Sergeant's examination in 2003 but chose to remain a constable so that he could pursue the policing role he particularly wanted – traffic.

In 2006, David joined Northumbria Police's Traffic Department, where he spent some of the most fulfilling years of his career. He also voluntarily trained as a Family Liaison Officer, supporting families following bereavement after fatal road traffic collisions.

David was immensely proud of being a police officer. Even after suffering catastrophic injuries while on duty in 2010, he spoke publicly about his determination to return to the job he loved