As a police officer for 30 years, Gillian has had direct experience of the criminal justice system. She has served on a number of national committees ranging from terrorism to roads policing and led on major infrastructure projects for the police. Gillian also chaired the Local Criminal Justice Board in Bedfordshire for five years, with a particular focus on young offenders and domestic violence.

Gillian has previously served as a trustee with a number of charities, including Child Victims of Crime and The Foyer. She also currently works with the charity CHICKS, which provides holidays for disadvantaged children.