 He served in all ranks up to Chief Superintendent in Hampshire working in cities and more rural areas with diverse populations and policing challenges.McWhirter was in 1996 appointed Assistant Chief Constable (Operations) in the Wiltshire Constabulary, responsible for all operational policing.He was largely responsible for returning the policing of the summer Solstice at Stonehenge back to 'normality' after a decade of confrontation with new Age travellers and assorted Druid groups.