BTW at the time of the picture he was serving in the Kent County Constabulary.
They have a museum and a museum website with a fair bit of period exhibits and information.
http://en.wikipedia.org/wiki/Kent_Police_Museumhttp://www.kent-police-museum.co.uk/core_pages/index.shtmlYou might already be aware of that but if that isn't where you got your picture from they would probably love to have a copy of it.