Dual citizenship restrictions on MPs

This week in Melbourne I attended a lecture at which I learnt that here one is barred from standing for parliament if he or she is a dual citizenship holder. This means that every MP in the Australian House or Senate in Canberra is an Australian citizen only. As far as I know, no such rule applies in New Zealand, although the Harry Duynhoven case in 2003, in which a special law was passed to allow Duynhoven to continue as an MP despite breaking the Electoral Act by reapplying for his Dutch citizenship, while still an MP. The Christchurch Press...