My father was born in New Zealand (1962) to a fully Dutch father and NZ mother, but was issued Dutch nationality papers in 1986. He has never lived in the Netherlands. It doesn't look like he renewed any of these documents so I assume they are obsolete now.
Is it possible my sister (born 2000, in NZ) and I (born 1997, in NZ) could still apply for Dutch passports?
The Dutch nationality law of 1984 contained a provision whereby a dual national would lose Dutch nationality if the following conditions were met:
This law went into effect on the first of January, 1985. The provision described above was in effect through March of 2003. Accordingly, unless your father lived outside New Zealand for a time, or worked for (or was married to someone who worked for) the UN or some other international organization in which the Netherlands participates, or somehow lost (or never had) New Zealand nationality, he probably lost his Dutch nationality at the end of December 31st, 1994.
If he did live outside New Zealand for some time, however, that would have reset the ten-year clock, and, depending on when it was reset, either you or both and your sister could be Dutch. (Working for an appropriate organization or being married to someone who was might also have reset the ten-year clock.)
The rule articulated above was controversial because there was no way to avoid the loss of Dutch nationality other than by moving out of the country of birth. Eventually, the rule was changed back to something more similar to the original 1892 nationality law, which provided that one could reset the 10-year period by getting a declaration of nationality or a passport. This took effect on 1 April 2003.
For two years, beginning on that date, people who had lost their nationality under the 1985-to-2003 rule could regain their Dutch nationality by "option," making a declaration to that effect. This possibility ended on March 31st, 2005. However, the two-year period was somewhat controversial because a number of people were not aware of the change in the law and did not find out in time to take advantage of this option procedure. At this late date, it seems unlikely that there would be any relief for these people, but controversy is constant in Dutch nationality law, so there have been frequent changes to the details. For example, earlier this year, the ten-year period was changed to thirteen years. It might therefore be worthwhile to keep your eye on it.
In any event, you should not take my word for this. It's very possible that I overlooked something. The best way to be sure is to ask the Dutch consulate for a formal determination.
