May a Dutch citizen enter the Netherlands using a foreign passport?
EDIT:
I have just noticed that the linked page on the Dutch identification requirement has changed. I do not know when or why it changed. It now reads
Identificeren bij dubbele nationaliteit
Heeft u naast de Nederlandse nationaliteit een andere nationaliteit? Dan kunt u zich in Nederland identificeren met uw Nederlandse identiteitsbewijs. Dat is geen wettelijke verplichting, maar werkt in de praktijk voor de meeste situaties het makkelijkst.
Translation, with emphasis added to show changes from the earlier version:
Identifying yourself if you have dual nationality
If you have another nationality in addition to that of the Netherlands, you may identify yourself in the Netherlands using your Netherlands identification document. This is not a legal requirement, but is simplest in most situations.
Original question:
In the Netherlands, there is a legal requirement to be able to show identification. Dutch citizens who are dual nationals must use their Dutch identification to comply with the law.
Identificeren bij dubbele nationaliteit
Heeft u naast de Nederlandse nationaliteit een andere nationaliteit? Dan moet u zich in Nederland identificeren met uw Nederlandse identiteitsbewijs.
Translation:
Identifying yourself if you have dual nationality
If you have another nationality in addition to that of the Netherlands, you must identify yourself in the Netherlands using your Netherlands identification document.
It's not clear to me whether the law is meant to include in its scope the inspection of passports on crossing external borders, but it is certainly possible to read it as such. Government examples of situations in which authorities can demand ID do not include border controls; see, for example, https://www.rijksoverheid.nl/onderwerpen/identificatieplicht/vraag-en-antwoord/wie-mag-vragen-naar-mijn-identiteitsbewijs-en-wanneer.
But the file Informatieblad Identificatieplicht says that the "Marechaussee can ask for your ID in the course of their duties." The Marechaussee is the border control authority for the Netherlands.
So the question, as indicated in the title, is whether a Dutch national who also has another nationality can use the foreign passport to enter the Netherlands. If it makes a difference, consider that the traveler lives outside the Schengen area and the EU, and is visiting for a short time rather than immigrating.
Best Answer
EDIT: ...als je door de douane gaat, zit je op internationaal grondgebied. (...) Dit heeft echter weinig te maken met rechtspraak. In het Verdrag van Tokyo is vastgelegd wie en wanneer jurisdictie heeft. In het geval van Schiphol heeft de Nederlandse wetshandhaving de jurisdictie, welke kan lopen tot in het vliegtuig zelf. Meaning: the law, if any, also applies to passport control at the border. END EDIT
So you are saying the law states that if you have dual citizenship you are required to show the Dutch ID. I have not been able to pin down the law that states this requirement. The link you posted to an information leaflet of the Dutch government states clearly that you should show your Dutch ID if you have one, but that doesn't mean it's the law. The law that deals with the requirement to be able to identify oneself does not say anything about dual citizens. http://wetten.overheid.nl/BWBR0006297/2014-01-20
On the other hand, on https://www.rijksoverheid.nl/onderwerpen/nederlandse-nationaliteit/inhoud/dubbele-nationaliteit it is stated that the Dutch government does not keep track of dual citizenship of its citizens anymore (since 2014). This would explain why the information leaflet tells you to use your Dutch ID: it saves time, for the people that have to make sure you are not breaking any laws for being in NL. If you show the police your US passport and there is no mention of an entry date to Schengen in their system, they have to check that you are not staying in NL illegally and that could just be prevented if they knew that you are a Dutch citizen.
So my answer to your question: you do not get a fine for showing your foreign passport at the border, because you do not break any law by doing that. However, you will be asked your estimated length of stay. If you do not intend to stay any longer than is allowed for any other US citizen, there is no problem. Possibly they recognize you in their database as a Dutch citizen and then if you cannot explain why you didn't show your Dutch ID, you will have to explain. That's all. The same goes for ID controls in the country, for example if you commit a traffic offence. There is no law that states that you get fined for showing a foreign ID as dual citizen, but police does have the mandate to control your right to be there. If you cannot prove that you are staying legally they have to hand you over to the "alien police" (yes, that's what they call it in NL). If you happened to enter for say 30 days, but then stay on for a year because you changed your mind you might get in trouble with the police if you do not show your Dutch ID (because you are not carrying it on you). It has probably happened before and that's why they don't like it: it's a huge waste of time and resources. I'm judging this all based on my experience of living in the Netherlands for 10 years in my youth: There are many rules that you have to follow, but if you do not behave you will only get punished or fined for breaking the law, not for breaking a rule. Of course you don't make many friends if you break too many rules...
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