The bivak guy who tried it out, has published his story on his Dutch website named blindedarm.com. It's a hilarious story. It's shows he can't walk freely like a Muslim burka can. But also that police officers are confused, especially when he points out their unconstitutional discrimination. It also leads to funny pictures like this one: bivak guy showing his id. In the end, he meets an police officer who does seem to remember the law and stops him. But when his boss arrives, by bike, the boss agrees it's not legal, but that he does not act on it (just like they do in cases of softdrugs). Even after bivak guy asks to be arrested, he wants none of it. Bivak guy does not have to show his face.
The police officer was of course right, in The Netherlands it's not allowed, by law, to walk around with a mask, bivak or other dresses that hides the face. It's the politicians who sowed confusion by debating an partial ban of the burka. As if it was legal in the first place. They have created this special position for Muslims. It's also the politicians who have send out special instructions to the police to avoid Muslim sensitivities. They are creating more and more a police force that no longer base it's actions on the law, but instead prefers to act on political correctness and their own ideas of fairness. A scary direction.