How prostitutes that aren't forced or exploited still count as victims by the Dutch law
It's something that I've written about before, but not something I've gone into depth about yet. Because when people think about victims of trafficking they think about a prostitute that is either forced or exploited. But the Dutch law doesn't require prostitutes to be forced or exploited at all, to be branded as victims of trafficking. In fact, a prostitute who willingly choose this profession, and has never been exploited, can still be counted as a victim of trafficking according to the Dutch law.

The exact part of the Dutch law I'm referring to is article 273F section 1 sub 3. The law is somewhat of a copy of a similar rule from the human trafficking law as defined by the United Nations. With one big difference however. Where the UN's version of this trafficking law requires prostitutes to be either forced or exploited to be seen as victims, this isn't the case in the Dutch version.

This is the version UN's version of the same rule under article 3 section A:
"Trafficking in persons" shall mean the recruitment, transportation, transfer, harbouring or receipt of persons, by means of the threat or use of force or other forms of coercion, of abduction, of fraud, of deception, of the abuse of power or of a position of vulnerability or of the giving or receiving of payments or benefits to achieve the consent of a person having control over another person, for the purpose of exploitation. Exploitation shall include, at a minimum, the exploitation of the prostitution of others or other forms of sexual exploitation, forced labour or services, slavery or practices similar to slavery, servitude or the removal of organs;

Yet the Dutch law states under article 273F 1.3
"The person who recruits, takes along or abducts another person with the intention to make that person available in another country to carry out sexual acts with another person in exchange for payment;"

Now, in the case of the version of trafficking from the United Nations, you cannot recruit or transport someone for prostitution if you coerce them, exploit them, deceit them etc. But the Dutch law states none of these things. Simply taking someone with you across the border is already enough to call it trafficking, even if there's no coercion whatsoever, no exploitation of any kind, and the prostitute in question is doing it completely out of her own free will, without being deceived or whatever.
Now, the United Nations would not call this trafficking, since all human trafficking is based on the concept of some form of coercion and exploitation. But the Dutch law does see this as human trafficking when there's no form of coercion or exploitation involved, as also the National Rapporteur explains in her reports.

Let's make an example to make it more clear. Let's say you're driving through Germany, and somewhere along the road you come across a girl that asks you if you can give her a ride to Amsterdam. Why? Because she wants to work in the Red Light District. She's alone, she's not being coerced or exploited, and you're a kind person, so you agree to give her a lift to Amsterdam.
Now, as soon as you cross the border with her, you have officially become a human trafficker and a criminal under the Dutch law, and the prostitute has become your victim. Why? Because you took her along with you with as a goal so she can become a prostitute in Amsterdam. 
It doesn't matter that you didn't coerce her, that you didn't try to exploit her, that you didn't even ask money for the ride. Giving her a free ride across the border is enough for the Dutch law to make you into a criminal.
Under the same law from the United Nations however, there's nothing wrong with it. According to their law, you are not a criminal when you do this. Why? Well, you didn't deceit, coerce, exploit or do any of the other things mentioned in the law which would make it a criminal act. 

But now let's take another example. Let's say I have a friend back in Romania. I know her very well, and she's looking for a quick way to make a lot of money. So I say to her she should come here, to work in prostitution. I'm not forcing her, I'm nearly telling her it's a good option. Now let's say she actually takes the step and does it. She moves to Amsterdam and starts working here in prostitution, because of my recommendations for it. In that case you could say that I've recruited her. Just like other people recruit people to work in a call center for example, or anywhere else.
Now, under the United Nations I'm save. She's not a victim of trafficking, because I didn't force or exploit her. And I'm not a suspect or perpetrator, since I didn't do anything illegal by the law of the United Nations. The Dutch law however doesn't require there to be any form of coercion or exploitation to be present in these kind of cases, meaning in this case it is human trafficking! Yes, it's weird isn't it? By international law I'm not a criminal in this case, but by Dutch law I am.

As you can see there's no need to be coerced or exploited in Holland to be counted as a human trafficking victim. While the United Nations make it clear some form of coercion or exploitation has to take place, the Dutch law doesn't require this for human trafficking when you take a prostitute with you, or when you recruit her. 
Now, you may be thinking this law is perhaps old, or doesn't get used much. Well, think again. In 2010 in in total 19 trafficking cases the public prosecutor used this law to try and convict people for helping prostitutes, which in 11 cases were even found guilty. The National Rapporteur calls that 'unjust', since in 8 of these cases people were not convicted for trafficking, because according to the judge there was no form of coercion or exploitation. In short, the National Rapporteur calls out to convict people for not coercing or exploiting prostitutes. She wants people to go to jail for human trafficking, even though they did not exploit or coerce the prostitutes. And perhaps this may also explain the often heard complaint that 'prostitutes don't see themselves as victims', and don't want to cooperate with prosecuting the other person.  And to give you an idea, in total there were 83 convictions of human trafficking in 2010, of which 11 were for this specific law that does not require any form of exploitation or coercion, that's about 13% of the cases, in which people are being convicted for something that doesn't require any form of coercion or exploitation.

On top of that also each year the Dutch Royal Marshals (KMar), which operate mostly at the borders and at the airports, report annually about 300-400 'possible victims' of these specific kind of cases a year. That's right! Each year 300-400 prostitutes get reported as possible victims of human trafficking which doesn't involve any kind of coercion or exploitation! Free prostitutes are registered as so called 'presumed victims', and also presented as such by CoMensha and the Dutch National Rapporteur Human Trafficking.
The most interesting part is the fact that these reports of these kind of cases has been increasing heavily since around 2010-2011. In fact, right around the same time as the number of presumed victims of human trafficking in prostitution seemed to explode all of the sudden, was the same period when un-coerced an un-exploited prostitutes where increasingly being reported as victims of trafficking. The below figure states the number of possible victims of trafficking in prostitution in Holland. The orange figure shows all the reported 'possible' victims in total, including prostitutes of whom they suspected weren't forced or exploited in any way. The blue figure however shows you what happens if you take out the cases that fall under this rule, which victimizes prostitutes that are neither forced or exploited in any way.

As you can see the huge increase of 'possible victims' is a lot lower if you don't count in all those cases involving prostitutes who are not coerced or exploited in any way, but that according to the Dutch law are still seen as victims of trafficking anyway. Quite a big portion as you can see. Especially from 2012, the record number of reported 'possible' victims ever in Holland is a lot lower if you don't count prostitutes that aren't being forced or exploited. 
In fact, if you look at these numbers, and take the record amount reported ever, including only 'possible' exploited and forced prostitutes, and not cases that don't require prostitutes to be forced or exploited, you come down to a very low percentage. On the estimated 20.000 sex workers in Holland, 789 was the highest reported possible victims of exploitation and coercion in prostitution ever. That's a little bit less than 4% of all the sex workers in Holland. And that was the record number!

Dutch version