Are the Witnesses Vulnerable to Prosecution?

An important question, sent by Heroyalwhyness:

Just read your update of Geert’s trial and the limitations on his witness list.

All of the witnesses allowed hold similar views to Wilders. What legal assurances, pray tell, are these witnesses being given that they too will not be prosecuted for their testimony?

Do any of our Dutch readers know the answer to this question?

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