Question about sovereign citizens

Hello everyone,

I am not sure if this is the rightplace, hopefully it is.

I am researching the dutch sovereign citizens movement, with a focus on policies that could help curtail the growth/decrease the size of the movement. For this I also want to look at potential policies of other countries, mainly the US and Germany(both have a long history with these groups). My question is thus the following: Are there any state/federal policies that deal with this people?

Thanks in advance!