As a European I am not particularly invested in how the US legal system wants to protect non-citizens "rights". I just hope that the EU learns how effective immigration deterrence looks and can make the appropriate legal changes, here in Europe we do not have attachments to centuries old legal concepts, so I think this issue just does not appear here.

One idea which should be explored, both in the US and the EU, is that all lawsuits against immigration decisions have to be paid, either ongoing or up front, by the person who would be affected by the immigration enforcement.