Imagine a large group of German citizens wants to stop Germany from accepting refugees.
Are there any legal options for them to enact this?
Can they, for example,
- initiate a referendum on whether or not the borders should be closed for foreigners, who don't satisfy some criteria (like skill in a profession in demand, certain level of education), or
- make the parliament discuss the issue via the Austrian popular ballot mechanism (Volksbegehren in German, if enough people sign a petition, the parliament is obligated to discuss the issue)
If yes, what are such options (ideally with references to corresponding laws) ?
Note that I'm interested in this question from a purely technical (legal) point of view. I'm not interested in whether it's moral or not to close the borders.