The Bild recently argued against political participation by foreigners in the German party SPD. It seems that one doesn't need to be a German citizen to be a member of the SPD and take part in party activities such as voting.
I have two questions:
- Is this common among German parties, or is the SPD an outlier in this regard? (I was able to find the answer regarding memberships for the CDU (they allow it for Europeans with some restrictions) and Linke (they allow it), but not other parties like Grüne, FDP, AfD, etc).
- Do other parties restrict political participation of party members based on their nationality (eg they can be members, but not vote on (some) party matters)?
If it's not too broad, it would also be interesting how other European parties handle this issue.