Bund.de is the official German government portal for doing government-related paperwork online.
They have now created their own Mastodon instance at social.bund.de which contains some official accounts. You can find them on the instance's directory page:
➡️ https://social.bund.de/explore (in German)
This is a really promising sign! The Fediverse can allow citizens to interact with public officials without having to give away personal data.
Legal.Social is the Mastodon instance for legal debate.