I find it fascinating that for a repository of German law, written in German, the README and commit history are all in English. I wonder if that will have the effect of scaring off any would-be contributors.
All Germans I have ever met have had excellent English. Certainly good enough to read short English commits with only the occasional dictionary reference required.
The Eurobarometer report from 2006 says 56% of Germans speak English.
But I suspect that rather underestimates the case here. There is a huge difference between someone checking a box on a form that says they can speak English and being able to parse short messages in English.
And given only fairly educated, tech-savvy Germans are likely to participate in this, I think the negative effect from English commits is straight up zero, or at worst incredibly low.
It's been a few years since I visited Germany, but it varied quite a bit with region, level of education, and age (pretty universal among younger Gymnasiasten, very rare among older people in former East Germany, particularly more rural parts).
I have gotten reactions from "Why did you bother to learn German? Everyone here speaks English" to "Gott sei dank! Du kannst Deutsch" ("Thank god! You can speak German")
Actually, it is not "the government" doing this. It is somebody scraping an official web site containing every law, processing it and pushing the result to this repository.