***Disclaimer: I am not a lawyer. Everything I wrote only reflects my personal opinion***
Thanks @Naey for the clarification re. the Beibehaltungsbescheinigung, makes sense, and glad he was able to keep his German citizenship! I am myself a U.S.-French dual citizen.
I would like to make it very clear that I am not saying that we should not follow the law. I am a law-abiding citizen as far as I am concerned. But like I mentioned, some laws are:
- stupid-yet-still-on-the-books (e.g. the Statute 18 U.S.C. § 336 makes it a federal crime to issue "any note, check, memorandum, token, or other obligation for a less sum than $1” in lieu of money.") or just
- still-on-the-books-but-not-enforceable-in-practice which is the case for the requirement for a U.S. citizen to exit and re-enter the United States with a U.S. passport. Again, when exiting, because unlike other countries, there is no systematic passport control upon exiting the U.S., the government is not even capable to flagging it (unlike re-entering where there are CBP POE controls).
So I am not suggesting that you break the law, on the contrary, you should always be a law-abiding citizen (after all, your partner doesn't want to start his U.S. citizenship by violating a federal statute 😉).
Your German/U.S. partner should do his best and exhaust all the options (incl. your Congressmen) he has to get his passport on time before leaving the U.S., but you also have to be practical and use your common sense, especially when an emergency arises and that there is no other solution.
Given the current passport applications backlog and the (very real) difficulty to obtain an appointment at a U.S. Passport Agency (even for extreme emergencies), the option of leaving the U.S. on the German passport, apply for the U.S. passport through the Consulate and re-enter the U.S. with it is a reasonable option which should only be considered as a last resort solution. And if you believe the various testimonies on this forum and others, people doing what you suggest happens more than you think...
It seems however that some black-or-white mindset people here have a problem with this thinking... 😊
Good luck!