Check out this: https://github.com/JesseKPhillips/USA-Constitution
It's not an official source, but they added the history with correct dates etc. Very cool concept!
Our student organisation (for CS students) also has our organisation statutes in git: https://github.com/abakus-ntnu/statutter
In Poland, bills that amend laws are formed in a rigid way. They consist of a long list of recitals like:
"article such-and-such is amended to 'new text goes here'"
or
"after article 1.2.3, article 1.2.3a is hereby inserted with the following content: 'text goes here'"
(random example: http://prawo.sejm.gov.pl/isap.nsf/download.xsp/WDU2019000180...).
It has occurred to me that this kind of bills should be automatically parsable and convertible to a diff. Hence, a collection of amended acts should, in principle, be convertible to a Git repository.
The existing systems that cost heavy money probably already support something like this. But it still would be awesome to be able to do `git bisect` or `git log -S` on such a repo.