For a couple of years during Covid, the Democratic majority in the House allowed proxy votes - votes cast by members present on behalf of absent members - to count towards a quorum for doing business.
Here's the Constitutional issue. The Constitution explicitly authorizes each chamber to determine its own rules of procedure. But it also explicitly requires a majority for conducting business.
So can the House devise a rule that manipulates the meaning of the word "majority"?
They clearly had a majority of members' votes available, but apparently at times only a minority of members' bodies present.
Is all the legislation that was passed that way illegitimate, having not been passed in a constitutionally allowable manner?
Of course most of the hoopla in this case is about is about the evil of a judge striking down a desirable law. Americans, on the whole, don't care at all about constitutional requirements.