I actually looked at the constitution with respect to the census in a comment in another blog ( https://thenewneo.com/2025/08/07/trump-calls-for-new-census-that-doesnt-count-illegal-aliens/ ) Looking at the text of Article I, Section 2, Clause 3 of the US Constitution (partial) we have
Representatives and direct Taxes shall be apportioned among the several States which may be included within this Union, according to their respective Numbers, which shall be determined by adding to the whole Number of free Persons, including those bound to Service for a Term of Years, and excluding Indians not taxed, three fifths of all other Persons. The actual Enumeration shall be made within three Years after the first Meeting of the Congress of the United States, and within every subsequent Term of ten Years, in such Manner as they shall by Law direct.
So first issue is that the 3/5 clause is made moot by the 13th amendment as slavery is now forbidden, as are terms of service for a period of years . The “Indians Not Taxed” Portion has been nullified by legislative action in 1924 by the Indian Citizenship Act of 1924 so native Americans DO count towards the census. This effectively leaves us with
“according to their respective Numbers, which shall be determined by adding to the whole Number of free Persons”.
Sadly the most direct reading of that is NOT citizens but humans (actually counted/enumerated). It might be possible for the legislature to clarify the meaning to citizens (making legislative changes similar to what it did to include Native Americans). More sure would be a change in the constitutional language in the form of a constitutional amendment. A purely legislative change is likely to see judicial challenge given large blue states would get hammered by it. At present I doubt an amendment could be gotten through Congress let alone the 38 states needed for ratification. Probably worth a shot via the legislature as the Supreme Court might view that change as a clarification of the definition of Persons, analogous to the change created by the Indian Citizenship act.
With respect to the inaccuracy of the count alleged by the Trump administration the language uses the words count and enumerate. This does NOT seem to leave slop for the various estimates used in the blue cities with respect to transient and homeless populations as well as to count illegal aliens who do not directly reply to the census. The language implies that you have to actually count the people. Only people so counted, to be repetitive, count. This would be challenged but is on far stronger ground with the current Supreme Court’s tendency to being more constrained by the text.
Finally the language concerning whether you can do another census sooner than 2030 says “The actual Enumeration shall be made within three Years after the first Meeting of the Congress of the United States, and within every subsequent Term of ten Years, in such Manner as they shall by Law direct.” That implies no more than 10 years between enumerations but Congress may legislate when within that period. So it would seem they could require an enumeration sooner, but it may take legislative action depending on the law as it exists.
Of course, I am NOT a lawyer, nor do I play one on TV, so this and $2.50 will get you a cup of coffee (maybe). This particular idea of restricting the redistricting to be based on citizens (or similar) seems like a win. It also seems like what the founders intended as the purpose of redistricting is to avoid rotten boroughs, as seen in 17th-century England and trying to keep representation in line with citizens/population.
If Congress WERE to write an amendment to restrict the enumeration to citizens I would think that they should also go with something like the Wyoming rule (https://en.wikipedia.org/wiki/Wyoming_Rule), adding seats so that there is less of the discrepancy on representation/seat where some small states votes are disproportionate to districts in larger districts. Last I looked the Wyoming rule would require ~570 seats instead of the current 435 in the House. It is something the Left complains about A LOT and I do not think the Wyoming rule would have much effect on overall balance as the red areas get a fair addition of seats too.