President Trump may only have seven weeks left in office, but he’s determined to do as much damage in that short time as possible, especially to immigrants and the places they live.

But at least one of his initiatives — to exclude undocumented immigrants from census counts that determine how much representation each state gets in Congress — is so plainly unconstitutional, so far outside the scope of his powers, and so absurd in practical terms that not even a Supreme Court with a conservative supermajority that includes three Trump appointees can stomach it.

That seemed to be clear when the court heard oral arguments Monday in the case of Trump v. New York, which arises from a memorandum the administration issued this summer that declared:

For the purpose of the reapportionment of Representatives following the 2020 census, it is the policy of the United States to exclude from the apportionment base aliens who are not in a lawful immigration status.

As one expert told me at the time, “The president does not have the power to decide who counts and who doesn’t. The Constitution already decided that for him.”

That would be the 14th Amendment, which states that “Representatives shall be apportioned among the several States according to their respective numbers, counting the whole number of persons in each State, excluding Indians not taxed.” There is simply no ambiguity in “the whole number of persons” — it doesn’t say citizens or adults or anything else; it says persons.

But Trump’s position — left to be argued before the court by Acting Solicitor General Jeffrey Wall — is that despite the 14th Amendment, since people just passing through a state don’t get tallied — for instance, a Portuguese tourist visiting Disneyworld at the time of the census isn’t counted as a resident of Florida — “persons” really means “inhabitants." And the president gets to unilaterally decide who’s an inhabitant and who isn’t.

Even Trump’s own appointees had trouble not laughing that idea out of court. “A lot of the historical evidence and longstanding practice really cuts against your position,” said Justice Amy Coney Barrett politely.

And even if Trump’s position weren’t so obviously unconstitutional, it suffers from a practical impediment: The whole point of the census is that it’s as precise a count as we can manage, yet there’s no way to precisely count the number of undocumented immigrants Trump wants to exclude. We have estimates from various groups that range between 10.5 and 12 million, but even the skilled demographers who come up with them are careful to note that it’s almost impossible to peg the number with certainty.

So how would Trump know how many people to subtract from each state’s population? Was he just going to guess?

Tasked with defending the indefensible, Wall argued that for now, Trump isn’t even going to try.

“Career experts at the Census Bureau confirmed with me that they still don’t know even roughly how many illegal aliens [they] will be able to identify, let alone how their number and geographic concentration may affect apportionment,” said Wall.

So Trump will try to find as many undocumented immigrants as he can — perhaps starting with those in custody awaiting deportation — and begin subtracting from there.

This is essentially the last gasp of the Trump administration’s efforts to use the census to erase undocumented immigrants and enhance the power of Republicans. As you’ll recall, they tried to add a question about citizenship on the census, knowing that its presence would discourage immigrants — documented or not — from answering. That would mean fewer immigrants counted, and fewer federal resources and representation directed toward the communities where they live.

But the administration’s effort to add the citizenship question was carried out so buffoonishly that it imploded. They repeatedly lied about what they were doing — even under oath — and eventually the Supreme Court turned back the effort, calling their rationale “contrived,” after which the administration dropped it altogether.

And once again, the administration’s sinister intentions are moderated only by their incompetence. As became clear in Monday’s oral arguments, the court could easily punt on the apportionment question, because time is running out on Trump. The Census Bureau is supposed to transmit the results to him by December 31 — a deadline it will probably fail to meet. Then, according to the law, the president passes the results on to Congress to determine apportionment.

It’s at that point that Trump wants to take his magical hurricane Sharpie and use it to cross out millions of persons — yes, persons — living in the United States. But since he probably won’t have time to do it before Joe Biden takes office on January 20, the court seems inclined to not decide the issue at all. After all, when Biden takes office no one expects him to muck with the census in this way.

It’s only a small consolation to hear the court send a clear signal that it isn’t going to give Trump what he wants. Trump’s time may be short, but until the day he leaves, he’ll be reminding us that for all the damage he did, had he gotten his way it would have been even worse.

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