Update, 6pm: The Trump White House backtracked on a plan to add a citizenship question to in a press conference. Attorney General William Barr said there was no way “to implement any new decision without jeopardizing our ability to carry out the census.”

US president Donald Trump will hold a press conference this afternoon where he’s expected to announce that he is defying the Supreme Court by adding a question about citizenship to the US Census.

His threat to ignore the Supreme Court, which last month ruled the administration’s reasons for the citizenship question were suspect, has raised new concerns about whether the US is hurtling towards a constitutional crisis, and Trump’s fitness for office. That aside, on a very practical level, the Trump administration literally does not have the money to make the change that Trump wants.

Paper questionnaires for the census, which is conducted by the Department of Commerce, are already being printed by R.R. Donnelley & Sons Company, a Chicago printing company. The company got a $114 million contract to print the census in January of 2018, and said then it planned to start printing it this year. Commerce Secretary Wilbur Ross said July 2 printing of the census had started without a citizenship question.

The Congress member in control of the purse strings for the census is the House’s José Serrano, a Democrat from the Bronx. He said in no uncertain terms this week that he won’t approve funding for a new print-run of the census.

Serrano’s office said July 9 he had “no intention of allowing this flagrant waste of money.”

Because printing of the Census form without the citizenship question has now started, amending the form could potentially cost hundreds of millions of additional taxpayer dollars, in addition to untold millions of dollars for additional non-response follow-up resources next year. As Chairman of the Commerce, Justice, Science Appropriations Subcommittee, I want to make one thing clear: I have no intention of allowing this flagrant waste of money.

House speaker Nancy Pelosi reiterated Serrano’s message in a press conference this morning:

Congress, and particularly the Democratically controlled House, oversee how the White House and cabinet agencies spend money. Earlier this year, Trump resorted to an “Emergency Declaration” to divert funds from US military housing and drug-fighting to his wall on the southern border after the House wouldn’t approve the money he wanted.