Bureau Director Steven Dill­ingham told the House Oversight Committee that he had no advance notice of President Trump’s memorandum, which directs the Commerce Department to exclude undocumented immigrants from being counted next year when Congress reapportions a decade’s division of House seats.

Census and legal experts say such an action would be illegal and unconstitutional, and several lawsuits have been filed challenging the July 21 memo.

At the hearing, which lasted more than 4 ½ hours and also included four former Census Bureau directors, several lawmakers drew connections between the memo and the administration’s unsuccessful bid to add a citizenship question to the 2020 Census, saying both were an attempt to disenfranchise immigrants and minorities.

Rep. Debbie Wasserman Schultz (D-Fla.) said it was “unbelievable” that Dillingham had no notice of the directive before it was issued.

“How do you reconcile the recent memorandum with the oath you swore to uphold?” she asked him.

“Let me explain that the Census Bureau produces statistics and data; we have no control over its uses,” Dillingham told her, prompting her to ask if the director was “just a data receptacle.”

Committee Democrats also questioned Dillingham about fears that the government has reversed its stance on a deadline extension for census data to be delivered. In April, when much of the country was shut down by the coronavirus pandemic, the bureau suspended many of its survey operations and asked for a four-month extension to deliver the data to the president.

By law, the deadline for its delivery is Dec. 31 of the census year, but because the bureau has had to postpone its door-to-door knocking by several months, several of its top officials have said it is no longer possible to meet that deadline. Census experts say the count could be compromised if the bureau is rushed to meet the December date.

In its Heroes Act, the House approved the bureau’s request for the delay, along with an additional $400 million to help with the count. A Senate bill unveiled this week asked for an additional $448 million in funding for the census but did not mention the extension.

Rep. Jimmy Gomez (D-Calif.), the committee’s vice chair, asked Dillingham if he had discussed the extension with Senate Majority Leader Mitch McConnell (R-Ky.), and Dillingham said he had not.

Gomez asked three times if Dillingham still supported the bureau’s original request for a deadline extension. When Dillingham’s responses did not address the question, Gomez cut in.

“I’m looking for yes or no,” he said. “It seems like there’s an obvious pattern that you’re not in control of the Census Bureau and that the political appointees of this administration are. You know your name will go down in history if this is the worst census ever conducted by the United States government. You’re not going to run away and say that this was only because of the Trump administration later on. You will be responsible.”

The administration last month added two high-level political appointees to the Census Bureau, eliciting criticism from Democrats in the House and Senate and raising concern that the new hires could attempt to influence the survey.

In addition to congressional apportionment, data from the 2020 Census will be used to determine state redistricting and $1.5 trillion a year in federal funding.

Last week’s memo prompted immediate lawsuits from several organizations, including one in Washington by the government watchdog group Common Cause and one in New York by the American Civil Liberties Union.

New York state filed suit Friday on behalf of a coalition of states, cities and counties and backed by 21 attorneys general nationwide. And on Tuesday, the state of California, several cities and the Los Angeles Unified School District sued Trump, Dillingham, Commerce Secretary Wilbur Ross, and the Commerce Department and Census Bureau, saying the order threatens to “seriously harm Plaintiffs . . . including by depriving them of their rightful share of congressional representatives and by depressing the 2020 Census count itself.”

Earlier in Wednesday’s hearing, the committee heard from four former Census Bureau directors who served under Presidents Richard M. Nixon, Gerald R. Ford, Jimmy Carter, Bill Clinton, George W. Bush, Barack Obama and Trump. They warned that Trump’s directive is likely to lower participation by immigrants.

“They’re afraid that the answers will be used against them, as it was unfortunately produced in the 1941 period with the Japanese Americans,” said Kenneth Prewitt, who served from 1998 to 2001. “Sixty years ago, we’re still talking about that. It cast a very long shadow over the census, and what we’re going through now will cast another very long shadow. If they are afraid that it will be used against them as a group, then they have a reason to sort of dodge it and not respond to it and hide out.”

Prewitt added that he was “very worried” that the bureau will not be able to produce an accurate count by the December deadline.

Trump’s memorandum could also affect lawsuits already underway, including one led by the Mexican American Legal Defense and Educational Fund in Greenbelt, Md., challenging an order for agencies to share citizenship data with the Census Bureau, which the president announced last year after the Supreme Court blocked the citizenship question.

Plaintiffs in that trial last week asked for and received permission to amend their complaint within three weeks.

Litigation over a version of the memo is also underway in Alabama, which has sued the Commerce Department and the Census Bureau, arguing that immigrants who are not in the United States legally should not be counted for apportionment or federal funding, even if they do fill out the census.

Even if the administration found some way to legally exclude undocumented people from the count, experts say it would be impossible to implement, noting that by law, apportionment must be based on the decennial census, which does not ask about respondents’ legal status.

Census experts on a call with reporters Tuesday said they worry the bureau will not have enough time or resources to count the 37 percent of households that have not self-responded to the survey. The experts noted that people hired by the bureau to go door to door are dropping out at a significant rate for coronavirus-related reasons.

Some have complained that although they have been issued hand sanitizer and masks, they have received little or no training on how to stay safe when going door to door.

A Census Bureau spokesperson told The Washington Post he was unable to verify how many enumerators have resigned.

Asked at the hearing about enumerators not being provided with adequate training, Dillingham said he would look into the reports.