Commerce Secretary Wilbur Ross faced tough questioning Thursday from Democrats on the House Oversight Committee about whether he lied to Congress about his decision to add a citizenship question to the 2020 census.

The committee's chairman, Rep. Elijah Cummings, D-Md., asked whether Ross had been "truthful" in testifying to Congress three times last year about whether "he added the citizenship question only because of the Department of Justice requested it."

“The key question we will ask Secretary Ross today is, what was he hiding from the Congress?" Cummings said. “What’s the real reason that the Trump Administration wanted to add this unconstitutional citizenship question?"

Ross said in his opening statement that before he decided to add the question, he learned that the Justice Department might want it included.

“I instructed staff to follow up with DOJ for a written statement confirming whether or not DOJ was going to ask for reinstatement of the question," Ross said. "I wanted to make sure that we had enough time to adequately consider any formal request that DOJ might make.”

Ross' highly anticipated appearance before the committee on Thursday comes just days after a second federal judge said he had violated federal law and the Constitution by hastily adding the question to the survey.

Democratic members repeatedly attempted to press Ross about when exactly he made the decision to add the question, which they insisted would result in an undercount and could thus affect the dispersal of billions in federal aid.

Republicans sharply criticized the Democrats, arguing that the census has asked the citizenship question on supplemental forms in the past and Ross did nothing wrong by adding it to the 2020 census.

Ross argued that, ultimately, the Justice Department made a formal request in December 2017 for the Census Bureau to reinstate the citizenship question on the census "for use in Voting Rights Act enforcement," prompting the Census Bureau to initiate "a legal, policy, and programmatic review process to consider alternate means of meeting DOJ’s request.”

Ross testified before the House Ways and Means Committee last March that the question was added at his direction after he received the DOJ request. But documents released as a part of a multistate lawsuit against Ross showed that the secretary had inquired about adding the question much earlier.

Freshman Democratic Rep. Alexandria Oscasio-Cortez, D-N.Y., tried to pin Ross down on his rationale. She pointed to memos, emails and phone calls that were revealed in the ongoing litigation that show Ross spoke with former White House chief strategist Steve Bannon and former Kansas secretary of state Kris Kobach, who advised Trump’s transition team, about adding the question.

“Did you speak to Mr. Kobach about his decision on the citizenship question?” she asked.

Ross acknowledged that he did speak with Kobach but said he didn't follow through with his suggestions.

She then suggested that Ross violated federal law by not advising Congress about his decision to add the question, asserting that the question is “materially different,” containing more detail than the one that was asked last time the census officially included the question, in 1950.

Let our news meet your inbox. The news and stories that matters, delivered weekday mornings. This site is protected by recaptcha

Ross, however, said that his agency had in fact “complied with all the regulations.”

Republicans excoriated Democrats, accusing them of politicizing the process and defended the decision to add the question to the census. They also attempted to adjourn the hearing, arguing that it could influence a decision by the Supreme Court, which plans to take up the issue next month.

“I mean, for the life of me, I do not know why the Democrats don’t want to know how many citizens are in the United States of America," Rep. Jim Jordan of Ohio, the ranking Republican, said. “But for some reason, they are focused on this question. Maybe it’s politics. It seems clear to me we are having the hearing today for that reason. The majority insists on politicizing the 2020 census.”

Mark Meadows, R-N.C., later added: “Many of the questions that you will receive today have nothing to do with accurately counting the number of people that are here in the United States of America. It has everything to do with politics. And everything to do with trying to make sure that one particular message comes across.”

Ross also assured Rep. Virginia Foxx, R-N.C., that the data collected about citizenship would not be used in immigration enforcement.

"The census question will not ask about legal status of the respondent," he said. "It simply asks about the factual status, citizen or not, and some questions about where they came from. There's nothing in the census data that can be used by enforcement authorities for immigration or for any other purpose."

Republicans on the committee also raised concerns about the hearing being used in the upcoming Supreme Court case that will decide whether asking the question is unconstitutional.

“To think that this isn’t going to come up in oral arguments is actually folly,” Rep. Kelly Armstrong, R-N.D., said. “What is not appropriate is weaponizing this congressional hearing to effectively create an end-run around the Supreme Court staying the deposition of Secretary Ross.”

Rep. William Clay, D-Mo., who chaired the congressional panel overseeing the 2010 census, grilled Ross over his past statements on who initiated the inquiry into the citizenship question.

Clay noted that in Ross' three past appearances before Congress in 2017, he said the Justice Department initiated the request in December of that year. However, Clay pointed to a May 2017 email from Ross to aides in which the secretary said, “I am mystified why nothing have been done in response to my months old request that we include the citizenship question. We need to work with Justice to get them to request that citizenship be added back as a census question."

Ross, however, explained that he was frustrated that he did not receive a definitive answer about whether or not department would “formally request” the question because he assumed the agency had plans about reinstating it. He continued to maintain the basis for his decision was the official memo released in March 2018 in which he said the DOJ requested the request be added because it was necessary to enforce the Voting Rights Act.

Clay then blasted Ross, saying that his past statements were meant to mislead lawmakers and the public.

“Mr. Secretary, you lied to Congress, you misled the American people, and you are complicit in the Trump administration’s intent to suppress the growing political power of the non-white population,” Clay said. “You have already done great harm to the census in 2020, and you have zero credibility, and you should, in my opinion, resign.”

Rep. Debbie Wasserman Schultz, D-Fla., questioned Ross about an email that he sent in August 2017 in which he suggested that someone within the administration strongly opposed adding the question and said he wanted to speak with then-Attorney General Jeff Sessions about adding it.

Ross said he did not recall the email or any other discussions with Sessions, adding that any conversation he had with the attorney general was confidential.

“You are just continuing to stonewall,” Wasserman Schultz said. “You don’t know the answer? Is that because you don’t remember the conversation? On the phone? You don’t remember sending your own email that’s before your very eyes?”

Ross later added, “Anybody who has followed recent events knows that Attorney General Sessions was not someone I or anyone else could bully into any decision. … The official document from the Department of Justice reflects their view.”

Jordan slammed Democrats for opposing adding the citizenship question to the standard census given that it has appeared on the supplemental American Community Survey, which asks more detailed questions to a smaller portion of the population.

“The only people opposing it are Democrats in Washington, D.C.," he told Ross. "You’re just doing as best you can, and you have a formal directive from the Department of Justice saying put the question on the census.”

“Imagine that," Jordan said. "You went above and beyond what, frankly, I think you had to do, but that’s how you did it.”

At the conclusion of the hearing, Cummings thanked Ross for appearing after weeks of haggling between the committee and the Commerce Department, but said he remained unconvinced about Ross's sworn testimony.

“I’ve been thinking about how you were going to get around some of the issues that have been raised with regard to whether your testimony was consistent and whether this came from DOJ or this originated with you,” Cummings said. “I’ve listened, Mr. Secretary, and I tell you, I’m not totally convinced that this did not come directly from Mr. Bannon and it did not come from the very beginning.”

Cummings requested that Ross provide additional documents and written answers to questions that went unanswered during the hearing, or else.

"Now, if you don’t agree with this, you will basically be forcing us to consider a subpoena," he said.