Congressional Democrats are preparing to issue their first round of subpoenas to President Donald Trump’s new attorney general this week — but not on the issues that one might expect.

For months, House Democrats have threatened to subpoena Trump and top members of his inner circle on everything from the Robert Mueller investigation to Trump’s personal finances and business dealings. But one week after a summary of Mueller’s findings were released to the public, the House Oversight Committee plans to vote on Tuesday to issue subpoenas to Attorney General Barr and Commerce Secretary Wilbur Ross related to a question on the upcoming census.

On Friday, Rep. Elijah Cummings (D-MD), chair of the House Oversight Committee, wrote in a letter to Commerce Secretary Wilbur Ross that the committee “is seeking to understand the real reason that you added a citizenship question to the 2020 census.”

Cummings also accused Commerce Department officials of repeatedly withholding key documents used to justify asking census respondents to disclose their citizenship status.

Next week Cummings’s oversight panel will decide whether Principal Deputy Assistant Attorney General John Gore must testify before Congress on the issue and whether Attorney General William Barr and Commerce Secretary Wilbur Ross should be forced to hand over more details disclosing how the decision was made. If the administration officials choose to snub them once again, the Democratic-controlled panel may escalate their inquiry.

According to the Associated Press, the Commerce Department has already handed over 11,000 pages of documents pertaining to the panel’s inquiry. Ross, who first announced the addition of the citizenship question in March 2018, also testified before committee members, addressing their concerns earlier this year. Ross’s testimony maintains that the Commerce Department added the question, which hasn’t been included in the census in more than 60 years, on the request of the Justice Department to “better enforce” the Voting Rights Act of 1965.

Critics, however, say the move has a much more nefarious motive. Advocacy groups worry the line of questioning will scare immigrant communities into wrongly believing that the federal government will track them. Because the census helps determine the number of congressional seats and electoral votes allotted to each state, other skeptics believe the change to the census is politically motivated and meant to alter how congressional districts are allocated in Republicans’ favor.

The federal courts are already considering the census question

The Trump administration is already wrapped up in the federal courts over the citizenship question and the true intentions behind it. In January, a federal judge in New York barred the federal government from adding the question to the 2020 census. Now the Supreme Court will take up the issue in oral arguments that begin in April.

The lawsuit primarily centers on the allegation that the Commerce Department lied about why it really wanted to include the citizenship question. As Vox’s Dara Lind explained earlier this year, “Judge Jesse M. Furman of the Southern District of New York found that Commerce Secretary Wilbur Ross violated federal law by misleading the public,” and the repercussions of his actions could linger for decades.

It’s not just a symbolic issue. Critics are seriously concerned that adding a single citizenship question to the 2020 census could scare away millions of immigrants from filling out their mandatory surveys — throwing off the count of who’s present in America that’s used to determine congressional apportionment for the next decade, allocate federal funding for infrastructure, and serve as the basis for huge amounts of American research. A skewed census would hurt the places in America where Latinos are most likely to live — cities and blue states — fueling both the lawsuit and the suspicion that the Trump administration is engaging in deliberate subterfuge.

Cummings’s investigation now works in parallel with the courts’ attempts to root out the Commerce Department’s true intentions, meaning that one way or another, the administration may have to disclose whether the fears of skeptics ring true.