Commerce Secretary Wilbur Ross testifies on Capitol Hill in June. (Manuel Balce Ceneta/AP)

PRESIDENT TRUMP has complained incessantly about rigged elections. But this, not phantom voter fraud, is what modern-day election-rigging looks like in the United States:

Commerce Secretary Wilbur Ross announced in March that he would add a new question to the 2020 Census form, asking respondents about citizenship status. At the time, he testified under oath before Congress that the Justice Department “initiated” the move to add the question in December 2017, arguing that Justice needed better information on the country’s voting-age population to better enforce the Voting Rights Act. The explanation was fishy from the start, since, as a federal judge noted this month, the Trump administration “has shown little interest in enforcing the Voting Rights Act.”

In fact, it is looking more and more as if one of the real initiators was former White House strategist and anti-immigration provocateur Stephen K. Bannon, according to emails the Commerce Department had to release last week. “Steve Bannon has asked that the Secretary talk to someone about the census,” Brooke Alexander, a Commerce Department senior adviser, wrote in an April 2017 email — well before the Justice Department asked for the change. “He could do it from the car on the way to a dinner.”

Mr. Ross was also keen well before Justice officially weighed in. He pressed the case in an email to Earl Comstock, director of the department’s Office of Policy and Strategic Planning, in May 2017. “I am mystified why nothing have [sic] been done in response to my months old request that we include the citizenship question. Why not?” Mr. Comstock replied that he would “get that in place” and wrote, “We need to work with Justice to get them to request that citizenship be added back as a census question.”

As Commerce staff apparently searched for and obtained a pretext to add the question, experts warned Mr. Ross it was a bad idea. John M. Abowd, the chief scientist and associate director for research and methodology at Commerce, wrote in a January letter that the proposal would be extremely expensive and harm the quality of the census count.

From the beginning, adding the question looked like a ruse to punish blue states. The constitutionally mandated census is supposed to count everyone in the country, citizen and noncitizen. The count determines where federal money goes and how many congressional seats and presidential electors each state gets. Mr. Trump’s anti-immigrant rhetoric was already bound to reduce response rates among immigrants. It is easy to imagine many tossing their census forms immediately after reading the citizenship question, for fear the federal government would be able to locate them. Large cities with high immigrant populations — which tend to be in blue states — would lose out.

There is now more evidence suggesting that this was the point and that Mr. Ross used his official powers over what should be a nonpartisan count to game the system for Republicans. The newly released emails also bolster the case that Mr. Ross was not truthful about how he made the decision.

As the real story emerges, Mr. Ross should strike the citizenship question from the 2020 Census form. If he does not, Congress should do it for him.