Study: Immigration one of many issues that can disrupt 2020 Census

June 4 (UPI) -- When census takers tally the U.S. population next year, their final count could be off by as many as 4 million people, a new analysis said Tuesday.

The study by the Urban Institute, a Washington, D.C., social think tank, cautioned that various factors like underfunding, staffing issues, inadequate testing and a possible question about citizenship could lead to census miscalculation. The study said those issues pose "unprecedented threats" that disproportionately affect minority groups.

Urban Institute's chief methodologist Robert Santos said black and Latino households face the greatest risk of being undercounted, while some white homes are likeliest to be overcounted. The 2010 Census undercounted black homes by 2.1 percent and Latino homes by 1.5 percent.

"This all comes down to the basic concept of fairness," Santos said.

The study said an undercount could be as high as 0.27 percent in the low-risk scenario and 1.22 percent in a high-risk scenario, meaning between 900,000 and 4 million people may be missed. California could be among the most likely states to miscount, as much as nearly 2 percent -- and blacks and Latinos could be undercounted nationally by up to 3.6 percent, the institute said. Texas, with its large immigrant population, is also at risk being undercounted.

The U.S. Supreme Court has not yet decided whether the Trump administration can add the question about citizenship, which hasn't appeared on any census since 1950. Even if the controversial question isn't added, the study said the ongoing attention to immigration issues might still impact the final count.

"Current discourse about immigration could suppress participation," it said.