Restrictions On Deployed U.S. Troop Data Could Put 2020 Census 'At Risk'

New security measures at the Department of Defense that limit the release of military records about U.S. troops deployed abroad could put the accuracy of the 2020 census "at risk," according to a newly released internal Census Bureau document.

"This new guidance places us in jeopardy of not having the information necessary to count those who are deployed overseas in the communities in which they live," Census Bureau officials wrote in a Jan. 14 memo, which was prepared for Deputy Secretary of Commerce Karen Dunn Kelley.

The document was provided to NPR by attorneys for the NAACP and its local affiliates in Connecticut and Boston who filed a Freedom of Information Act lawsuit against the Commerce Department, which oversees the Census Bureau.

Counting deployed troops as residents of the stateside military installations where they're usually stationed is expected to be one of the major changes for next year's national head count.

Troops temporarily deployed to war zones and other dangerous locations make up 15 percent of all overseas service members — most of whom are stationed abroad — according to the Census Bureau memo. How this relatively small group is counted for the census, however, can have an outsize impact on how political representation is reapportioned among the states after 2020.