Updated on May 17 at 3:52 p.m. ET
For the country's only test run of the 2020 census, leaders in Rhode Island's Providence County are struggling to drum up participation among one of the hardest-to-count populations in the U.S.: unauthorized immigrants.
The U.S. Constitution requires a head count of every person living in the U.S. every 10 years. The Census Bureau has sent multiple mailings and fanned out close to 1,000 door knockers across Providence County to practice making a complete tally in preparation for 2020.