Several states have joined President Donald Trump's deportation efforts and are taking federal reporting requirements to immigration authorities a step further -- by using their public health agencies as arms of enforcement.

North Carolina, in late April, became the latest member of a growing group of Republican-led states to require their public health agencies to flag recipients of Medicaid to the U.S. Department of Homeland Security (DHS) if their legal status is in question.

It's a trend health policy researchers expect to spread among GOP-controlled states eager to join Trump in the federal crackdown on Medicaid fraud and illegal immigration. Already, at least four states -- Indiana, Louisiana, Montana, and Wyoming -- have passed similar laws, and lawmakers in others, such as Oklahoma and Tennessee, are weighing measures. In those six states, Republicans hold a power trifecta -- both chambers of the legislature and the governor's office.

"This is an issue that is very much on the political radar right now," said Carmel Shachar, a health policy researcher at Harvard Law School.

More than 75 million people are enrolled in Medicaid, the federal and state-run public health program for people with disabilities and low incomes, or its related Children's Health Insurance Program, which provides low-cost coverage for people under 19. Immigrants without legal status are ineligible for Medicaid benefits, but a swath of noncitizens qualify, such as green-card holders, asylees, and refugees. A quarter of children in the U.S., most of them citizens, live with an immigrant.