IN ABRAHAM MASLOW’S hierarchy of needs—a well-known theory in psychology—people worry about their health only after they have secured food and shelter. In America, the opposite can be true. Those without health insurance are at greater risk of losing their homes. That is the conclusion of recent research in the American Journal of Public Health. It finds that, in states with less access to Medicaid, a low-cost health-care scheme for the poor, rates of eviction are higher than in states where it more freely available.

The research makes use of a natural experiment that followed the passage of the Affordable Care Act of 2010, better known as Obamacare. One of the pillars of Barack Obama’s health-care reform was an expansion of Medicaid to adults earning up to 138% of the federal poverty level. But in 2012 the Supreme Court ruled that the federal government could not force states to take part. Many with Republican governors or legislatures opted out. The expansion of coverage in some states but not others has allowed researchers to study the programme’s influence on measures of health, poverty and financial well-being.

One such study, by Naomi Zewde, Erica Eliason and Heidi Allen of Columbia University, and Tal Gross of Boston University, examines Medicaid’s effect on eviction rates. Using data from the Eviction Lab, a research group at Princeton University, the authors found that, between 2013 and 2016, evictions in states that expanded Medicaid fell from 17 to 14 per 1,000 renter-occupied households. States that chose not to expand the programme saw no such change (see chart). After controlling for population and other variables, the authors estimated that Medicaid expansion was associated with 1.16 fewer evictions per 1,000 households per year (ie, a cut of around 7% in the eviction rate).

This ought to be no surprise. The vast majority of evictions in America happen because tenants cannot pay the rent. Given that Medicaid covers nearly all health-care costs, the newly enrolled have more money for other things, including housing.

One-sixth of poor Americans lack health-care coverage. As the 2020 presidential campaign intensifies, the three leading Democratic presidential contenders—Elizabeth Warren, Joe Biden and Bernie Sanders—all support extending Medicaid even further than Mr Obama had attempted. Even if one of them wins, though, their policy is likely to run into the same obstacle: the resistance of some Republican-controlled states to expanding Medicaid. If so, the chances are that red states will continue to boast some of the highest eviction rates in America.