Mitt Romney says he has no love for ObamaCare's individual mandate to purchase health insurance. But he continues to defend the strikingly similar state-level mandate he signed into law as governor of Massachusetts. The reason, he's often said, is that he wanted to encourage "personal responsibility." Here's Romney from over the summer, via ThinkProgress:

I will repeal ObamaCare, but the Massachusetts plan was right for Massachusetts. Personal responsibility was the way to go. People in Massachusetts favor the plan 3 to 1. If they don’t like it they can get rid of it. I like what we did in our state. It won’t work in Mississippi. That’s what’s great about a state plan. Obama is trying to impose on nation. I like personal responsibility and I like freedom. 

Let's leave aside the question of whether it really counts as personal responsibility when state authorities require you to do something. Romney claims he was trying to address the so-called "free-rider problem" in health care; every year, some number of uninsured individuals showed up at emergency rooms or other health care facilities, got care, and never paid for it. This is what's known as uncompensated care. It doesn't go entirely uncompensated, however. State and federal officials pay for it through safety net funds. And one of the reasons that the federal government approved a Medicaid waiver to help pay Romney's health care overhaul was that increasing the number of Bay State residents with health insurance was supposed to rid the state of the need for safety net spending. 

But it hasn't exactly worked out that way, and that's complicating the efforts to extend the state's Medicaid waiver. Via Politico:

Now CMS and Massachusetts face pressure to phase out some of the safety net funds. More than 98 percent of residents are now insured, according to the state’s own figures, but demand for care at the safety net hospitals and clinics is on the rise.

“The underlying principle … was that as more people became insured through new health reform options, the funds needed for uncompensated care necessarily would decline,” according to a 2009 report on the Massachusetts waiver.

However, the August study showed that community health centers and safety net hospitals saw an increased demand — although not all the care was uncompensated — during the first three years of Massachusetts health reform.

That experience spells out a larger lesson for implementation of the Affordable Care Act because of how closely the federal law follows the Massachusetts model, said a Massachusetts health policy source. The ACA scales back funding for disproportionate share hospitals — a special designation for hospitals with significantly higher shares of impoverished patients — while Medicaid is expected to absorb 16 million more people after 2014.

“The assumption that near-universal coverage will eliminate the need for extra financial help for safety net institutions is false, and Massachusetts provides the proof,” the health policy consultant said.

Indeed, uncompensated care in the state's hospital system rose five percent between 2008 and 2009. The following year, it rose 15 percent. The state has already spent hundreds of millions expanding insurance coverage in hopes of solving the uncompensated care problem. In the medium to long run, it may spend billions more. But the problem is still growing. And for that, Mitt Romney is personally responsible.