Is it a tax? Or is it a penalty?

In the days following the Supreme Court’s decision on President Barack Obama’s health care law, supporters and critics of the law sparred over the question of whether or not the individual mandate was a tax.

Critics of the law highlighted Obama’s shifting views of whether the mandate was a tax or a penalty (an issue we fact-checked here). On the other hand, supporters noted that if the individual mandate was actually a tax, then Mitt Romney himself had also imposed a tax when he signed a health care law as governor of Massachusetts.

Initially, a senior aide to the Mitt Romney campaign, Eric Fehrnstrom, told MSNBC that Romney “has consistently described the mandate in Massachusetts as a penalty” — a position at odds with many other Republicans in the wake of the ruling.

But then, Romney changed course in a July 4, 2012, interview with CBS News.

“Well, the Supreme Court has the final word,” Romney said. “And their final word is that Obamacare is a tax. So it’s a tax.”

We fact-checked Romney’s statement by talking to more than a dozen legal experts. Read their comments and see why we rated this statement Mostly True.