For a second time this month, a leading Democratic presidential candidate was grilled by late-night host Stephen Colbert. And for a second time this month, the candidate didn’t really give him the answer to what he was asking.

Two weeks after Colbert resisted former vice president Joe Biden’s attempts to downplay his false war-hero story, the comedian this week gave Sen. Elizabeth Warren (Mass.) a talking-to over a question she refuses to answer. It’s about whether she would raise middle-class taxes to pay for her expensive Medicare-for-all health-care program. At each of the last two debates, Warren has been pressed on this and declined to directly answer. Each time, she has pivoted to how the middle class would see its overall costs (including taxes and health-care expenditures) decline.

So Colbert tried again, and he even volunteered an argument for her. Here’s the exchange:

COLBERT: You keep being asked in the debates: How are you going to pay for it? Are you going to raise the middle-class taxes? [PAUSE] How are you going to pay for it? Are you going to raise the middle-class taxes?
WARREN: So, here’s how we’re going to do this. Costs are going to go up for the wealthiest Americans, for big corporations —
COLBERT: Taxes is what you mean by costs?
WARREN: Yeah. And hard-working middle-class families are going to see their costs go down. And —
COLBERT: But will their taxes go up?
WARREN: But, here’s the thing —
COLBERT: But, here’s the thing: I’ve listened to these answers a few times before, and I just want to make a parallel suggestion for you about how you might defend the taxes that perhaps you’re not mentioning in your sentence, [which] is that: Isn’t Medicare-for-all like public school? There might be taxes for it, but you certainly save a lot of money on sending your kids to school, and do you want to live in a world where kids aren’t educated. Do you want to live in a world where your fellow citizens are dying, even if it costs a little bit of money?
WARREN: So, I accept your point and I believe in your point. Health care is a basic human right. We fight for basic human rights, and that’s Medicare-for-all. Everyone gets covered. But here’s how I look at it.

Warren then spoke for about two minutes, during which she never addressed the question about whether middle-class taxes would go up.

First off, it’s valid for Warren to want to refocus the issue on total costs rather than just taxes. If you are spending $4,000 on health-care costs right now, paying an extra $1,000 or $2,000 in taxes, getting those health-care costs wiped out would be a pretty good deal (provided the care is as good). This is why Warren supporters hate this question. They view it as an unfair attempt to give Republicans a talking point that “Elizabeth Warren is going to raise middle-class taxes!” when, in fact, people’s total costs would go down.

But there are a lot of assumptions built into that. The first is that they would all wind up in net-positive territory. Studies have shown most people under a single-payer system would wind up paying less in overall costs, but that wouldn’t necessarily be consistent across the population.

A 2018 Rand study for New York, for example, showed that such a system in that state would reduce average costs for every income group up to the 75th to 90th percentile. But it added that even a little bit of tax avoidance by the wealthiest citizens would mean “potentially increasing the burden on middle- and lower-income residents” and that “the results depend on assumptions about uncertain factors.”

As NPR reported on this question, whether a family would wind up in net-positive territory would also depend on how much it is currently paying for health care — for example, if it pays little because of a generous employer or if it doesn’t have a plan. The other question is whether the proposals put forward by candidates such as Warren would completely fund the program or whether more tax revenue would be needed.

Even considering all that, Colbert’s point is worth lifting up: Why not just level with people about it? Why not say taxes will go up but total costs should go down when you factor in everything, and that it’s about the common good? Why not make sure people fully understand how this will work?

That seems to be effectively what Warren is saying. But you could (perhaps incorrectly) interpret her non-answer as suggesting that all of the tax burden would be borne by the wealthy rather than the middle class. Even if you stand to pay less in total costs, the amount your taxes change or go up does matter, especially if you believe there would be a trade-off in quality when the government is in charge of health care.

Warren’s non-answer also stands in contrast to her fellow Medicare-for-all supporter on the debate stage, Sen. Bernie Sanders (I-Vt.). His page explaining the funding for his Medicare-for-all program includes a 4 percent “income-based premium” for the average family of four earning $50,000 a year — while, of course, emphasizing that they would come out ahead.

“People who have health care under Medicare-for-all will have no premiums, no deductibles, no co-payments, no out-of-pocket expenses,” Sanders said at June’s debate. “Yes, they will pay more in taxes but less in health care.”

Warren is making a play in this race as the personable, accessible candidate, as well as the candidate who has a plan for everything — bold, radical ideas. But how she would pay for this massive expansion of government is still murky, including on this key point.

“Senator Warren is known for being straightforward and was extremely evasive when asked that question, and we’ve seen that repeatedly,” South Bend, Ind., Mayor Pete Buttigieg, a fellow Democratic presidential candidate, said Thursday on CNN. He wasn’t wrong.