Kamala Harris and Joe Biden aren’t done sorting out the fallout from her lightning rod moment at last week’s Democratic debate, when the senator criticized the former vice president for his record on school busing.

The attack sent Biden reeling and solidified Harris’s ascent into the 2020 presidential field’s top tier. Harris successfully portrayed Biden as out of touch with the current Democratic Party, but after her viral moment, she is also being asked to go on the record about how she would handle busing in the current era.

At a recent campaign event in Iowa, Harris said that while federally mandated busing was necessary to integrate schools in the 1960s and ’70s, she didn’t think it was necessary now, because she no longer sees state or local opposition to integration. In fact, she said she believed it was a decision that should be left up to local school districts and municipalities, rather than the federal government.

“I think of busing as being in the toolbox of what is available and what can be used for the goal of desegregating America’s schools,” Harris said. “I believe that any tool that is in the toolbox should be considered by a school district.”

Here’s Harris’s full answer when she was asked to clarify her stance by the press, per the Washington Post’s Chelsea Janes:

Do we need to do a quick lesson in history? Which is that there were forces and individuals and supposed leaders in our country who actively worked against the integration of schools based on race. That is what was happening at that time. That’s why busing was mandatory at that time. Thankfully, fast forward to today, we don’t have that challenge. But we have other challenges that need to be addressed. We need to talk about and understand that what was going on in the 1960s, 1970s was that there was institutionalized and legal apparatus in place and forces that were literally working against integration of the schools in our country. Thankfully, that is not the case today. Thankfully today, it is very rare that we require the courts or federal government to intervene where other governments are opposed to integration. But there are still issues of segregation in our schools today. So for local school districts, for municipalities, I am in favor of whatever they need to do work on integration based on race. But thankfully we don’t see what we saw then. I think it’s very important for us to be clear on history, and frankly I think the Vice President has yet to agree that his position on the kind of busing that took place when I was bused to school was wrong.

For contrast, here’s what Harris said to Biden in her initial statement during the NBC debate:

You also worked with [those segregationist senators] to oppose busing. And there was a little girl in California who was part of the second class to integrate her public schools and she was bussed to school every day. And that little girl was me. So I will tell you that on this subject, it cannot be an intellectual debate among Democrats. We have to take it seriously. We have to act swiftly.

Former Obama adviser David Axelrod mused that Harris sounded like she was adopting a position that was more like Biden’s stance in the debate. And the Biden campaign quickly went back on offense, hitting Harris for her latest remarks.

“It’s disappointing that Senator Harris chose to distort Vice President Biden’s position on busing — particularly now that she is tying herself in knots trying not to answer the very question she posed to him!” Biden deputy campaign manager Kate Bedingfield tweeted.

While Harris wasn’t specifically asked to clarify her stance on busing at the debate, her repeated challenges to Biden on why he didn’t support federally mandated busing in the 1970s made it seem like she supported it — then and now. But her answer on Wednesday was a little more complicated: While she thinks busing was necessary in the 1970s, she doesn’t believe it’s necessary now.

Harris’s debate performance, particularly the way she pinned Biden on his complicated record on racial issues, helped propel her campaign forward. But clarifying her current-day stance on the topic is proving to be trickier.

Why busing and segregation have become such big topics in the 2020 race

The debate around busing in the 2020 campaign is more about Biden’s record than about busing itself. Biden, who entered the race as the Democratic frontrunner (a standing that has grown weaker, but not evaporated, since NBC’s June 27 debate), also entered with a very long voting record from his years in the Senate to probe, stretching from 1973 to 2009.

That voting record has provided fodder for attacks from many of Biden’s Democratic rivals, on a wide array of issues. Harris and fellow 2020 Democrat Sen. Cory Booker (D-NJ) — the two black candidates running — have homed in on Biden’s votes on racial issues, specifically his vote for a bill that made it more difficult for the federal government to enforce court-ordered busing mandates. In the 1960s and ’70s, federally ordered busing was a mechanism to desegregate schools by busing minority children to predominantly white schools and vice versa.

Segregation and busing are not nearly as big an issue today as they were in the middle of the civil rights era (although there’s data to suggest progress on desegregation has actually stalled in recent years).

But as Vox’s P.R. Lockhart wrote, “These critiques of Biden are clearly intended to make a broader point: that the former vice president, in continuing to defend his stance on busing, is out of step with the current Democratic electorate on issues of race and fighting racism. And that could be an issue for many of the black voters Biden is counting on for support.”

In an interview with CNN’s Chris Cuomo, Biden claimed his record on busing was taken out of context, and tried to draw a parallel between his and Harris’s stances on busing.

“This whole thing about race and busing, I think that if you take a look, our positions aren’t any different, as we’re finding out,” Biden said. “Look at my record.”

Joe Biden defends his record on desegregation busing: “It’s so easy to go back 30, 40, 50 years and take a context and take it completely out of context” https://t.co/i5tID1iVQV pic.twitter.com/63CjWnjQjQ — CNN Politics (@CNNPolitics) July 5, 2019

There are a few desegregation plans from 2020 candidates, as Vox’s Matt Yglesias wrote:

Harris came out in support of Murphy’s bill recently but isn’t yet a co-sponsor, according to Education Week.

She successfully cut into Biden’s lead by taking him to task for his record. But there’s still the matter of clarifying her own stance.