The busing discussion reached a turning point during the first Democratic-primary debate, on June 27, when Harris suggested that Biden had been wrong to oppose federally mandated busing when he was a senator in the 1970s. (Biden’s position has been that busing should be required by the courts only in cases of de jure segregation rather than de facto segregation, or where communities voluntarily decide to do it.) “There was a little girl in California who was part of the second class to integrate her public schools, and she was bused to school every day,” Harris told the former vice president, her voice quaking. “That little girl was me.” It was the defining line of the debate, inspiring the creation of a T-shirt Harris’s campaign is now selling for $29.99. The point Harris was highlighting was clear: When busing would have mattered most as a method of desegregating schools, in the 1970s, Biden didn’t enthusiastically support it.

Read: The confrontation that laid bare the Democratic Party’s evolution

But since that back-and-forth, Harris has fielded daily questions about her own views on federally mandated busing—Would she support it today?—and her answers have been murky. Pressed by reporters in Iowa last week, Harris said that busing “is a tool among many that should be considered” for desegregating schools, but did not offer a firm answer as to whether she supported mandatory busing. “For local school districts, for municipalities, I am in favor of whatever they need to do to work on integration based on race,” she told reporters. A day later, Harris said that she would support mandatory busing in situations where local governments are hindering integration efforts, but that “today it is very rare that we require the courts or the federal government to intervene.”

Harris’s hedging on the issue has given Team Biden room to argue that the two see the issue similarly. “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!” tweeted Kate Bedingfield, Biden’s communications director.

Read: There’s a generational shift in the debate over busing

Other 2020 Democratic candidates, though, are more unequivocal on the issue. After reaching out to the campaigns of all 25 Democratic candidates for president, 10 responded that they support federally mandated busing: Warren; Booker; Senator Bernie Sanders of Vermont; Representative Beto O’Rourke of Texas; Representative Seth Moulton of Massachusetts; Representative Tim Ryan of Ohio; Andrew Yang; Miramar, Florida, Mayor Wayne Messam; former Senator Mike Gravel of Alaska; and former Representative Joe Sestak of Pennsylvania. Three presidential candidates—the author Marianne Williamson, Senator Michael Bennet of Colorado, and Washington Governor Jay Inslee*—said they are supportive of busing as a method of desegregating schools only in cases where the practice is voluntarily undertaken by local school districts. Former Representative John Delaney of Maryland did not voice support for busing of any kind. And 10 candidates did not respond to multiple requests for comment.