"That is a damning non-answer," Tim Walz responded in the key moment.
In one of the most notable exchanges of the vice presidential debate, Republican candidate JD Vance refused to say former President Donald Trump lost the 2020 election and downplayed the events of Jan. 6, 2021, when a pro-Trump mob stormed the U.S. Capitol to try to stop the ceremonial certification of the results.
The Ohio senator also declined to rule out challenging the outcome of the 2024 race, even if votes were certified by every state leader as legitimate.
Minnesota Democratic Gov. Tim Walz, Vice President Kamala Harris' running mate, expressed exasperation and disbelief. He said such denialism had to stop because it was "tearing our country apart."
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The topic of democracy, a top issue for many voters this cycle, came up near the end of the 90-minute debate hosted by CBS News in New York City.
Moderator Norah O'Donnell, noting there were no findings of widespread fraud in 2020, asked Vance about his past comment that he would not have certified the election if he had been vice president and instead would have asked states to submit alternate slate of electors.
"That has been called unconstitutional and illegal," O'Donnell said. "Would you, again, seek to challenge this year's election results, even if every governor certifies the results?"
Vance first sidestepped the question by saying he was "focused on the future" and criticized Harris, who he later claimed was the real "threat to democracy" as he accused her of censorship.
When he did address the question, he said: "Look, what President Trump has said is that there were problems in 2020, and my own belief is that we should fight about those issues, debate those issues peacefully in the public square."
"And that's all I've said, and that's all that Donald Trump has said," Vance continued, even though Trump is criminally accused of trying to overturn the election. "Remember, he said that on Jan. 6, the protesters ought to protest peacefully, and on Jan. 20 what happened? Joe Biden became the president, Donald Trump left the White House and now, of course, unfortunately, we have all of the negative policies that have come from the Harris-Biden administration."
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Walz called those comments "troubling" and said he was concerned about Trump's recent threats to jail political opponents and his efforts to cast doubt on this year's outcome.
"Here we are, four years later, in the same boat," Walz said. "I will tell you, that when this is over, we need to shake hands, this election, and the winner needs to be the winner. This has got to stop. It's tearing our country apart."
The two, in a departure from the civil tone of the night, got into a tense back-and-forth on the issue.
Vance tried to cast election denialism as an issue for both parties, trying to equate Trump's actions to Hillary Clinton's complaints about the 2016 election (but only after she conceded).
"Hillary Clinton, in 2016, said that Donald Trump had the election stolen by Vladimir Putin because the Russians bought, like, $500,000 worth of Facebook ads," Vance said.
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"January 6 was not Facebook ads," Walz said, hammering him for casting Jan. 6 as "peaceful" given the violence and deaths.
That day, which began with a speech by Trump at the Ellipse in which he told attendees to march "peacefully and patriotically" to the Capitol, culminated in approximately 140 law enforcement officers being injured, more than a thousand people being charged and cost millions of dollars damage.
In the months leading up to Jan. 6, Trump spread falsehoods about the 2020 election being "rigged" and "stolen" by Democrats. At the Ellipse, he continued the incendiary language and proclaimed, "If you don't fight like hell, you're not going to have a country anymore."
Toward the end of Tuesday's debate, Walz turned toward Vance and pressed him directly: "Did he lose the 2020 election?"
"Tim, I'm focused on the future," Vance responded.
"That is a damning non-answer," Walz shot back.
He also invoked former Vice President Mike Pence, saying the reason he wasn't on the debate stage was because of his decision to carry out the certification of the 2020 results against Trump's wishes.
"America, I think you've got a really clear choice," Walz said, "of who's going to honor that democracy and who's going to honor Donald Trump."
Trump also refused to accept that he lost the 2020 election during the ABC News presidential debate on Sept. 10.
When confronted with own recent remarks that he "lost by a whisker," Trump doubled down. "I said that?" he responded.
"Are you now acknowledging that you lost in 2020?" ABC News moderator David Muir asked.
"No, I don't acknowledge that at all," he said. "That was said sarcastically."
Trump has pleaded not guilty and denies any wrongdoing as he faces federal and state charges for his efforts to overturn his election.