Sen. J.D. Vance scored style points at the vice presidential debate Tuesday evening, but he also had one line that stuck out in the minds of his critics.

Donald Trump’s choice for V.P. was smooth in his delivery but appeared flustered at one point in the debate, during his discussion of the Haitian immigrants living in Springfield, Ohio.

The moment occurred when Margaret Brennan of CBS News pointed out to the audience that those immigrants in fact have legal status.

“The rules were that you guys weren’t going to fact check!” the Republican contender shouted.

The moment was highlighted by Vice President Kamala Harris’ campaign, which posted, “Still thinking about this” along with a photo of the moderator’s explanatory comment to the audience, and Vance’s defensive remark.

Former Trump campaign aide A.J. Delgado responded to that, saying, “This was so so so bad.”

“OMG, just let them do the fact-check. You look 10X’s worse saying, ‘Waaaa! You guys were going to let me lie! No fair!’ Ooomph, terrible gaffe,” she wrote. “BTW, CBS wasn’t ‘fact-checking’ Vance. It was clarifying for viewers a question the moderators themselves asked. The moderator was not getting ‘in between’ the two and fact-checking one. He doesn’t even know what a fact-check is or how it works.”

Dana Milbank of the Washington Post also drew attention to that moment, saying, Vance “lodged a whiny protest.”

“It was a lie on top of another lie, supplemented by a pair of other lies, in support of an even bigger lie,” Milbank wrote. “There was no ‘rule’ against fact-checking. And Vance had just told a whopper. He had alleged that, in Springfield, Ohio, ‘you’ve got schools that are overwhelmed, you’ve got hospitals that are overwhelmed, you have got housing that is totally unaffordable because we brought in millions of illegal immigrants.'”

Milbank continued:

“There is no ‘open border,’ Kamala Harris isn’t the president, and the thousands of Haitian migrants to which Vance was referring have legal status, which Brennan had accurately pointed out. But Vance claimed that ‘what’s actually going on’ was that the Haitian migrants are there as part of ‘the facilitation of illegal immigration’ — and he kept going until the moderators shut off the candidates’ microphones.”

Read the full piece here.