Kirsten Gillibrand made Joe Biden answer for a past op-ed on women in the workplace.Jim Watson / AFP /Getty

Kirsten Gillibrand knew her moment had arrived. The CNN moderators of tonight’s Democratic presidential debate had asked a question about fining companies that don’t fix pay inequities between men and women. When it was her turn to answer, the senator from New York turned to former Vice President Joe Biden and effectively accused him of being sexist.

Years ago, Biden opposed a proposed expansion to the child tax credit. According to Gillibrand, Biden argued that “women working outside the home would ‘create the deterioration of family,’” and that “women who were working outside the home were ‘avoiding responsibility.’” She had always been a working woman, Gillibrand said, and the primary income-earner for her family. She demanded an explanation.

“That was a long time ago,” Biden replied. He said he voted against the measure because he had opposed an expanded credit for high earners, but wanted to see a higher child tax credit now. “I support making sure that every single solitary person needing child care gets an $8,000 tax credit,” he said, claiming that would allow 700,000 women to reenter the workplace.

Gillibrand didn’t yield. This attack was planned: Days before the debate, she started alluding to an unnamed opponent in the presidential race who opposed women working outside the home. “Mr. Vice President,” she said, “you didn’t answer my question. What did you mean when you said, when a woman works outside the home, it’s resulting in ‘the deterioration of family’?”

Biden hit back. “I wrote the Violence Against Women Act,” he said, citing a number of other legislative efforts he has worked on over the years to promote women’s advancement. Gillibrand had applauded him in the past, he said: “I don’t know what happened, except you’re running for president.”

Biden had a point. Although Gillibrand was trying to intimate that Biden wasn’t a good-faith supporter of women, her own Twitter feed betrays her. “Thank you VP Biden,” she wrote in October 2016, “for your unwavering commitment to combating violence against women!” There’s even a selfie.

While this attack might not have been totally airtight, Gillibrand was going after one of Biden’s major perceived weaknesses: His record as a moderate senator, lasting through years during which the public consensus on women’s issues shifted radically, is not in step with today’s Democratic voters. Earlier this year, Gillibrand led the attack against Biden’s longtime support for the Hyde Amendment, which prohibits federal funding for most abortion procedures. (Under pressure, Biden recently reversed his stance.)

Progressive women voters have been key players in mobilization efforts against President Donald Trump, whom they see as dangerously sexist. Tonight Gillibrand tried to paint Biden as similarly regressive. This time, her attack didn’t work so well. But this likely won’t be the last time Biden has to defend his record on women’s issues.

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