Sen. Kamala Harris (D-CA) used Wednesday evening's Democratic primary debate to challenge former Vice President Joe Biden on his past opposition to federal abortion funding.

"On the Hyde Amendment, Vice President, where you made a decision for years to withhold resources to poor women to have access to reproductive health care, including women who were the victims of rape and incest, do you now say that you have evolved and you regret that?" asked Harris during a debate hosted by CNN August 1. 

The Hyde Amendment prohibits the use of federal funds to pay for abortion services. 

Biden supported the Hyde Amendment, both with his votes and publicly in writing and speeches, for over four decades. He reversed his position on the issue in June this year, just one day after reaffirming his support for the policy. Harris was quick to point this out during the debate. 

"Only since you've been running for president this time, [have you] said that you in some way would take that back or you didn't agree with that decision you made over many, many years and this directly impacted so many women in our country," said Harris. 

Biden responded by saying that it was "not my position" and that the rest of the Democratic primary candidates who have served in Congress have voted for the Hyde Amendment in one way or another. 

He further defended his past positions, saying that there were alternative, privately-funded programs that would assist with abortion access for low-income women. Biden also touted his past work writing legislation that would enable federal funds to be used for abortions. 

"Once I wrote the legislation making sure that every single woman would in fact have an opportunity to have healthcare paid for by the federal government--everyone--[the Hyde Amendment] could no longer stand," said Biden. 

The Affordable Care Act, which was signed into law in 2010, permits insurers to cover abortion services in their plans, as long as they are in a state that does not ban insurance coverage of abortion and that private money is used to pay for the abortions. 

Biden, who is Catholic and has frequently cited the role of his faith in his life and political career, said Wednesday that he supports "a woman's right to choose" and that it is a constitutional right that should be enshrined in federal law.

"I've supported it, I will continue to support it, and I in fact will move as president to see that Congress legislates that that is the law," he said. 

In the past, Biden has presented himself as a moderate on the issue of abortion. In an interview shortly after the 1973 Roe v. Wade decision, he refused to support unrestricted access to abortion and said that he thought the Supreme Court "went too far" in their decision. 

In 1981, he leant his name to the "Biden Amendment," which banned the use of federal funds for biomedical research involving abortion or involuntary sterilization.

In 2007, Biden described his views on abortion as "middle of the road" and said that he was against both the federal funding of abortions and the technique of partial-birth abortions. In 2012, during the vice presidential debate, Biden said he was personally pro-life. 

The 2016 Democratic Party Platform called for the repeal of the Hyde Amendment. This was the first time this plank has been included in the party platform. 

While three out of four women who undergo abortions are living in poverty, the Hyde Amendment is actually far less popular among low-income voters. A 2016 poll found that only 24% of people making under $25,000 a year said they were in favor of the public funding of abortion services, compared to 45% of people making over $75,000.

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