Vermont Sen. Bernie Sanders on Saturday said he would support a bill that revokes legal immunity for gun manufacturers, changing course after months of withering attacks from Hillary Clinton.

The bill, which is being introduced by Sen. Richard Blumenthal and Rep. Adam Schiff, would reverse a 2005 law that the NRA’s Wayne LaPierre at the time called the most significant legislation for gun owners in 20 years. Sanders voted for the 2005 bill and has taken heavy fire for it.

Sanders’ announcement comes after his chief rival Clinton accused him of weakness on gun control, and repeated criticism from Clinton he voted against the landmark Brady Bill.

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The Vermont Senator—an increasingly threatening challenger to Clinton—has said since at least October that he would be willing to reconsider his support for the 2005 bill. He has said he is in favor of protecting “mom-and-pop” gun stores from legal liability, but making sure that gun manufacturers are not immune.

“As I have said, I do want to make sure that this legislation does not negatively impact small gun stores in rural America that serve the hunting community,” Sanders said. “So I’m pleased to support the legislation and should it come up for consideration I would work to make sure it includes a provision that allows us to monitor its impact so that we may determine if it is having any unintended consequences.”

Read More: Democrats Push for Gun Control Ahead of 2016

Sanders also has pointed out that he supported the 2005 bill for including provisions that require child safety locks and prohibit armor piercing bullets. “Those were important provisions that I did support,” Sanders said.

The timing of Sanders’ reversal comes one day before a high-stakes Democratic debate in Charleston, South Carolina, the site of a devastating church shooting last year. It also narrows the policy differences between Clinton and Sanders at a key time just two weeks before the nominating contests begin.

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