Hailing what he called a "historic moment," Gov. Bill Lee on Monday signed the so-called heartbeat bill to sharply curb when abortions can take place in Tennessee.
The legislation, passed by lawmakers in the waning hours of last month's session in Nashville, faced immediate opposition from several groups who say it's unconstitutional.
Moments after Lee signed the bill, a federal judge in Nashville issued a temporary restraining order halting it.
The fight over the law may go as far as the U.S. Supreme Court.
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Lee, a staunch conservative when it comes to abortion access, posted his signing of the law live on Facebook.
"It's our responsibility to protect the most vulnerable in our community, and certainly the most vulnerable in Tennessee includes the unborn," he said.
The legislation bans abortions once a fetal heartbeat is detected, which is as early as six weeks. It also criminalizes medical professionals who perform an abortion after those six weeks.
The bill also requires an ultrasound before an abortion and makes it illegal for a woman to have an abortion because of the child's sex, race, or potential for down syndrome.
While there is an exception for medical emergencies, there are no exceptions in the bill for women who are victims of rape or incest.
Similar legislation is being tested in other states including Missouri, where a court has blocked its imposition. The same appears likely in Tennessee.
Lee thanked Republican legislative leaders who helped push the bill through. It was among the few documents to see passage that didn't address the current budget or virus crisis.
Democrats quickly spoke out against Lee's move Monday afternoon.
“This clearly unconstitutional affront to a woman’s right to choose has no exception for rape, incest or juveniles in the custody of the Department of Children’s Services and could lead to the return of back-alley abortions to the state. This bill was crammed through the legislature in the dead of night last month with no public input while we were in session to pass the state’s budget," state Rep. Mike Stewart, the House Democratic Caucus chair, said in a statement.
Immediately upon passage June 19, the American Civil Liberties Union announced that it, Planned Parenthood and the Center for Reproductive Rights had filed an emergency lawsuit in Nashville seeking to block the heartbeat bill. A federal judge said at the time Lee first would have to sign it before the court could consider acting any further.