Gov. Brian Kemp is set to sign the anti-abortion “heartbeat” bill into law on Tuesday, a move that will set in motion a drawn-out legal battle that the Republican and other supporters hope lands in the U.S. Supreme Court.

The governor was long expected to sign House Bill 481, which would ban most abortions after six weeks of pregnancy, making it one of the nation's strictest laws of its kind. The bill will be inked at 10 a.m. Tuesday in the governor's ceremonial office at the state Capitol.

The governor's office on Monday confirmed the timing of the signing of the bill, which Kemp said upholds his promise to enact the "toughest abortion bill in the country." After initially backing a weaker measure, Kemp endorsed the "heartbeat" bill in March and lobbied lawmakers to approve it.

Democrats, medical lobbies and civil rights organizations have forcefully opposed the measure, warning it could force women to take dangerous steps to seek abortions and cost millions in tax dollars to defend. They also say it could jeopardize Georgia's pro-business reputation.

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Kemp and other Republicans made the heartbeat measure a leading priority of the legislative session, calling it their best option to preserve the sanctity of life. With two new conservative justices on the Supreme Court, they see an opening to test the 1973 Roe v. Wade ruling that legalized abortion.

The new legislation would outlaw most abortions once a doctor detects a heartbeat in the womb – which is usually about six weeks into a pregnancy and before most women know they are pregnant.

Doctors who oppose the legislation, however, say what appears to be a heartbeat at six weeks signals the practice motions of developing tissues that could not on their own power a fetus without the mother.

Georgia law now bans abortions after 20 weeks of pregnancy.

March 14, 2019 - Atlanta, Ga: Women with the Handmaid Coalition of Georgia stand in the hallways outside of room 450 protesting HB481 where there was a committee meeting about the bill at the Georgia Capitol Thursday, March 14, 2019 in Atlanta. (JASON GETZ/SPECIAL TO THE AJC)

Credit: Jason Getz

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Credit: Jason Getz

A certain legal challenge

HB 481 would not take effect until the beginning of next year, so the timing of a legal challenge is not yet certain. But the ACLU and other critics have vowed they will bring a lawsuit targeting the legislation -- and promised electoral payback as well.

“Signing this bill is not the end of the HB 481 fight,” said state Sen. Jen Jordan, D-Atlanta, “it marks beginning of women in this state working to take their place at political table because we’re finished being on the menu.”

Similar measures have been introduced in at least 15 states and three - in Kentucky, Mississippi and Ohio – have been signed into law. A federal judge has already blocked Kentucky's version, and other courts struck down similar laws that were recently enacted in Iowa and North Dakota.

Like some other versions, Georgia’s law includes exceptions for incest, rape and situations of medical futility or where the health of the mother is at stake. Unlike most others, it defines a fetus as a “natural person” and “human being” once a heartbeat is detected.

That means any fetus with a detectable heartbeat is included in a count of the state’s population and trigger child support obligations and tax benefits. The law also includes penalties for doctors, pharmacists and mothers who violate the restrictions by terminating a pregnancy.

The emergence of HB 481 set off one of the most divisive and emotional legislative fights in Georgia in years. Opponents dressed as characters from the dystopian TV show "The Handmaid's Tale" lined the Capitol hallways; the actress Alyssa Milano delivered a petition to Kemp's office threatening a boycott.

Under heavy security, the measure passed the Republican-controlled Senate by a party-line vote. But it faced a tougher audience in the Georgia House, where it narrowly passed as a handful of GOP lawmakers voted "no" or skipped it altogether. Only one Democrat supported it.

The fallout over the bill will help shape next year's election. Democrats announced a spate of challenges against Republican lawmakers who voted for the measure days after the legislative session ended. And anti-abortion groups promised to counter with a new effort to mobilize conservative voters to defend the seats.