Iowa's "fetal heartbeat" law — the most restrictive abortion limit in the country — violates Iowa Constitution and may not be enforced, a state judge ruled Tuesday.

In his decision striking down the abortion law, Polk County District Judge Michael Huppert cited the Iowa Supreme Court's ruling last year in a challenge to a different abortion-restriction law. The high court held that "a woman's right to decide whether to terminate a pregnancy is a fundamental right under the Iowa Constitution" in that ruling.

The "fetal heartbeat" law, passed last spring, had been on hold during a legal challenge by Planned Parenthood of the Heartland and the American Civil Liberties Union of Iowa. Huppert overturned it in a nine-page ruling Tuesday.

The district court decision is a major victory for backers of legal access to abortion. But anti-abortion advocates have vowed to continue fighting over the issue, at least through Iowa's appellate courts.

Huppert wrote in his decision that defenders of the 2018 "fetal heartbeat" law didn't identify a compelling state interest in barring most abortions after a fetus' heartbeat can be detected.

Gov. Kim Reynolds, a Republican who opposes abortion, signed the law. “I am incredibly disappointed in today’s court ruling, because I believe that if death is determined when a heart stops beating, then a beating heart indicates life," she said in a statement her office released Tuesday.

State Sen. Janet Petersen of Des Moines, the Democrats' leader in the Iowa Senate, praised the ruling. “The extreme law should have been overturned, because it restricted the freedom of Iowa women and girls to care for their bodies, and it forced motherhood on them," she said. "The governor and legislative Republicans should stop attacking women’s health care."

ACLU of Iowa Legal Director Rita Bettis Austen hailed the ruling. “Today’s victory is essential to the rights and safety of women in Iowa,” she wrote in a statement. “It follows in the footsteps of the Iowa Supreme Court decision on abortion in 2018 that recognized the fundamental right to a safe and legal abortion for Iowa women, which cannot be legislated away.”

Maggie DeWitte, executive director of Iowans for Life, said she had been "hopeful this judge would be fair in allowing the matter to go before a fair trial. I think it's a travesty of justice that's not going to happen."

She said she hopes abortion opponents succeed in having Tuesday's ruling overturned on appeal.

Like the previous case, which successfully challenged a 72-hour waiting period for abortions, the "fetal heartbeat' law challenge was brought in state court, and the decision was based on the Iowa Constitution.

Proponents of both abortion-restriction laws had hoped they would lead to challenges before the U.S. Supreme Court of its 1973 "Roe v. Wade" decision. That decision legalizing abortion nationwide was handed down exactly 46 years ago on Tuesday. The weekend prior to the ruling saw the 46th annual March for Life, where thousands of activists gathered in Washington, D.C., to voice anti-abortion sentiments.

But legal scholars have said a decision based on the Iowa Constitution would be difficult to appeal to the U.S. Supreme Court, which has little jurisdiction over state constitutional issues.

Huppert's ruling said there were no facts in dispute, which permitted him to decide the law's fate immediately.

The state was represented by private lawyers from the Thomas More Society, a national group that opposes abortion. Attorney General Tom Miller had declined to have his office defend the law.

The Thomas More lawyers argued in December that the law would not be a blanket ban, as it was described by critics.

The law would ban nearly all abortions after a fetal heartbeat is detected. Critics of the law said that can occur about six weeks into a pregnancy and often before a woman realizes she’s pregnant.

The two abortion providers sued in May, shortly after the law was signed by Reynolds. The lawsuit contends the law violates Iowa women’s due-process rights, their rights to liberty, safety and happiness and their rights to equal protection under Iowa’s constitution.

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