Judge Carlton W Reeves of the US District Court in Jackson issued a preliminary injunction against the ban, delivering another judicial rebuke of laws that seek to forbid abortions early in pregnancy — a type of measure that has gained traction across the southern states this year.
The decision was also at least the second since November that limited Mississippi’s efforts to restrict abortions.
The law “threatens immediate harm to women’s rights” and “prevents a woman’s free choice, which is central to personal dignity and autonomy,” Mr Reeves wrote in his ruling.
“This injury outweighs any interest the state might have in banning abortions after the detection of a foetal heartbeat.”
The Mississippi law, which was to take effect 1 July, would have barred abortions once health care providers were able to detect the pulsing of what would become a foetus’ heart, which can be as early as six weeks into pregnancy.
The law was just one of the year’s foetal heartbeat bills that, supporters and critics alike said, would effectively ban abortions before many women even knew they were pregnant.
Under the Mississippi law, abortions would have been permitted after the detection of foetal pulsing only to save a woman’s life or “to prevent a serious risk of the substantial and irreversible impairment of a major bodily function of the pregnant woman.”
Doctors who performed abortions that were illegal under the statute could have been jailed for up to six months.
But the history of courtroom defeats has not deterred abortion critics, who have championed similar restrictions this year in, among other states, Georgia and Ohio. Louisiana legislators are expected to vote on a comparable proposal next week.
The decision by Mr Reeves, an appointee of former president Barack Obama, was widely expected.
The judge appeared sceptical of the law during a hearing on Tuesday, and in a decision last year that blocked Mississippi’s 15-week ban, he lashed out at state leaders for pressing proposals that he felt plainly defied Roe v Wade, the 1973 Supreme Court ruling that legalised abortion nationwide.
“The state chose to pass a law it knew was unconstitutional to endorse a decades-long campaign, fuelled by national interest groups, to ask the Supreme Court to overturn Roe v Wade,” the judge wrote in November.
“This court follows the commands of the Supreme Court and the dictates of the United States Constitution, rather than the disingenuous calculations of the Mississippi Legislature.”
He added, in a footnote that drew widespread attention beyond the state, that the Legislature’s “professed interest in ‘women’s health’ is pure gas-lighting.”
The legal challenge to Mississippi’s new law was brought by the state’s only abortion clinic, Jackson Women’s Health Organisation.
The state will almost certainly appeal the decision to the 5th US Circuit Court of Appeals, in New Orleans. In fact, Republican politicians in Jackson have effectively pledged a blank check to try to defend the law.
“We will all answer to the good Lord one day,” governor Phil Bryant wrote on Twitter before he signed the measure into law in March. “I will say in this instance, ‘I fought for the lives of innocent babies, even under threat of legal action.’”
In recent interviews, two of the law’s leading architects in Mississippi said they had pushed the measure through the Legislature this year after they believed that Virginia’s Democratic governor had effectively endorsed infanticide.
In a radio interview over the winter, Ralph Northam, the Democratic governor, described a situation in which an infant would be delivered with severe deformities, and then a “discussion would ensue between the physicians and the mother.”
Mr Northam’s comments alarmed social conservatives across the country.
In Jackson, lieutenant governor Tate Reeves, a candidate for governor, summoned senator Joey Fillingane, one of the Legislature’s leading critics of abortion, to his state Capitol office. There, in a meeting that lasted just a few minutes, they agreed to move the heartbeat legislation that Republican leaders had planned to let stall.
“Tate looked at me and was like, ‘I think this is the year we’ve got to do something a little more bold,’” Mr Fillingane recalled ahead of the hearing before Mr Reeves. “We just felt like this is a bridge too far. We’re not going to sit back and be passive and lackadaisical.”
But the law’s critics said the measure was but another chapter in Mississippi’s protracted quest to restrict abortions. After the governor signed the measure, they quickly went to Mr Reeves’ court to request an injunction.
The ban “continues a long-running strategy by Mississippi lawmakers and national anti-abortion special interest groups to eliminate abortion in the state, and ultimately the entire nation,” lawyers for the Centre for Reproductive Rights said in a court filing in the suit. “The 6 Week Ban is on a collision course with Roe v Wade and its progeny, by design.”
The New York Times