The Supreme Court has now heard arguments in a case that will decide whether a highly controversial Louisiana law regulating abortion providers can come into effect.

It is the first abortion-related case to come before the court since Donald Trump’s two appointees, Neil Gorsuch and Brett Kavanaugh, took up their seats – and it may prove to be a watershed moment in the future of abortion rights across the US.

What is the law in question?

Louisiana’s Unsafe Abortion Protection Act was signed into law in 2014 by governor Bobby Jindal. Among its various provisions, it requires that doctors who provide abortions have admitting privileges at a hospital within 30 miles.

At the signing ceremony, Jindal said: "Women who resort to the traumatic experience of abortion are entitled to have these procedures performed in a safe environment.

“"The Unsafe Abortion Protection Act ensures that surgical abortion facilities are held to the same safety standards of other outpatient surgical facilities in Louisiana, and this initiative will build on our past work to protect life in our state."

Reproductive health organisation Planned Parenthood says the law is part of “a dangerous national trend”, and that “if this law takes effect, it will pose a serious risk to women across Louisiana”.

Protests across US after abortion laws enforced Show all 20 1 /20 Protests across US after abortion laws enforced Protests across US after abortion laws enforced Missouri Thousands of demonstrators march in support of Planned Parenthood and pro-choice as they protest a state decision that would effectively halt abortions by revoking the license of the last center in the state that performs the procedure, during a rally in St. Louis, Missouri, May 30, 2019. (Photo by SAUL LOEB / AFP) (Photo credit should read SAUL LOEB/AFP/Getty Images) SAUL LOEB AFP/Getty Protests across US after abortion laws enforced Alabama MONTGOMERY, AL - MAY 19: Lindsey Shelton participates in a rally against one of the nation's most restrictive bans on abortions on May 19, 2019 in Montgomery, Alabama. Demonstrators gathered to protest HB 314, a bill passed by the Alabama Legislature last week making almost all abortion procedures illegal. (Photo by Julie Bennett/Getty Images) Julie Bennett Getty Protests across US after abortion laws enforced New York Alison Hickerson from New York City poses for a photo as she take part in a rally in front of the Middle Collegiate Church in the East Village of New York May 21, 2019. - Demonstrations were planned across the US on Tuesday in defense of abortion rights, which activists see as increasingly under attack. The "Day of Action" rallies come after the state of Alabama passed the country's most restrictive abortion ban, prohibiting the procedure in all cases, even rape and incest, unless the mother's life is at risk. Alabama is among about 14 states which have adopted laws banning or drastically restricting access to abortion, according to activists. (Photo by TIMOTHY A. CLARY / AFP) (Photo credit should read TIMOTHY A. CLARY/AFP/Getty Images) TIMOTHY A. CLARY AFP/Getty Protests across US after abortion laws enforced Georgia ATLANTA, GA - MAY 21: Melissa Simpson holds up her arm with "My Body My Choice" written on it during a protest against recently passed abortion ban bills at the Georgia State Capitol building, on May 21, 2019 in Atlanta, United States. The bill would ban abortion when a fetal heartbeat is detected. The Alabama abortion law, signed by Gov. Kay Ivey last week, includes no exceptions for cases of rape and incest, outlawing all abortions except when necessary to prevent serious health problems for the woman. Though women are exempt from criminal and civil liability, the new law punishes doctors for performing an abortion, making the procedure a Class A felony punishable by up to 99 years in prison. (Photo by Elijah Nouvelage/Getty Images) Elijah Nouvelage Getty Protests across US after abortion laws enforced Atlanta ATLANTA, GA - MAY 21: Women hold signs during a protest against recently passed abortion ban bills at the Georgia State Capitol building, on May 21, 2019 in Atlanta, Georgia. The Georgia "heartbeat" bill would ban abortion when a fetal heartbeat is detected. The Alabama abortion law, signed by Gov. Kay Ivey last week, includes no exceptions for cases of rape and incest, outlawing all abortions except when necessary to prevent serious health problems for the woman. Though women are exempt from criminal and civil liability, the new law punishes doctors for performing an abortion, making the procedure a Class A felony punishable by up to 99 years in prison (Photo by Elijah Nouvelage/Getty Images) Elijah Nouvelage Getty Protests across US after abortion laws enforced Alabama Pro-Choice protesters march through the streets of Birmingham, Alabama, during the March For Reproductive Freedom on May 19, 2019. - The state of Alabama passed a near-total abortian ban on May 14, 2019, one of the nation's most restrictive bans on abortions in decades. (Photo by Seth HERALD / AFP) (Photo credit should read SETH HERALD/AFP/Getty Images) SETH HERALD AFP/Getty Protests across US after abortion laws enforced Missouri ST LOUIS, MO - MAY 31: Pro-Choice supporters, along with Planned Parenthood staff celebrate and rally outside the Planned Parenthood Reproductive Health Services Center on May 31, 2019 in St Louis, Missouri. A judge has issued an order allowing Missouri's only abortion clinic to continue providing the service and maintaining their license until June 4. (Photo by Michael Thomas/Getty Images) Michael Thomas Getty Protests across US after abortion laws enforced Alabama Pro-Choice protesters march through the streets of Birmingham, Alabama, during the March For Reproductive Freedom on May 19, 2019. - The state of Alabama passed a near-total abortian ban on May 14, 2019, one of the nation's most restrictive bans on abortions in decades. (Photo by Seth HERALD / AFP) (Photo credit should read SETH HERALD/AFP/Getty Images) SETH HERALD AFP/Getty Protests across US after abortion laws enforced Georgia ATLANTA, GA - MAY 21: People hold signs during a protest against recently passed abortion ban bills at the Georgia State Capitol building, on May 21, 2019 in Atlanta, Georgia. The Georgia "heartbeat" bill would ban abortion when a fetal heartbeat is detected. The Alabama abortion law, signed by Gov. Kay Ivey last week, includes no exceptions for cases of rape and incest, outlawing all abortions except when necessary to prevent serious health problems for the woman. Though women are exempt from criminal and civil liability, the new law punishes doctors for performing an abortion, making the procedure a Class A felony punishable by up to 99 years in prison (Photo by Elijah Nouvelage/Getty Images) Elijah Nouvelage Getty Protests across US after abortion laws enforced Georgia ATLANTA, GA - MAY 21: Melissa Simpson snaps her fingers in support of a speaker during a protest against recently passed abortion ban bills at the Georgia State Capitol building, on May 21, 2019 in Atlanta, Georgia. The Georgia "heartbeat" bill would ban abortion when a fetal heartbeat is detected. The Alabama abortion law, signed by Gov. Kay Ivey last week, includes no exceptions for cases of rape and incest, outlawing all abortions except when necessary to prevent serious health problems for the woman. Though women are exempt from criminal and civil liability, the new law punishes doctors for performing an abortion, making the procedure a Class A felony punishable by up to 99 years in prison (Photo by Elijah Nouvelage/Getty Images) Elijah Nouvelage Getty Protests across US after abortion laws enforced Missouri Thousands of demonstrators march in support of Planned Parenthood and pro-choice as they protest a state decision that would effectively halt abortions by revoking the license of the last center in the state that performs the procedure, during a rally in St. Louis, Missouri, May 30, 2019. (Photo by SAUL LOEB / AFP) (Photo credit should read SAUL LOEB/AFP/Getty Images) SAUL LOEB AFP/Getty Protests across US after abortion laws enforced Washington, DC WASHINGTON, DC - MAY 23: People wait for the start of a news conference regarding womenâ€™s health care, on Capitol Hill May 23, 2019 in Washington, DC. The news conference was held to discuss the reintroduction of the "Women's Health Protection Act " and address the state-based attacks on abortion rights. (Photo by Mark Wilson/Getty Images) Mark Wilson Getty Protests across US after abortion laws enforced Louisiana Handsmaid themed protesters stand outside Jackson Square in the French Quarter of New Orleans, Louisiana, on May 25, 2019, to protest the proposed Heartbeat Bill that will ban abortion after 6 weeks in that state, scheduled for a vote on May 28. (Photo by Emily KASK / AFP) (Photo credit should read EMILY KASK/AFP/Getty Images) EMILY KASK AFP/Getty Protests across US after abortion laws enforced Louisiana Handsmaid themed protesters march down Bourbon Street in the French Quarter of New Orleans, Louisiana, on May 25, 2019, to protest the proposed Heartbeat Bill that will ban abortion after 6 weeks in that state scheduled for a vote on May 28. (Photo by Emily KASK / AFP) (Photo credit should read EMILY KASK/AFP/Getty Images) EMILY KASK AFP/Getty Protests across US after abortion laws enforced Missouri Thousands of demonstrators march in support of Planned Parenthood and pro-choice as they protest a state decision that would effectively halt abortions by revoking the license of the last center in the state that performs the procedure, during a rally in St. Louis, Missouri, May 30, 2019. (Photo by SAUL LOEB / AFP) (Photo credit should read SAUL LOEB/AFP/Getty Images) SAUL LOEB AFP/Getty Protests across US after abortion laws enforced Missouri TOPSHOT - Thousands of demonstrators march in support of Planned Parenthood and pro-choice as they protest a state decision that would effectively halt abortions by revoking the license of the last center in the state that performs the procedure, during a rally in St. Louis, Missouri, May 30, 2019. (Photo by SAUL LOEB / AFP) (Photo credit should read SAUL LOEB/AFP/Getty Images) SAUL LOEB AFP/Getty Protests across US after abortion laws enforced Missouri Pro-choice supporters and staff of Planned Parenthood hold a rally outside the Planned Parenthood Reproductive Health Services Center in St. Louis, Missouri, May 31, 2019, the last location in the state performing abortions, after a US Court announced the clinic could continue operating. - A US Court on May 31, 2019 blocked Missouri from closing the clinic. (Photo by SAUL LOEB / AFP) (Photo credit should read SAUL LOEB/AFP/Getty Images) SAUL LOEB AFP/Getty Protests across US after abortion laws enforced Washington, DC Abortion rights activists rally in front of the US Supreme Court in Washington, DC, on May 21, 2019. - Demonstrations were planned across the US on Tuesday in defense of abortion rights, which activists see as increasingly under attack. The "Day of Action" rallies come after the state of Alabama passed the country's most restrictive abortion ban, prohibiting the procedure in all cases, even rape and incest, unless the mother's life is at risk. Alabama is among about 14 states which have adopted laws banning or drastically restricting access to abortion, according to activists. (Photo by Andrew CABALLERO-REYNOLDS / AFP) (Photo credit should read ANDREW CABALLERO-REYNOLDS/AFP/Getty Images) ANDREW CABALLERO-REYNOLDS AFP/Getty Protests across US after abortion laws enforced Georgia ATLANTA, GA - MAY 21: Heather Masson, left, and Victoria Jernigan hold signs promoting a woman's right to choose during a protest against recently passed abortion ban bills at the Georgia State Capitol building, on May 21, 2019 in Atlanta, Georgia. The bill would ban abortion when a fetal heartbeat is detected. The Alabama abortion law, signed by Gov. Kay Ivey last week, includes no exceptions for cases of rape and incest, outlawing all abortions except when necessary to prevent serious health problems for the woman. Though women are exempt from criminal and civil liability, the new law punishes doctors for performing an abortion, making the procedure a Class A felony punishable by up to 99 years in prison (Photo by Elijah Nouvelage/Getty Images) Elijah Nouvelage Getty Protests across US after abortion laws enforced Alabama Cristina Castor (L) and Julian Kersh pose for a portrait in Ingram Park in Birmingham, Alabama, May 19, 2019 during the March for Reproductive Freedom. - "If this goes all the way and flips Roe v Wade at that point it just seems like where is this going to stop," Kersh said. The state of Alabama passed a near-total abortion ban on May 14, 2019 making it the most restrictive law in the United States. (Photo by Seth HERALD / AFP) (Photo credit should read SETH HERALD/AFP/Getty Images) SETH HERALD AFP/Getty

What case is the Supreme court hearing?

The law is being challenged by doctors who provide abortions and an abortion clinic. They argue that the case is similar to another that the court heard in 2016, namely Whole Woman's Health v Hellerstedt. That case revolved around provisions in a law in Texas that also required abortion providers to have similar admitting privileges.

In a 5-3 vote, the court ruled against the law. In his majority opinion, Justice Steven Breyer wrote that “each of the provisions places a substantial obstacle in the path of women seeking a previability abortion, each constitutes an undue burden on abortion access, and each violates the Federal Constitution.”

The Louisiana law, the challengers say, is unconstitutional for the same reasons. The team defending the law, by contrast, argue that the law benefits abortion patients by making abortion safer, even though the court found that the Texas law offered no such benefit.

What are the justices likely to do?

The oral arguments in the court on 4 March seemed to indicate that the usual ideological split among the justices remains clear – but that doesn’t mean the decision is a foregone conclusion.

The outcome is expected to hinge on chief justice John Roberts. While he is a conservative as a matter of course, he also joined the four liberal justices in voting to stay a lower court’s ruling on the Louisiana law, thus allowing its challengers to file their Supreme Court challenge.

Roberts is also known to value the public trust on which the court depends, and which he feels could be endangered if the court pays little heed to its previous decisions.

The lawyer for the challengers, Julie Rikelman, has appealed directly to this concern, arguing to the justices that because the Louisiana law was “expressly modelled on” the Texas law, the Louisiana case is about “respect for the court’s precedent”.

A decision is expected by the end of June.

Could it overturn Roe v Wade ?

This case is not a direct challenge to Roe v Wade – but if the court allows the law to stand, it will be allowing yet another in a long series of measures that have made abortion harder to access.

Roe v Wade has been under heavy pressure from such measures for a number of years. If the law is upheld, it will become a template for other states to pass “admitting privileges” laws that could radically reduce the number of doctors who are permitted to provide abortions at all. And it could also provide precedents for anti-abortion groups and activists to draw on in future cases.

Both pro-choice and pro-life factions have latched onto the case as potentially decisive. A controversy arose on the day of the oral arguments when Democratic Senator Chuck Schumer, speaking at a pro-choice rally outside the court, warned conservative justices that they would be held to account.

"I want to tell you Gorsuch. I want to tell you Kavanaugh. You have released the whirlwind and you will pay the price,” he said. “You won't know what hit you if you go forward with these awful decisions."

What does Trump have to say?

Donald Trump has made his views on abortion clear. Since his 2016 presidential campaign, he has promised to see Roe v Wade overturned, pledging to appoint justices who would “automatically” overturn the ruling were it to come back to the court.