Northern Ireland's strict abortion law is set to come under scrutiny at the UK's highest court.
The case centres on the current law which makes it an offence for a woman to abort with a fatal foetal abnormality or where the pregnancy arises through rape or incest.
Tuesday's proceedings in London before a panel of seven Supreme Court justices, headed by president Lady Hale (pictured), follow earlier legal rulings in Northern Ireland on the controversial issue.
Unlike other parts of the UK, the 1967 Abortion Act does not extend to Northern Ireland, abortion is illegal except where a woman's life is at risk or there is a permanent or serious danger to her mental or physical health.
Anyone who unlawfully carries out an abortion could be jailed for life.
The Northern Ireland Human Rights Commission (NIHRC), an independent body established following the 1998 Good Friday Agreement, launched judicial review proceedings in 2014.
It argues that the current law's effect on women is incompatible with rights under the European Convention on Human Rights (ECHR).
The High Court in Belfast made a declaration in December 2015 that the criminal law was incompatible with Article 8 of the ECHR, the right to respect for private and family life, because of the absence of exceptions to the general prohibition on abortion in cases of fatal foetal abnormalities and pregnancies resulting from sexual offences.
But that decision was overturned in June this year by three of Northern Ireland's most senior judges.
The appeal judges said the law in Northern Ireland should be left to the Stormont Assembly and not judges, saying that the complex moral and religious questions behind the issue should be determined by a legislature rather than a court.
And they said that the issue should go before the UK's Supreme Court.
The Northern Ireland Assembly voted in February last year against legalising abortion in cases of fatal foetal abnormality and rape or incest.
A fatal foetal abnormality means doctors believe an unborn child has a terminal condition and will die in the womb or shortly after birth.
The Supreme Court will hear a challenge by the NIHRC against the ruling of the appeal judges.
Lady Hale, along with deputy Supreme Court president Lord Mance and the five other justices, are being asked to make findings on two issues.
The first is whether the current legislation is incompatible with Article 8 and other articles which provide protection from torture and inhuman or degrading treatment or punishment and from discrimination, including on the ground of sex.
The second is whether the Northern Ireland Act 1998 entitles the NIHRC to bring the proceedings under the Human Rights Act 1998 to seek a declaration of incompatibility.
The Stormont Executive's senior legal adviser, Attorney General John Larkin QC, with the Justice Department, argue that the commission does not have legal power to bring the case and says it has failed to identify an unlawful act.
During proceedings in Northern Ireland submissions were also made on behalf of women who had to travel to England for abortions.
The Supreme Court hearing is due to last for three days.
Copyright (c) Press Association Ltd. 2017, All Rights Reserved. Picture (c) PA Wire.