The Strasbourg, France-based court ruled that a pregnant woman fighting cancer should have been allowed to get an abortion in Ireland in 2005 rather than being forced to go to England for the procedure.
The judgment put Ireland under pressure to draft a law extending abortion rights to women whose pregnancies represent a potentially fatal threat to their own health. But Catholic leaders and anti-abortion activists insisted that Ireland had no legal obligation to do anything despite the court ruling.
Cardinal Sean Brady, leader of Ireland's 4 million Catholics, said the ruling "leaves future policy in Ireland on protecting the lives of unborn children in the hands of the Irish people and does not oblige Ireland to introduce legislation authorizing abortion."
Ireland has failed to pass any laws supporting a 1992 judgment from the Irish Supreme Court that said Ireland should provide abortions in cases where a woman's life is endangered; including, controversially, by her own threats to commit suicide.
The 18-year delay has created a legal limbo, forcing many women to travel overseas for an abortion rather than rely on Irish doctors fearful of being prosecuted.
In an 11-6 verdict, the 17 Strasbourg judges said Ireland was wrong to keep the legal situation unclear and said the Irish government had offered no credible explanation for its failure. The Irish judge on the panel, Mary Finlay Geoghegan, sided with that majority view.
The judges wrote that Ireland's failure "has resulted in a striking discordance between the theoretical right to a lawful abortion in Ireland on grounds of a relevant risk to a woman's life, and the reality of its practical implementation."
Under Irish law dating back to 1861, a doctor and patient both could be prosecuted for murder if an abortion was later deemed not to be medically necessary.
The Strasbourg court broadly upheld Ireland's right to outlaw abortion in the overwhelming majority of cases because that reflects "the profound moral values of the Irish people in respect of the right to life of the unborn." Voters in this predominantly Catholic nation enshrined that ban into the Irish Constitution in 1983.
But the court found Ireland guilty of violating one woman's rights.
The lawsuit dates back to 2005, when the Irish Family Planning Association sued Ireland's government on behalf of three women who traveled overseas that year for abortions: an Irish woman who had four previous children placed in state care, an Irish woman who didn't want to become a single mother, and a Lithuanian woman living in Ireland who was in remission from a rare form of cancer.
The judges said the first two women had failed to demonstrate that their pregnancies represented a sufficient risk to their health, but the Lithuanian woman faced a life-threatening situation. It ordered Ireland to pay her euro15,000 ($20,000) in damages.
The judges lambasted Ireland's defense claiming that the woman should have petitioned the Irish High Court for the right to have an abortion in Ireland. They said Irish doctors must be given clear legal guidance on the eligibility rules for abortions.
Health Minister Mary Harney said she was confident that Ireland would draft legislation to bring the country's laws into line with its own Supreme Court; but said the step would have to wait for the next government. Ireland faces an unscheduled national election in the spring.
"Clearly we have to legislate, there's no doubt about that," Harney said. "But I don't think we have the capacity to bring forward proposals in a matter of weeks."
Harney noted that the government twice tried to resolve the issue with referendums in 1992 and 2001, but voters on both sides of the abortion argument rejected that constitutional amendment. In both cases, the government sought to limit the right to legal abortion only to cases where the woman was at risk of death; but excluding suicide threats.
She said lawmakers would face a "highly sensitive and complex" debate over what specific definitions should apply for life-threatening conditions. She said pregnant women suffering from cervical cancer, exceptionally high blood pressure or ectopic pregnancies already were receiving abortions in Irish hospitals.
The vast majority of nations in the 47-member Council of Europe permit broad access to abortion, most recently Spain, which legalized first-trimester abortions in July. Only Malta and Vatican City ban the practice outright, while several others seek to limit it to exceptional cases including rape and fetal abnormalities.
European Court of Human Rights judgments are legally binding but difficult to enforce. Council of Europe nations often take years to enact the legal reforms ordered. An offending nation that refuses to observe a court order could be expelled from the Council of Europe, but this has never happened.
Thursday's judgment was the first by the Strasbourg court against Ireland since 1988, when Dublin gay activist David Norris successfully sued the Irish government over its law defining homosexuality as a crime. Ireland legalized homosexuality in 1993.
The Irish Family Planning Association and an Irish lobbying group, Doctors for Choice, welcomed Thursday's verdict.
"Doctors can feel vindicated today. For the first time we can feel confident about discussing abortion as an option for women in medical need without fearing prosecution," said Dr. Mary Favier, director of Doctors for Choice.
But William Binchy, a Trinity College Dublin law professor who advises Ireland's Pro Life Campaign, said the judgment did not explicitly order Ireland to pass any new legislation. He said Ireland should kick the issue back to the public for a fourth referendum.
"What's at stake in this debate is the value of life. The sad experience is that once laws permitting abortion are introduced, they diminish the society's respect for the inherent value of every human life, born or unborn," Binchy said.
And Brady, the Catholic cardinal, suggested that Irish people would never vote to permit abortion even for exceptional cases.
"The direct destruction of an innocent human life can never be justified, however difficult the circumstances," he said. "We are always obliged to act with respect for the inherent right to life of both the mother and the unborn child in the mother's womb. No law which subordinates the rights of any human being to those of other human beings can be regarded as a just law."