The Convention set up by the Irish Government to bring the country's constitution up-to-date has recommended that the offence of blasphemy should be removed from the constitution in its current form and replaced with a general provision that would include incitement to religious hatred.

But Terry Sanderson, President of the National Secular Society warned that such a move could make things even worse.

"When the blasphemy law in England was scrapped there was a similar call for a replacement. It came as the Racial and Religious Hatred Act. In its original form this was much more restrictive than the blasphemy law – which had become obsolete and unusable anyway. "It was only after vigorous campaigning by the National Secular Society and others that the legislation was amended to protect free speech. The Irish legislators should learn from that and not create a law that gives religious groups an open door to suppress criticism and claim 'religious hatred' whenever someone says something that they don't like. Unless it is carefully framed, such a law has all the potential to be another form of blasphemy law, but one that has teeth."

Mr Sanderson said no-one had been prosecuted under the present blasphemy provisions, but a more catch-all law could open the floodgates to all kinds of accusations of 'religious hatred' that could significantly impinge on free expression.

He said that there were religious groups that were anxious to have legal methods of silencing critics or mockers of their faith. They should not be handed that tool by the Irish Government.

Dr Ali Selim of the Islamic Cultural Centre of Ireland said blasphemy law should be retained, arguing that freedom of expression should not be "unrestrained" and must be used responsibly.

Separately, the Order of the Knights of St Columbanus had argued that the blasphemy law served to safeguard the right of believers "not to suffer unwarranted offence arising from the gratuitous impugning of sacred matter".

At present, the Irish Constitution explicitly states that blasphemy — speaking sacrilegiously about God — should be a crime. Article 40.6.1.i states:

"The publication or utterance of blasphemous, seditious, or indecent matter is an offence which shall be punishable in accordance with law."

Blasphemy became a criminal offence in 2009 under defamation laws introduced by then-Minister Dermot Ahern, who argued that the Constitution requires that blasphemy be regarded as a criminal offence.

But Dr Neville Cox of Trinity College Dublin said the relevant part of the 2009 Defamation Act, which sets a maximum fine of €25,000 for those found guilty of publishing or uttering blasphemous material, was too tightly drawn to be applied in practice.

He said the law's requirement that a publisher must be proven to have intended to cause outrage among a substantial number of a religion's adherents meant it "will be very difficult successfully to prosecute the offence".

Dr Cox also pointed to a decision by the Supreme Court in Corway v Independent Newspapers, a 1999 case in which the court said it couldn't define blasphemy and therefore couldn't apply the constitutional prohibition. "What this did was render the crime of blasphemy a dead letter," he said.

Sinn Féin Senator Kathryn Reilly pointed to a UN report which said that blasphemy laws are not compatible with human rights. "Blasphemy is not a valid offence in public law and should not be a criminal offence in a democratic society that respects diversity," she said.

Separately, the Irish Council of Churches said that the current reference to blasphemy is 'largely obsolete' and could be seen as part of a range of measures used to 'justify violence and oppression against minorities in other parts of the world'.