In a debate at Holy- rood this week, Nationalist and Labour MSPs will call for the Act of Settlement, which prevents Catholics acceding to the throne, to be scrapped.
The move follows Prime Minister David Cameron’s announcement that the act was to be reformed to lift the ban on an heir to the throne marrying a Catholic, along with the removal of the “primogeniture” rule, which gives a male heir precedence over a female in the line of succession.
At the time, First Minister Alex Salmond hailed the historic move but said it was “disappointing that the reform has stopped short of removing the unjustifiable barrier on a Catholic becoming monarch”.
The move is expected to be passed in the Scottish parliament, and although it will have no direct effect on Cameron’s government it wil be seen as an embarrassing pressure.
The Catholic Church said the reforms announced last month were a “dog’s breakfast”. It pointed out that if the heir to the throne did marry a Catholic, their children would be ruled out of succession if brought up as Catholics.
The issue carries further constitutional significance, as any move to allow a Catholic monarch would require amendment to the 1707 Act of Union, which binds Scotland and England.
The First Minister, who has called on Cameron to end the ban, is also understood to have raised the matter with Deputy PM Nick Clegg.
Last night, SNP Edinburgh MSP Jim Eadie said: “The Act of Settlement is a centuries-old anachronism and it is a deep disappointment that, while some discrimination is being removed, the steps have not been put in place to end the bar on a Catholic becoming monarch.”
He added: “I welcome the decision to end discrimination on the grounds of gender or marriage. These steps are long overdue but do not resolve the problem. There should be no discrimination in any of our institutions on the grounds of religion.”
The motion at Holyrood has the backing of 31 MSPs. A Catholic Church spokesman pressed other MSPs to back the move.
He said: “It is to be hoped this will be used as an opportunity for MSPs to endorse an obviously anti-sectarian initiative – given that the Act of Settlement is demonstrably sectarian in nature.”
He added: “The current formula is a dog’s breakfast. What if the monarch marries a Catholic and brings up their children as Catholics?”
Figures last week showed the number of religious hate crimes has risen by 10 per cent over the last year, with most offences targeting Catholics.
The campaign to reform the Act of Settlement dates back years, having been called “Britain’s grubby little secret” by former Scottish Secretary Lord Forysth.
However, any change would raise questions for the Church of England’s status as an established Church. One solution would be to adopt the constitution of the Kirk, where the monarch is represented by a lord high commissioner – reflecting its role as the national Church, and the monarch’s position as a member.
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