Senior MPs and an influential group of Peers have questioned the fast-tracking of the Succession to the Crown Bill, warning about the “unintended consequences” of a change in the law.
Under new proposals, future heirs to the throne will be allowed to marry Roman Catholics.
But many are concerned because any children from such a marriage must be raised Roman Catholic.
A Roman Catholic heir could spark a constitutional crisis which may result in the disestablishment of the Church of England.
During a debate on the Bill in the House of Commons on Tuesday, MPs criticised the speed of the legislation, and said more time was needed to look into the effects of a change in the law.
Tory MP Nicholas Soames warned of the “unwanted, unintended consequences that often flow from tinkering with legislation of this type and could damage the crucial relationship between church and state”.
He suggested removing the Roman Catholic marriage ban might make it more likely that a Roman Catholic would eventually succeed to the throne – sparking a constitutional crisis.
Sir Gerald Howarth MP also warned about the dangers of changing the constitution, saying the implications have not been properly examined.
He said that if a monarch married a Roman Catholic and had a child: “There would therefore arise a potential conflict of interest in the mind of that person as to which was going to command their loyalty—their loyalty to their faith or their loyalty to the Crown.”
The House of Lords Constitution Committee has also raised concerns about the change, saying it may have “unintended consequences” and needs to be explored fully.
Baroness Jay of Paddington, Chairman of the Committee, said: “The Government appear to want to legislate on royal succession as quickly as possible.”
She added: “This risks shortcutting proper parliamentary scrutiny. The Succession to the Crown Bill is clearly of constitutional significance and as such should not be treated as fast-track legislation.”
The committee said its primary concern is the relationship between the monarchy, the Church of England, and the Roman Catholic Church, in light of its “often conflicted history stretching back to the English Reformation in the 16th century”.
Prince Charles has also reportedly raised doubts about the Bill to a permanent secretary at the Cabinet Office.
According to sources, he believes the potential consequences for the delicate relationship between the state and the Church of England have not been thought through.