There are days when I despair of members of our elected legislature and today is one of them.

The reason for this sinking feeling lies in a seemingly innocuous passage of a commentary by Giles Fraser on the Church of England’s failure to secure enough votes in the General Synod to permit them to ordain female bishops:

And on another front, Diana Johnson, the MP for Hull North, is planning to bring in a 10-minute rule bill in the new year with a simple clause calling for female bishops. There is little doubt that the majority of the House of Commons, like the majority of churchgoers, strongly supports the prospect of women bishops.

Now, I don’t expect MPs to know the ins and outs of every single piece of legislation on the statute books – there’s just too much law for that to be a possibility – but there are some pieces of legislation that I would expect MPs to be pretty well versed in, particularly those precious few statutes which make up the written portion of our largely unwritten constitutional settlement, statutes which certainly include the Bill of Rights 1680 and Magna Carta, the extant version of which dates to 1297 and the reign of Edward I.

In truth, and although Magna Carta has not yet died in vain, there is not much left that is still in force – barely three clauses in fact, the first of which has a particular bearing on the suggestion that a 10-minute rule bill with a simple clause might somehow speed up the process of ratifying the ordination of female Bishops in the Church of England. That clause reads as follows:

1 Confirmation of Liberties.

FIRST, We have granted to God, and by this our present Charter have confirmed, for Us and our Heirs for ever, that the Church of England shall be free, and shall have all her whole Rights and Liberties inviolable. We have granted also, and given to all the Freemen of our Realm, for Us and our Heirs for ever, these Liberties under-written, to have and to hold to them and their Heirs, of Us and our Heirs for ever.

Parliament can certainly call for the Church of England to gets its skates on and sort out this whole women bishop’s business, although why one would do that with a 10-minute rule bill when an Early Day Motion or a backbenchers debate with a simple, non-binding division, would suffice is anyone’s guess. But Parliament certain cannot compel the Church of England to ordain women bishops, not without provoking a constitutional crisis.

Although its perfectly true that all but three clause of Magna Carta have either been repealed outright or superseded by later legislation and, of course, the doctrine of Parliamentary sovereignty asserts that no parliament may pass legislation that binds its successors.

It is nevertheless the case that, so far as I can recall, none of the clauses in Magna Carta that have been repealed included an explicit grant of rights and liberties in perpetuity and it is, therefore, entirely unclear as to whether Parliament could indeed repeal this particular clause, which it would have to do in order to compel the Church of England to ordain women bishops. And even if Parliament pass legislation to repeal this clause it is unclear as to whether the Queen, as the reigning monarch, could give Royal Assent to such a bill. Magna Carta is not, strictly speaking, a piece of Parliamentary legislation, it’s much more a royal proclamation and so, even if Parliament considers that it cannot be bound by this clause it doesn’t automatically follow that the Queen is not bound to honour the grant of right of rights and liberties conferred on the Church by, originally, King John and then, at later dates, by Henry III and Edward I even though the charter itself is impermanent and has been reconfirmed on at least 32 separate occasions, the most recent of which was in 1423 by Henry VI.

It would appear, therefore, that the Queen could dispense with the entire charter and all three remaining clauses, stripping not only the Church of England but also the City of London its historical rights and liberties and undermining the constitutional foundations of the criminal justice system in the process but not necessarily sign off on a bill will disposes of that first clause and the rights and liberties of the Church of England.

All a bit of mess, then, and something that one would some of Diana Johnson more constitutionally-minded parliamentary colleagues will be pointing out her in due course, long before she make a fool of herself and Parliament.