THERE is perplexity among Roman Catholics in England and Wales about what their bishops intend by a new document that carries the sub-heading "Why the Church provides Catholic schools". It is a broad-brush defence of church schools which insists that they are not merely for the benefit of the faithful, but are a public good, and enhance the whole of society. Eyebrows have been raised at the sections about the kind of people who are fit to take positions of leadership in those schools.

Or, to be more precise, what kind of people are not fit to be governors, heads, deputy heads, or heads of RE. Among those the document lists as unsuitable are people who have married in a non-Catholic church or register office without canonical dispensation. Those who have married after divorce are also to be banned.

And so, of course, are those "maintaining a partnership of intimacy with another person, outside a form of marriage approved by the RC Church and which would, at least in the public forum, carry the presumption from their public behaviour of this being a non-chaste relationship". This is a long-winded way of saying gays.

The National Secular Society has described these restrictions as a prurient, tyrannical, and unfair law that "drives a coach and horses through equality legislation, and leaves teachers, paid using public money, uniquely vulnerable to religious discrimination". But then the NSS is also blind to the virtues of church schools, with their emphasis on human dignity and the service of the common good by, to quote the document, "integrating gospel values and the teaching of the Catholic Church into every aspect of learning, teaching, and the totality of school life".

Charitably minded loyalists who do not want to be so indelicate as to suggest that gospel values and the ideology of Rome are not inevitably aligned have been suggesting that cock-up is the explanation. The document is just a re-publication of a 2005 apologia for church schools originally issued only in Birmingham archdiocese, but which has now been reprinted nationally without thought about how a restatement of church policy might look in the context of the row over gay marriage.

The problem with that theory is that the most hard-line sections are not from 2005, but are contained in a newly added supplement on "substantive life choices".

More subtle defenders of the document suggest that what is important is what is omitted. By mentioning only those in leadership positions, they argue, it is effectively saying that classroom teachers will not be dismissed simply for being married after divorce, or for being in a civil partnership. And that, in Vatican terms, is actually rather progressive.

A spokeswoman for the RC Church seemed to endorse that when she said: "This isn't about checking up on people. It is informing people called to leadership positions in Catholic schools that these are the expectations." And the document does hint that exceptions may be made by diocesan education authorities out of "a genuine charitable and pastoral concern not to offend or hurt the individuals involved", or "because it is considered that their professional skills and abilities in respect of governance or leadership are needed in the school and override all other considerations".

That may be code for saying that the current crisis in finding RC head-teachers is already so grave that diocesan authorities had best not initiate witch-hunts. But, in view of recent ultra-conservative episcopal appointments, that can by no means be taken for granted. All this could presage a clampdown that would make the Church of England's muddle over sex and sexuality seem positively benign.

Paul Vallely is associate editor of The Independent.