The dispute between church leaders and gay rights activists over adoption is highly unusual. Both sides agree, or pretend to, on the chief premise and the essential outcome. The premise is that no individual or group should suffer discrimination on the basis of race, sexual orientation or religious belief. The outcome must be whatever is in the best interests of vulnerable children seeking adoptive parents. But the alternative routes to achieving this diverge so drastically that they have split the Cabinet and left Cardinal Cormac Murphy-O’Connor accused of blackmail while seeking to defend what he sees as the rights of the faithful.

Should publicly funded Catholic adoption agencies, fulfilling their long tradition of helping the dispossessed, be allowed to turn away, on the ground of faith, gay and lesbian couples seeking to adopt? The need for an answer arises because regulations on how to implement the Equality Act 2006 are due to come into force in April. At the same time, Tony Blair has shown a particular interest in involving faith-based organisations more closely in the delivery of public services. His personal beliefs, moreover, incline him to listen sympathetically to submissions on policy from senior clergy.

On gay adoption, he has had two such submissions in quick succession: a warning from Cardinal Murphy-O’Connor that Catholic adoption agencies might close if forced to serve gay couples, and a letter from the Archbishops of Canterbury and York, insisting that “the rights of conscience cannot be made subject to legislation, however well-meaning”.

Mr Blair has indicated a willingness to compromise, if not grant the Catholic agencies an outright exemption from the law. In doing so he risks advocating anti-discrimination legislation that specifically allows discrimination. But he is also clearly open to the view that forcing people to act in contravention of strongly held religious belief is itself a form of discrimination.

The desire to stamp out anti-gay prejudice reflects a welcome change in the morality of this society. But this change has been gradually developing over decades. The best way to change the attitudes of those few who remain convinced that the practice of homosexuality is a sin, and whose faith is deeply held, may be through the balm of conversation and debate rather than through further extensions of the law.

Excessive regulation is never desirable, and it seems unlikely that adoption agencies will be the only charities for which this Act may eventually create difficulties. Catholic agencies handle roughly a third of all adoptions of older and troubled children, who are the most difficult to place. Some already allow single gay men to adopt, which is a step forward, but not couples.

The core of the Equality Act cannot be in dispute. It is unthinkable that gays should be discriminated against in the provision of commercial services, for example a hotel room. But this question of adoption raises competing moral claims that are not so easy to resolve. Prejudice should never be allowed to mas- querade as religious faith. But there is a world of difference between preventing a hotel owner from turning people away on the basis of their sexuality, and allowing an adoption agency to choose its clients.