On his first trip to Africa, Pope Benedict XVI was asked a question about the Catholic Church’s position on the way to fight AIDS. This is how he answered:

Delivered to a continent where 22 million people live with HIV, and which accounted for 75% of all AIDS deaths in 2007, his words provoked strong reactions. Journalists, politicians and AIDS activists from around the world lined up to criticise the Pope’s views: “The Pope deserves no credence” said the New York Times in an editorial; “Impeach the Pope” urged a guest writer in the Washington Post. The British medical journal the Lancet accused him of having “publicly distorted scientific evidence to promote Catholic doctrine”, Former French Prime Minister Alain Juppe suggested that he was “living in a situation of total autism”, while Rebecca Hodes of the Treatment Action Campaign in South Africa described his remarks as “alienating”, “ignorant” and “pernicious”.

The row goes beyond previous disagreements because the Pope appeared to stray from morals, on which he has some claim to authority, into science, on which he does not. His comment was a “testable proposition”, noted The Times in its leader, with “immense implications for human health and welfare.” The article concluded by arguing that “the Vatican must amend its position on Aids.” The specific scientific claim aside, the problem is that it is apparently impossible for the Vatican to do this.

It’s not easy saving souls

Anthony McCarthy, Research Fellow at the Linacre Centre for Healthcare Ethics in London and spokesman for the Catholic Church in England and Wales, explains the reason for the Church’s prohibition of condoms: the moral principle in question is the condemnation of ejaculatory sexual activity outside of the context of the marital act, as expressed in Pope Paul VI’s 1968 encyclical Humanae Vitae (paragraph 12) and the earlier 1930 encyclical promulgated by Pope Pius XI, Casti Connubii (paragraph 23). The marital act, he says, is one in which the couple is “truly united in a joint striving of their bodies towards generation.” The argument against the use of condoms, then, even to prevent AIDS, is that “you’ve actually put a barrier between your ability to completely give yourselves to each other in the only way that can unite you maritally, because the only way to unite you maritally is a generative kind of act.”

But in the case of people with multiple partners, or couples where only one partner has HIV, surely it is better for the Church to counsel the use of condoms? “I think not, because the Church can never recommend that people sin. For example, if someone is going to torture someone else, you could say, 'Make sure your instruments are as clean as possible', and so on. But if you do that, you are intending that they act the way you're telling them to act, and you are actually condoning a sin, and the Church could never do that. Sin is a complete rejection of God, so although there might be awful consequences it's the sin that matters.

“In the case of a married couple where one is infected with HIV”, he adds, “when the risk of transmission is high, in usual circumstances it would appear to be seriously morally wrong to engage in sexual intercourse.”

If you can’t say something nice…

Mr McCarthy’s most telling comments come when I ask him whether, given the scientific evidence that condoms help prevent the spread of AIDS, it would be best for the Pope simply to keep quiet.

The Pope’s concern is to save souls, both within and outside the Church. And in order to do that he has to tell people what kind of behaviour is fulfilling God's will and what kind of behaviour goes directly contrary to that will. Condoms are a proposed technical solution to what has always been fundamentally a moral problem. The Church has to say, “We actually think human beings are better than that, we don't believe that people just get trapped into sex and they have to keep following their desires and it's always going to be the way it is.” The Church and Christ have always said that it doesn't have to be this way, that if you really love someone, you don't give up on them like that. So the Pope has to preach a moral message, and that moral message includes the very solution to the problem. Even if condoms were to work, and of course I don't think they do, but even if that were the case, he would have to speak out.

It doesn’t help that the Church puts up far from a unified front on the issue. Some Cardinals, for example, have suggested that the use of condoms could be “a lesser evil”. Mr McCarthy says that “they are out of line with what the Church is saying, and I think they're mistaken. If you're talking about reducing the amount of bad consequences or evils in a particular situation, then I think yes that makes sense. But if you’re talking about someone committing one sin (using a condom) or committing another sin (infecting someone with AIDS), clearly these are things where the Church can't recommend either.”

More troubling for the Vatican is the existence of organisations like the US-based Catholics for Choice. Seen as representing the full spectrum of Catholic opinion, they are widely quoted in the press. The Times, for example, quoted its president, Jon O’Brien, in a recent piece: “Where there is doubt there is freedom and Catholics can now make up their own minds as to whether they can use [condoms] or not.” In fact, the organisation is, according to the United States Conference of Catholic Bishops, “an arm of the abortion lobby in the United States” and “merits no recognition or support as a Catholic organization.”

It seems impossible, then, that the Vatican could ever change its stance on condoms, even for AIDS prevention. It is certainly true that its position is not dictated by scientific claims about the efficacy of condoms. Even so, prominent Catholics continue to insist that the science is on their side.

A truth more important than the facts

In response to the Pope’s comments, Dr Kevin De Cock, Director of the HIV/AIDS Department at the WHO, said:

This is denied by the Catholic representatives I speak to. Richard Doerflinger, Adjunct Fellow in Bioethics and Public Policy at the National Catholic Bioethics Center in Boston, responded to Dr De Cock’s words directly:

That's not what most Africans are finding! There are people who have blind faith everywhere and not all of them are religious... But the data are there, that [condom distribution] is often a failure and sometimes counterproductive.

Fr Thomas Weinandy is the Executive Director of the Secretariat for Doctrine and Pastoral Practices of the United States Conference of Catholic Bishops. I put to him the recent comments of Prof Quentin Sattentau, Professor of Immunology at the University of Oxford, that “there is a large body of published evidence demonstrating that condom use reduces the risk of acquiring HIV infection, but does not lead to increased sexual activity.” He replies:

The professor at Oxford is refusing to agree with the studies that he doesn't like. Scientists are not the objective nice guys you think they are all the time.

Mr Doerflinger explains the science behind their claims: “There's plenty of data. Condom distribution as a solution to generalised AIDS epidemics is often very disappointing in its results, and there's some data that it makes things worse. [There’s] the whole concept of risk compensation, that people engage in more risky behaviour because they have a false sense of security from the condoms. So I thought his comments were perfectly sensible to anyone who knows the literature.”

Green and not heard

This literature to which he refers does exist, though it is not mainstream. Its principal proponent has been Dr Edward Green, Director of the AIDS Prevention Research Project at Harvard. “The best evidence we have”, he says, “supports the Pope’s comments. There is a consistent association shown by our best studies between greater availability and use of condoms and higher (not lower) HIV infection rates.” He told me:

In epidemics that are population wide, where most HIV is found in the general population, for whatever reason we can't get people to use condoms consistently, and when they use them at all, that seems to have the effect of disinhibiting people's behaviours so they end up taking greater sexual risks and cancelling whatever risk reduction they have gotten from the technology they're using.

Importantly, however, he is not against the promotion of condoms: “I'm not against making them accessible, I'm not against promoting them, it's just that as responsible public health planners, we should admit to ourselves that 50 years into promoting condoms - and the last 25 years have been mostly promoting them for AIDS prevention - they haven't worked in the generalised epidemics of Africa. We should be putting our resources into things that do work.”

This position, that “the best evidence we have supports the Pope’s comments” [that condoms “increase” the problem], and yet “I’m not against promoting them”, seems contradictory. He still hadn’t made up his mind when he was interviewed by the BBC. To clarify, I asked him whether Prof Sattentau was wrong when he said that the Pope’s comments were “entirely counter-productive, and… likely to lead to increases in HIV infection in Africa and elsewhere.”

I guess I'd have to say he's wrong. He means well, and I used to make statements like that myself. He probably is just not aware of the more recent evidence coming out of Africa.

Dr Green emailed me a list of 15 studies in support of his claims. Mr Doerflinger emailed me two documents: some testimony delivered in 2007 to the House Committee on Foreign Affairs by Dr Norman Hearst, in which he claims that “no generalized HIV epidemic has ever been rolled back by a prevention strategy based primarily on condoms”, and a 2006 comment piece published in the Lancet, a British medical journal, warning against the problems of risk compensation in the use of condoms.

If one reads all of these, and follows through all the references, it becomes apparent that despite the high number of ‘analysis’ and ‘opinion’ papers drawing on other studies, there are very few actual trials cited. Of those, these two are representative: “HIV incidence and sexually transmitted disease prevalence associated with condom use: a population study in Rakai, Uganda”, published in the journal AIDS in 2001, and “Increasing Condom Use Without Reducing HIV Risk: Results of a Controlled Community Trial in Uganda”, published in the same in 2005.

From data to theory

The first notes that “inconsistent condom use may actually be an ‘enabling’ process allowing individuals to persist in high-risk behaviors with a false sense of security”, and concludes:

It is critical that programs discourage irregular use of condoms and emphasize consistency of use… In populations where HIV prevalence is very high, it is imperative that program and policy adopt such a free distribution program and promotion of consistent condom use without delay. (My emphasis)

The second, co-authored by Dr Hearst, after warning of its “many limitations”, concludes that:

In aggregate, our data do not support a net reduction in HIV risk through a program focused on condom promotion in this setting. The increase in condom uptake that the intervention produced seems not to have been sufficient to counteract the increase in numbers of sex partners… Future HIV prevention research needs to develop and evaluate interventions that are able to achieve partner reduction and increased condom use. (My emphasis)

It is true, then, that some studies claim that risk compensation “may” be a factor. I put this to Prof Sattentau:

Well there are studies that have looked at that, and there are one or two that suggest that you may increase risk and others that strongly suggest you don't. I disagree, I think, that “the best studies” show that you increase risk. In my opinion the best studies show that you don't.

Importantly, even the studies that do suggest evidence of risk compensation go on to advise that condoms be promoted more effectively - not abandoned. Indeed, scientists are always careful to use the words “consistently and correctly” when talking about condom use. For example, Prof Harold Jaffe, Head of the Department of Public Health at the University of Oxford, told me:

Studies that have looked at HIV risk among people who consistently and correctly used condoms show that risk is decreased. (My emphasis)

Similarly for Dr De Cock:

There is no scientific evidence that promoting the correct and consistent use of condoms has led to alterations in sexual behaviour or increased risk taking. (My emphasis)

Different responses

The two chains of reasoning are now more clear. The scientists argue: “condoms work when used correctly and consistently, so we should make sure that people use them that way.” Catholics such as Fr Weinandy argue: “condoms don’t work when not used correctly and consistently, therefore they shouldn’t be promoted at all.”

The crucial question, then, is how easy is it to ensure that people use condoms in the right way? An article published in the journal Science in May 2008, “Reassessing HIV Prevention”, again co-authored by Dr Hearst, notes:

Although condom use has also likely contributed to HIV decline in some generalized epidemics, there is no evidence of a primary role. This is because consistent condom use has not reached a sufficiently high level, even after many years of widespread and often aggressive promotion, to produce a measurable slowing of new infections in the generalized epidemics of Sub-Saharan Africa. When most transmission occurs within more regular and, typically, concurrent partnerships, consistent condom use is exceedingly difficult to maintain.

The UN published an official response to the article, disputing its claims. When I speak to Elizabeth Mataka, the current UN Special Envoy for HIV/AIDS in Africa, she explains:

I think condoms remain a very useful tool within a package of other options. It's not the only option but I don't discount the use of condoms. I don't think people go around saying there are condoms and therefore I can have as much sex as I like. I think rather, people need condoms to be more accessible, more affordable and also maybe women empowered to negotiate their usage.

Stephen Lewis, Professor in Global Health at McMaster University, is more blunt:

In his opinion, UNAIDS, the Joint United Nations Programme on HIV/AIDS, has been tragically slow to recognise the efficacy of new prevention vehicles such as male circumcision, treatment as prevention and the discouragement of concurrent partnerships. “There was a failure of leadership in those areas which would have made the debate around the condom utterly irrelevant because we would have found other vehicles and avenues for prevention which would make a difference,” he says.

He is also not sure that the Pope has much influence in Africa in the first place: “I have a foundation that supports many Catholic projects on the ground, and it's pretty obvious that nobody pays attention to the papal edicts.”

But to those who suggest a causal link between condom distribution and higher HIV prevalence, he says: “I think you can argue that even if you have the use of condoms, and support for condoms hasn't resulted in lower prevalence rates in many areas, without the use of condoms those prevalence rates would be even more astronomic than they are now.”

It is clear that the argument is going to continue. It is also clear that although, as Prof Sattentau points out, “there's almost always some evidence that will go one way and some evidence that will go the other way”, the most important scientists continue to believe that “condoms have played a decisive role in HIV prevention efforts in many countries”, and that condom use remains “a critical element in a comprehensive, effective and sustainable approach to HIV prevention and treatment.”

The real morals of the story

This upset has been ugly, and there will be no progress until some important lessons are learned.

First, the Pope should not make claims that can be interpreted as being scientific. Whichever way he meant it, the statement that condoms “increase” the problem of AIDS was seen by the world as a assertion of fact: namely, that the distribution of condoms causes the disease to spread. The scientific consensus is that this is not true, and it is irresponsible to assert to the contrary. Other Catholics should stop attempting to distort the evidence in their favour, and admit that their position is not dictated by scientific claims in the first place.

Second, Catholics themselves need to be educated on what the Church actually teaches. The Vatican’s opposition to condoms, even for the purpose of AIDS prevention, is unequivocal, and is not going to change. Members of the Church hierarchy and others should stop pretending otherwise. Someone who writes in the Washington Post that “I am a Catholic and the idea that [the Pope] is God's spokesperson on earth is absurd to me” deserves no credence. Once Catholics gain a fuller understanding of what their faith entails, they can choose to accept or reject it with intellectual honesty: those who seek a “reformed” tradition which allows Christian truth to be re-interpreted certainly have the option.

Third, the Pope should not be criticised for providing moral leadership to Catholics: that is, after all, his job. He has no reason to compromise what his Church sees as God’s truth, and Catholics have the right to act upon it. The Pope’s moral teaching, properly followed, would help to solve the problem of AIDS, not contribute to it. The problem occurs only if people choose to accept the “no condoms” teaching but reject the others. The solution to this is education: Catholics in Africa have the right to the scientific truth as well as the Pope’s version of the moral truth. If everybody were presented with both elements - “you should not engage in sexual activity outside of the marital act (and so should never need to use a condom)” and “the condom is the single, most efficient, available technology to reduce the sexual transmission of HIV” - they could be trusted to make the correct decision. In this way, many lives - and perhaps even souls - might be saved.