Are you fit to call yourself an expert?

* 16 March 2007
* NewScientist.com news service
* Harry Collins

As our well-being, and lives, grow ever more dependent on developments in science and technology, making good decisions about the issues involved is crucial. So we should be very careful about who we allow to judge, says Harry Collins

A SCIENTIST mentions in a radio discussion that there might be a gene for terrorism. Next day, headlines scream: "Scientist says terrorism passed from parent to child." Right-wing politicians demand new birth-control laws. Popular support for the policy grows, backed by newspaper stories of neighbours whose children reproduce their parents' bad habits, and by statistical evidence that seems to show that the Anti-Social Behaviour Orders dreamed up by UK Prime Minister Tony Blair's colleagues run in families. For the first time the phrase "ASBO gene" is heard.

You can see why I think the terrorist gene fantasy is not so far-fetched if you replace it with the controversy that linked autism to the combined mumps, measles and rubella vaccine (MMR). My scenario pretty much describes what happened when some politicians and activists insisted that parents should be given the choice of separate vaccines regardless of the overwhelming scientific evidence that there was no link between autism and MMR.

Something not so different is happening in the US over creationism and evolution, with "intelligent design" providing a so-called scientific controversy that is the thin end of the wedge for politicians. And at the turn of the century in South Africa, President Thabo Mbeki justified his government withholding the anti-retroviral drug AZT from pregnant women by citing the "scientific controversy" over its safety and utility, even though this "controversy" was fuelled by a tiny minority mostly ignored by the research community.

To stop this process taking hold, we need to do many things. The first is to distinguish between technological populism and the good notion of involving the public in discussing technological developments. There are two main ways of achieving this but they are not straightforward. The first concerns the reality of the controversy, the second the degree of technological wisdom and evidence-gathering power attributed to the public.

Scientific controversy comes in three flavours: live controversies, such as that over the safety of genetically modified organisms; one-time controversies that are closed, say, the link between cigarettes and ill health; and non-controversies that should never have been allowed to draw breath.

The borderline between a live and a dead controversy is always a matter of debate. The tobacco lobby, for example, is trying to keep the cigarette/health effect controversy open. And one could argue that the climate change controversy is really closed, with only President Bush and his allies trying to keep it open, arguably for political reasons. In such situations, it's hard for experts in the subject to make much headway.

The difference between real controversies and fakes on the other hand, may be more amenable to analysis. At Cardiff University we have been trying to analyse the expertise of the parties involved in the hope of differentiating between the two. If we can pull it off fairly reliably, this would be a useful contribution from the sociology of science to science itself.

Our methodology involves using a "periodic table" of expertise: we classify all the kinds of expertise we can have according the type and level of tacit knowledge involved. Tacit knowledge captures the abilities you get just from mixing with other people. So we all have lots of tacit knowledge about, say, how to speak English without explicit rules. Experts also have additional tacit knowledge about their specialism.

Armed with our periodic table, the first thing we do is ask what kind of expertise the protagonists have and whether it is suited to the task. With the majority of scientific controversies, the reason it does not help is because all parties generally have lots of expertise. Sometimes they are highly qualified scientists, other times ordinary people who have developed the right level of understanding, either through their working lives or through some burning interest.

It's when we get to the fake controversies that the table does its job. Take the relatively easy case of MMR. The parents of children who developed autism soon after being vaccinated were not scientists or statisticians. They had none of the tacit knowledge that goes with knowing how not to make a statistical generalisation from a single event, yet the media gave their observations great value. Further, the suggestion of the existence of a link, though it came from a qualified researcher, was made at a press conference, and no evidence of the kind an expert would be expected to depend on was ever produced.

The case of intelligent design versus evolution is different. Here, while many of the proponents are well-qualified scientists, it is the way they frame their contribution that fails the test. The motivations are religious, the source of the hypothesis is a book whose authority lies outside science, and the consequences of accepting the hypothesis could seriously threaten the future of scientific enquiry into evolution: God created everything, that's it.

So there may well be a controversy over evolution and intelligent design, which is a perfectly legitimate matter for debate in a democracy, but it is not a scientific controversy, and it is not possible to invoke the existence of scientific controversy to justify the anti-evolution position.

The Mbeki case is different again. Here there were scientists, armed with scientific motivations and methods, arguing on both sides. We can show Mbeki does not merit expert status because he based the scientific part of his judgement not on consulting scientists but on reading the internet and other sources, including scientific papers, in isolation. Instead of immersing himself in the scientific debate, he took it upon himself to make his own synthesis of what he read.

Literature taken alone is often misleading in the case of claim and counterclaim, since publications are not all equal in weight. To stand a chance of finding the right balance between the published arguments you need access to the oral tradition of a science - the views that are continually developing in the conferences and workshops. Mbeki did not refer to anyone who was immersed in the live debate, so it was easy for him to say that he had found a "scientific controversy" in the literature: he lacked the specialist tacit knowledge of the medical area to know how seriously this "controversy" should be taken.

Today, transparency is the must-have when it comes to technological debates. Early consultation can resolve some public anxiety, and mostly this is a good thing. But we are still left with dirty possibilities. Inventing scientific consensus disguises political decisions, but so does inventing scientific controversy where none exists. If we are willing parties, scientific controversies can be conjured at the drop of a hat. We must all share the responsibility of separating real scientific controversies from fake ones or we will unwittingly create the conditions for a technological populism we will live to regret.
“Inventing scientific controversy where none exists disguises political decisions”
From issue 2595 of New Scientist magazine, 16 March 2007, page 54-55