Skip to content

Expert advice

Last Friday, on BBC Radio 4’s Any Questions?, one of the questioners picked up a theme that had appeared many times in the media during the week.  ‘What is the point’, he asked, ‘of asking for advice from an expert independent panel of advisers and then disregarding it?’. 

He was referring to leaked information that the government’s  Advisory Commission on the Misuse of Drugs was going to recommend that cannabis should retain its current status as a class C drug, but that the Prime Minister was nevertheless ‘minded’ to restore its former B classification.  Class B drugs are regarded as more serious than those of class C, carrying a five year maximum prison sentence for possession, as opposed to the current two years. 

Dr Evan Harris MP, responding, agreed with the questioner that there was indeed no point.  The government, he said, was supposed to be committed to ‘evidence-based policy making’, and that ‘minister after minister’ had told the committee they ‘wanted to make sure their policy was based on evidence’.  The evidence showed there was  ‘no basis to put it (cannabis) into class B’.

The implication is that if Mr Brown ignores the advice of the experts he will be abandoning any claim to evidence-based policy making.  But there is a distinction between evidence and advice.  We don’t yet know the details of the evidence in this case, but presumably it concerns such matters as the likelihood of long-term harm from cannabis use, the relative dangers of the different strengths of cannabis, general patterns of availability and use, the effectiveness of different deterrents, and so on.  But no matter how much information of this kind you get, and no matter how expert the experts who provide it, you cannot generate a policy – the subject of the advice – from this kind of material alone.   Such factual information tells you only that if you do this, then this or that will, or will probably, happen;  if you do something else, then something else will.  To reach conclusions about what you should actually do, you need to involve values – ideas about what matters – as well. 

This means that if people have different values, the same evidence about the facts may lead them to quite different policy conclusions.  Suppose the experts agree, for instance, that cannabis use can lead to severe mental illness.  If your values are to protect people from harm, those values may lead you to do all you can to prevent anyone’s getting hold of cannabis, whereas if your values are libertarian you may just give people the information and leave them to make up their own minds.   Mr Brown’s disagreement with the advice of the committee probably comes not from his doubting or simply disregarding the evidence of the experts, but his disagreement with the – probably unspoken – values that underpin the committee’s advice.  The experts are experts in the facts of the matter, but not the values that should be used – and therefore not in the overall advice given.  ‘Expert advice’ about what you should do is relevant only when you and the expert have pretty well the same values – which is why most patients are willing to accept the expert advice of their doctors.

We need expertise about matters of fact when making policy judgments, but we also need to sort out which values to use – and to recognize that this involves enquiry of a quite different kind.  Indeed, we ideally need to have the values clear before we even start looking for the facts, because the values will determine which facts are relevant.  This is where Mr Brown may indeed be open to criticism.  If the values he thinks we should be using mean that he can reach his conclusion about the level of punishment appropriate for cannabis possession without – for instance – looking into the question of whether heavier punishments have a real deterrent effect, then he should regard it as a waste of time to do the research into deterrence.  Until we have sorted out the purpose of punishment, there is limited point to finding out what it achieves.

In all practical matters the values are the fundamental issues, but they persistently hide behind arguments about facts.  Governments make policies about all kinds of things on the basis of what the experts tell them about the evidence – about whether beef is safe, or whether the gestation limit for abortions should be brought down, or (this morning) whether badgers should be culled in an attempt to stem bovine tuberculosis – when all such issues depend critically on the underlying values.  Mr Brown’s critics, instead of accusing him of disregarding the evidence, should be forcing him to clarify the values according to which the evidence they have produced is irrelevant.  It wouldn’t make policy making easy, but it would make the public debate a good deal less confused and misleading. 

Share on