What role should the public's preferences play in policy formation? I'm prompted to ask by David Goodhart:

The [immigration] debate is over. About 75 per cent of the public think immigration is too high and should be reduced. All three main parties agree.

But of course, whilst public opinion might be settled on one side of the question, most (pdf) expert opinion (pdf)lies on the other side. By "experts" I don't just mean pointy-headed "metropolitan" intellectuals such as Jonathan Portes, but also those members of the public with most experience of immigration. UKIP have polled badly in Birmingham and London which have for years received many immigrants. This is consistent with a finding by Mori (pdf), that whilst most people think immigration is a national problem, they don't believe it to be one in their own area. As Robert Peston says:

The threat to living standards and quality of life of immigration is more in the perception than the reality.

In saying this, I don't mean to imply that all opposition to immigration is wrong. The problem is that reasonable disquiet about immigration - a sense of loss of feelings of home - are commingled with ideas that are mistaken (for example on the economics of migration), illiberal and yes occasionally racist.

Hence my question: why should politicians accede to preferences that are misguided or even evil?

There's a long intellectual tradition which says they shouldn't - from Edmund Burke contending that MPs should over-ride the "hasty opinion" of their constituents, through Jon Elster (pdf) and Eric Posner (pdf) (among many others) to Daniel Hausmann arguing that:

people's preferences are in some circumstances good evidence of what will benefit them. {But] when those circumstances do not obtain and preferences are not good evidence of welfare, there is little reason to satisfy preferences.

This is, of course, no mere theory. Human rights exist precisely to protect people from the illiberal preferences of majorities, and politicians have often over-ridden public opinion - for example in opposing the death penality.

The question then is: is immigration policy an area where the public's preferences should be fulfilled or not? The last Labour government thought not, and (haphazardly) prioritized liberty and economic efficiency over the majority will.

The problem here, of course, is that whilst the role that preferences should play in policy-making and in welfare is a tricky philosophical one, politicians are in the business of seeking power rather than higher ideals. The pressures on them are thus to kow-tow to populism. We should remember, though, that from many perspectives there can and should be more to politics than this. In this sense, Goodhart is wrong: the debate certainly isn't over.