From the perspective of political leaders, scientific advice is never a panacea. At its best, it can offer views and ideas that will inform sensible and resilient public policy. But it can also impart information that is unwelcome to politicians and senior civil servants, and if that disconnect goes public, the advice and the adviser can become more trouble than they're worth. That's one reason why the planned appointment of the first scientific adviser to the European Union (EU), announced in September, has been less than universally welcomed by senior officials in Brussels.

One such disconnect flared up in Britain late last month, and resulted in the summary dismissal by the home secretary, Alan Johnson, of David Nutt, the chair of the UK Advisory Council on the Misuse of Drugs.

The relationship between advisers and government is distinct to each society. In the United States, for example, the party affiliation of most citizens, including scientists, is in the public domain. Some staff advisers, as well as members of advisory panels on contentious topics, are selected, in part, on party political grounds.

In some European nations, including Britain, senior scientists manage to stay above the party-political fray. But this approach carries its own hazards. One is that there is less circulation of advisers when parties move in and out of power. Another is the conceit that these advisers have no political views of their own, and speak only for science.

Yet the delivery of scientific advice on contentious policy matters is inherently political. When Robert May or David King, as chief scientific advisers to then Prime Minister Tony Blair, vocally supported genetically modified crops and nuclear power, they were taking political positions — on which May, King and Blair were all in happy agreement.

When such advisers stay silent on the British government's largest single technical project — replacing the Trident nuclear submarine fleet — that is a political act. And when Nutt, having survived a run-in with a previous home secretary on drugs policy, went on the radio show Today to air his views on drugs policy and announced that he'd be airing them again at a lecture in London, that too was a political act.

Nutt's firing has triggered a vigorous debate on what scientific advice is and what it is for. But some scientists' contributions to this discussion have pointed to hubris on the part of a scientific establishment that has, over 12 years of Labour government, moved steadily closer to the levers of power.

The idea that the influence of scientific and other elites can become malign is not new. It is almost 50 years since US President Dwight D. Eisenhower planned to warn of the perils of a 'military–industrial–scientific complex', before his science adviser, James Killian, persuaded him to remove the word 'scientific' from his delivered farewell address. Some of Eisenhower's concerns were specific to his time and place. But he was also highlighting the fact that specialist advisers can exercise a large and seldom-noted influence on government — an influence that comes at the expense of other groups in society.

In wresting Labour from its old ideological moorings, Blair and his successor Gordon Brown chose to rely heavily on 'experts' from science and, until last year, finance. These experts spoke New Labour's language. They weren't bolshie ecologists or sociologists from the provinces. Rather, they were upstanding (almost always) men of Oxford, Cambridge or Imperial College, who supported free markets, genetically modified crops, nuclear power and the independent nuclear deterrent. All on purely scientific grounds, of course.

For the scientists, this partnership has worked well. Money has poured in to universities, with the science budget doubling since 1997 in real terms to £6 billion (US$10 billion). More than 70 scientific advisory panels, involving hundreds of scientists, have exercised a growing influence on national policy.

This partnership has offered the nation several advantages, including the revival of the universities and a more-informed public discourse on issues such as global warming. But the benefits to Labour have been less clear-cut. The money invested in science has not triggered the industrial modernization so fervently sought by Brown. And the government's marriage to scientific and financial expertise has coincided with its divorce from Labour's traditional base of support. The rise of the 'expertariat' has not caused the sharp fall in voter turnout, the tidal wave of public cynicism regarding politics and the sense of public life in crisis. Nonetheless, the government's heavy reliance on what looks from the outside like a narrow circle of advisers echoes the situation contemplated by Eisenhower.

As Nutt repeated his view that cannabis and some other recreational drugs are less harmful than alcohol or tobacco, Labour was fighting a difficult by-election in Glasgow North East — one of the most drug-ravaged and economically deprived locales in western Europe, where it can barely afford to sound 'soft on drugs'. Johnson's admittedly rash firing reflected his frustration that, in the run-up to a general election, public pronouncements from persons closely associated with the government cannot conflict too brazenly with the government's own position.

A 6 November statement, signed by 28 scientific leaders, reiterated current best advisory practice — including the right of advisers to speak freely in a personal capacity, and of committees to operate without political interference — and sensibly called on the government to reaffirm its policy on this. More emphatic demands, however — such as calls for scientific panels to set policy or to be protected from dismissal by elected officials — are dangerously naive.

The EU, in developing its advisory apparatus to match the expansion of its political authority under the newly ratified Treaty of Lisbon, can learn from this unseemly spat. Like any polity, the EU will benefit from listening to scientists. But the EU is already afflicted with a reputation for remoteness from the people. It cannot afford to leave the impression, as New Labour has done in Britain, that it is relying on an elite for advice. Vital expertise resides in many segments of society — including ones that consider themselves relatively marginalized, such as social workers or even engineers. In a democracy, the advice of scientists alone cannot be relied upon to deliver sound public policy.