If politics was an exact science, then the two papers published in this week's issue on the relationship between bovine spongiform encephalopathy (BSE) in cattle and Creutzfeldt-Jakob disease (CJD) in humans might be read as the final chapter — if not the postscript — in an unhappy saga which opened almost exactly ten years ago. Both papers, one based on work carried out by a team headed by Moira Bruce at the Institute of Animal Health in Edinburgh, the other by researchers led by John Collinge at St Mary's Hospital in London, point in the same direction, namely that the agent responsible for the two diseases is identical, and that the human disease was contracted from eating contaminated beef (see pages 498-501, and ). And both will therefore help to dispel whatever few doubts may continue to linger that alternative explanations remain possible.

But if the scientific answer to the question “can BSE cause CJD?” now appears to have been answered, many political questions are still unresolved. How did the government and its advisers react to the initial news of a possible new type of disease spreading through British herds? Was the appropriate balance struck between the need to warn consumers and a concern not to undermine a multibillion pound cattle industry? And were official actions in any way to blame for the 20 new-variant-CJD deaths that have occurred so far — an issue of critical importance to the relatives of those who have died, in their fight to recover the costs of providing medical treatment?

There are deeper issues that reach to the heart of the way in which government-funded science is organized, both in Britain and elsewhere. Is there a genuine risk that government research institutes and advisory committees may be influenced by the mission statements of the departments to which they are responsible in a way that distorts their assessment of sensitive issues? Does the BSE crisis strengthen the argument for more investment in basic long-term research, not linked to a specific strategic objective, at such institutes? Or does it give weight to the alternative argument that such work should be done by disinterested outside groups, for example in universities?

Of course, many important lessons have already been learnt in Whitehall. There is, for example, reported to be a far greater awareness of the need to listen to external scientific experts and to make research data available to their scrutiny — even if this could have embarrassing implications. The government's long-awaited reaction to the proposals for a Food Standards Agency is likely to reflect an awareness of the need to make consumer interests more broadly represented in food policy and food research. Closer attention is being paid to public statements about what ministers consider to be ‘safe’ or ‘dangerous’. And even the new research provides no reason for believing that health measures taken in recent years to curb the spread of BSE have been inadequate.

But it is important that the issue is not left there. There is also a question of how to build public trust in the way in which the government handles scientific issues in a modern, media-based society — an issue of broad interest to any industrial democracy. There is no turning back the clock, and it is important that such a review does not turn into a witch-hunt; many of those who have found themselves in the dock in recent years undoubtedly acted in what they considered to be the best public interest while struggling with incomplete scientific information. But there are still lessons to be learnt, and further changes to be made, to reduce the chances of such a major health hazard recurring. A review that keeps this goal clearly in mind, gathers the appropriate evidence and delivers a clear and impartial judgement on why mistakes were made and what can be done to avoid them, would be a welcome and refreshing step.