Sir

The public often question the validity and economic implications of scientific assessments of biological diversity. Various interest groups, in particular, complain because they weren't consulted. The European Commission therefore decided to open up the assessment process to online commenting, and the outcome will shortly be made public in a report. However, we believe that allowing science and politics to mix is likely to compromise biodiversity conservation.

The European Union's birds and habitats directives form a globally unique legislative framework for protecting and monitoring the status of biological diversity across national borders (see http://tinyurl.com/nk689c). In total, 25 countries have produced 8,820 scientific assessments to evaluate the current status and trends in species populations and habitats of key European interest (see http://tinyurl.com/lz3z8a). One aim of these assessments is to provide relevant scientific information to support the implementation of environmental and sustainable development policies. The information gained will help in setting up new biodiversity goals to replace the targets for 2010, which mostly remain unmet.

The European Commission's decision to include Internet-based comments in the assessment process attracted views from various interest groups and non-specialists with a political agenda. The consultation web tool was used by 170 authors in some 4,000 visits, providing several hundred informal comments on the assessments. The report will reveal the bearing that these have had on the scientific process.

Our concern is that interest groups are now able to manipulate important scientific conclusions. Member states may be persuaded to modify assessments for threatened species such as seals or wolves, for example, because these are perceived to have a harmful impact on populations of economically important species (fish and reindeer, respectively).

It might be argued that such assessments should not be left to scientists, when the political decisions resting on them concern the whole of society. However, policy-makers must base their decisions on accurate scientific information. Allowing inconvenient data to be distorted to guide decision-making could mask important early warning signs.

Science and politics must be kept separate. The task of scientists is to provide transparent information. The task of politicians is to evaluate this information in the light of society's interests before making their decisions. Don't let biodiversity conservation be undermined by political tainting of scientific endeavour.