Sir

Calling people who object to deliberate mislabelling of samples a “lynch mob”, as your Opinion article (Nature 415, 101; 2002) does, is like asserting that the collapse of the US energy company Enron was lamentable, and that those employees who lost their retirement savings deserve to be ashamed. It is half true (it is lamentable), but the implied criticism is completely misdirected.

Although conservatives in Congress and the media have indeed harvested a bounty of partisan hay from the misbegotten actions of some agency employees, several important issues remain unresolved.

It is not clear whether the field workers had any fraudulent intent or whether they intended the submitted lynx (Lynx canadensis) hairs to be controls in a test of the analytical lab. But it is clear that earlier samples submitted from the same geographical region to a different lab produced what were subsequently believed to be false positives — lynx hairs were reported from areas with no previous or subsequent evidence of lynx.

How the submission of blind positive controls could have provided a check on false positives is far from clear. More important, the laboratory supposedly being tested in the episode described in your article was in no way suspect in the earlier problems.

Any criticism should be levelled at the field workers who undertook a series of undocumented, informal steps that could be misinterpreted as fraud. Clearly, all would have benefited had they written a protocol, received documented approval, and notified the analytical lab that blind controls would be included in submitted samples.