Professor David Nutt was sacked yesterday as head of the Advisory Council on the Misuse of Drugs. The Home Secretary, Alan Johnson, accused Professor Nutt of stepping over the line which separates advice and policymaking in a public lecture this week.

Yet it is worth looking at precisely what Professor Nutt said. The point he made was that the Government's reclassification of cannabis from class C to class B was not justified by research into the danger the drug poses to health. He also called for a more rational official evaluation of the harm inflicted by all narcotic substances. Isn't this the sort of scientifically-based independent thinking Professor Nutt was supposed to produce? Or does this Government only want to hear advice that it is already inclined to follow?

It is hard not to suspect that Professor Nutt's real crime in the eyes of the Government was not his interference in politics but the fact that his words embarrassed ministers.