Advertising is often blamed as the, or a, cause of public health problems such as misuse of alcohol or obesity. This paper suggests that the conclusions drawn by researchers owe more to their a priori attitudes than to an even-handed review of the evidence from both sides of the argument. The British Medical Association Science Committee’s 2009 call to ban alcohol advertising and promotion in the UK is taken as a case study. It is characterised by sweeping unsupported assertions, selective use of the literature and factual misreporting. Yet there is, or should be, common ground which should be defined and developed scientifically.