One thing that seems to crop up regularly in both bad science journalism and in pseudoscience and non-science is the idea of a scientific debate. We see creationists talking about "teaching both sides" or the idea that there is "a debate over evolution", but there's also more than enough reports in the media with statements like "this study has reignited a debate" to make it a more general pattern. The implication in each case is that there is a genuine split in the scientific community over the relevant issue, and that perhaps one might go to a conference and see a room full of researchers split down the middle with a good number on each side of the divide advocating their position. By extension, if unspoken, this also rather implies that there is a major stack of evidence for each position, if not, surely there would be no split? After all, if all or the vast majority of the data and analyses pointed the same way, there's not much scope for disagreement.

The truth however, is near inevitably that there is only a very small minority making a disproportionate noise about their case. There is no debate over evolution, or the dinosaurian origin of birds, or that HIV leads to AIDS, or that climate is changing, or a great many others. That there are real, accredited scientists who do not think this is the case is not in doubt (sadly). But that this represents a real schism in the scientific community, that large numbers of researchers take these positions and that it occupies a significant amount of scientific research, or that there is good evidence for that position is certainly incorrect. One or two people arguing a point (and often doing so primarily in the media) does not make a debate.

This can be especially insidious in the media in fact – the creationists have an obvious agenda, anti-vaccinationists are often clearly misguided, but the media should be there to present an unbiased and fair report of the state of play. Unfortunately this seems to be often interpreted as "there are two sides, so both get equal time to make their case" (or "this is new so should have its voice heard"). However this is far from a fair representation when the overwhelming amount of evidence supports one position over the other (and even more so when one side is not even represented by experts in the field).

Not too long ago, I saw a US production on feathered dinosaurs that spent a good portion of its middle section on the alleged 'debate' over the origin of birds. Each side was effectively represented by a couple of researchers who got a couple of minutes screen time to talk about the evidence for their position and against the other. I think a non-expert might have ended up siding with the researchers on the consensus side that birds are indeed dinosaurs, but I also think it might have been close.