I've been personally affected by at least two of these "scientific consensus anomalies", scientific issues which, in restropect, were defined by personal biases among scientists, and which they (I hope!) feel rather embarassed about today.

The first was the self-evident and almost totally accepted presence of Martian vegetation. Almost all planetary astronomers, even those that never could see Lowell's canals, conceded that as the Martian ice caps melted in summer, a blue-green stain slowly flowed towards the equator. This was, in the 50s and 60s, almost universally accepted as almost certain evidence of vegetation (probably something like lichens). I only recall one writer as even suggesting an alternative explanation (rising moisture levels affecting soil chemistry and appearance) but even he did not take that interpretation as very realistic. Today, not only do we know there is no vegetation, we also know there was no "blue green stain". In fact, even if there had been, it's highly unlikely it would have been documented from Earth due to the difficulties inherent in visual observations of Mars. My guess as to why this happened? Astronomers desperately wanted to believe there was life on Mars, it fit in with the psychology and emotional makeup of scientists. I know it did with mine.

My other example comes from the controversy that existed between supporters of the steady-state and evolutionary (Big Bang) theories of
cosmology. The former, which fit the Perfect Cosmological Principle, was the most appealing to scientists because it postulated no beginnings, no endings, no changes in overall universal properties, no singularities, and no assumptions. The universe always looked the same, from any place, at any time. It only required one initial assumption: that hydrogen was created continuously in the voids between the galaxies at the modest rate of one atom/meter cubed/century -- a process which was not likely to be verifiable experimentally any time soon. All other observed features were explained neatly, especially after Fred Hoyle proved that nucleogenesis was a normal consequence of stellar evolution and it was not necessary to invoke a Cosmic Egg to explain it. This was the Great White Hope for the Big Bang, and I remember how happy I was to hear it! Most scientists, including this proto-scientist, felt very philosophically satisfied by this cosmology, no embarassing singularities or pseudo-religious creation or end-time events to have to explain away. It fit in with our psychology and emotional makeup.

In both of these cases, the data put the kabosh on our expectations: spacecraft imagery from Mars, and the three degree microwave background from the Big Bang. At least, in the latter case (unlike my Martian example), it can be fairly said that without the crucial deciding observation, both sides had equivalent evidence to support them.

At least, in those two cases, the issues were not further muddied by political and economic agendas.