"[N]obody could ever figure out our own political leanings by reading our papers." That's how Andrew Gelman sees his research. In contrast, when Gelman visited GMU, "One thing that struck me about the people I met there was that their research was strongly aligned with their political convictions (generally pro-market, anti-government)."
The function of this distinction is usually to praise the first group and belittle the second, but Gelman's too open-minded for that:
I'm not saying this to put ourselves above (or below) the researchers mentioned above--it's just an interesting distinction to me, of different styles of social science research... I think it takes a certain amount of focus and determination to pursue research on the topics that you consider to be the most politically important. I don't seem to really have this focus and so I end up working more on methodology or on topics that are interesting or seem helpful to somebody even if they aren't necessarily the world's most pressing problems.
At least for me, a lot of Gelman's observations ring true. If you read my autobiography, it's clear that views that I've held since high school have had a big effect on the topics I've worked on. But the mechanism is more complex than Gelman suggests. At least in many cases, the main effect of my background philosophy is to make me impious towards the status quo, which allows me to ask questions that make other researchers uncomfortable.
For example, there's nothing intrinsically libertarian about my claim that voters are irrational. Lenin thought the same thing. But if I were a moderate, apolitical social scientist, I would have picked a less sensitive topic.
Why? Social pressure is part of the reason: Why question a popular, sacred belief, and risk becoming a pariah, unless you already reject the idea that it's sacred? But the deeper problem is that people who see themselves as "apolitical" usually accept - by default - popular views of what is sacred, so they feel nervous or even guilty about asking impious questions.