Every social scientist I ever met was liberal-left. This uniformity always struck me as very odd. I accidentally came across a new, rigorous academic analysis of this question in the journal Behavioral and Brain Sciences. The authors are worried by recent problems in social psychology research, including fraud and problems with replicating results. The article, by José Duarte and others (none of whom are conservative), is called Political Diversity Will Improve Social Psychological Science and is easily accessed through Google.
In the US population as a whole, the ratio of liberals to conservatives is 33 per cent to 66 per cent, but 58-66 per cent of professors of social science are liberals and only 5-8 per cent are conservatives. In social psychology, 90 per cent of professors are liberals and 8 per cent are conservatives. On the other hand, the liberal to conservative ratio is about 50-50 in engineering, computer science, health sciences, business and technical fields.
Psychology has robustly demonstrated the value of diversity of viewpoints for improving creativity, discovery and problem-solving. The authors conclude that lack of political diversity undermines much social-psychological science by embedding liberal values into the research questions and methods, by steering researchers away from politically unpalatable research topics and results, and encouraging conclusions to be drawn that mischaracterise liberals and conservatives. Of course, homogeneously conservative social sciences would face the same problem as homogeneously left-liberal social sciences.
Increasing political diversity would improve the quality of social-psychological research by reducing biases such as confirmation bias (favouring evidence that confirms one’s preconceptions) and by allowing dissenting minorities to challenge the majority thinking.
Although lack of political diversity does not threaten the validity of social science research in many areas, it does pose problems in areas relating to the political concerns of the left, for example race, gender, environmentalism, power and inequality, and also in areas where conservatives are studied themselves, such as in moral and political psychology.
Embedding liberal values
To illustrate a typical problem that can arise, the authors cite a social psychology study that found people high in social-dominance orientation are more likely to make unethical decisions, and people high in right-wing authoritarianism are more likely to support their leaders' unethical decisions. However, typical examples of decisions defined as unethical in the study included not taking a female colleague's side in a sexual harassment case and a worker placing the wellbeing of his company over unspecified environmental harm attributed to company operations. In both examples insufficient information was presented about the case to make a considered judgment. In other words, the liberal values of feminism and environmentalism were embedded in the ethical assumptions. Embedding ideological values in measures is dangerous to science.
Another example cited concerns about the scope and direction of prejudice. Social scientists have long considered prejudice and intolerance to be the province of the political right. But some researchers noted most studies of prejudice looked at low-status and left-leaning targets. New research designs were devised to include both left-leaning and right-leaning targets, and the results showed that prejudice is potent both on the left and the right: conservatives are prejudiced against stereotypically left-leaning targets (for example, African-Americans) and liberals are prejudiced against stereotypically right-leaning targets (for example, religious Christians).
In December a well-argued letter to The Irish Times by David Walsh took the field of women's studies to task for promoting the ideological notion that gender is a social construct in the face of scientific evidence that biology plays a prominent role.
Why are the academic social sciences so strongly dominated by left-wing liberals? Self-selection explains some of it. Liberal students are more interested in doing PhDs and pursuing academic careers. Over time this would tip the ratio to the liberal side and the "birds of a feather" effect would accelerate this process. The authors do not accept that this explains the whole phenomenon, and point out that discrimination and hostility expressed towards conservatives by left-wing liberal sociologists strongly discourages conservatives from joining the academic social science community.