Political leanings may be inseparable from one’s ability to view scientific evidence objectively.

In a study published Sept. 3 in the Social Science Research Network, Yale Law School professor Dan Kahan and his collaborators conducted experiments to test the impact of political passions on people’s ability to view data and facts objectively. The researchers also presented potential subjects with an analytical problem that utilized their abilities to draw conclusions from empirical data. Those who received high scores on this problem were determined to have high numeracy — a higher tendency to analyze quantitative information — and were a focus group of the study.

Titled “Motivated Numeracy and Enlightened Self-Government,” the study’s subjects, who were drawn from a random sample of individuals with varying political beliefs, were given either a table of numbers on various skin creams that reduce rashes or a table presented in the context of a law banning citizens from carrying concealed handguns. Though the data in both tables was exactly the same, the study found that an individual’s political leanings, whether liberal or conservative, reduced one’s ability to solve math problems in a political context accurately.

Even members of high-numeracy populations exhibited the same effect — individuals who are good at math may flunk a problem they could otherwise solve if the problem disputed their political beliefs, the study showed.

“Cultural and political leanings do make a difference,” Ohio State University psychology professor and study co-author Ellen Peters said. Though numeracy helps researchers understand the data in front of them, all factors work together to help individuals see what they hope to see, she added.

In the words of science writer Chris Mooney, “Science confirms: politics wrecks your ability to do math.”

The results of this research went against Kahan’s predicted original “Science Comprehension Thesis” stating that individuals with high numeracy are not subject to such polarization.

With this research study, Kahan and his coordinators hoped to address the question of why public conflict over societal risks persist in spite of compelling and accessible scientific evidence. The study’s findings highlight unconscious biases based on political beliefs.

“We need to present data differently,” Peters said, adding that there needs to be a way for individuals to view data objectively.

Kahan arrived at Yale in 1999.