Yale research on belief in free will may have implications for criminal sentencing.

A new paper, written by a team of social psychologists and philosophers, examines why people believe in free will — the concept that individuals can make their own decisions. The study establishes that people have a greater belief in free will after thinking about others committing immoral actions compared to committing morally neutral actions. This finding suggest that belief in free will is a fluid concept, said Jamie Luguri, study co-author and a Yale graduate student.

“One of the reasons that people believe in free will is that they have this desire to hold other people morally responsible when they do bad things,” said Cory Clark, a graduate student at University of California Irvine and the study’s senior author.

In the study, participants either read about a corrupt judge or a neutral article about a job search, subsequently reporting how they felt about the existence of human free will overall. Belief in free will was higher after reading the article about corruption than the story about the job search. Researchers also found that subjects from countries with high crimes rates held stronger believed in free will more strongly.

The researchers also conducted a series of field experiments by sending psychology students one of three messages, a control email or one of two emails reporting cheating in the student body. Students who learned of the cheating reported more belief in free will than those in the control group, confirming earlier findings.

The paper’s conclusions are a significant deviation from previous theories of belief in free will, which reported that people believed others had free will because they believed in their own free will, said Azim Shariff, a professor of social psychology at University of Oregon and study co-author.

In contrast, the current study focuses on motivating factors for believing in the existence of free will, Shariff said. Peter Ditto, a study author and professor of psychology and social behavior at the University of California Irvine, said assigning free will to social deviation justifies punishment.

“[There is] pressure of human cognition to invest things with moral responsibility because blaming people allows you to punish people, which is really important for societal cooperation,” Ditto said.

Ditto said the study conclusions can be demonstrated by conventional judicial proceedings. When deciding whether to try an adolescent as an adult, more severe crimes are often thought of as deserving more severe punishments, since they are thought to result from free will.

Joshua Knobe, a professor of cognitive science and philosophy at Yale and study co-author, said the study demonstrates the power of psychology to answer ancient philosophical questions about the nature of free will.

Clark said she is currently working on a study that may demonstrate that people who believe in free will feel less anxious punishing others.

The study appears in the Journal of Personality and Social Psychology in April.