Judges as susceptible to gender bias as laypeople -- and sometimes more so

Judges with more expertise in family law tended to engage in more biased decision-making than those with less experience in family court, said University of Illinois psychology professor Andrea Miller, who conducted the research.

"Judges tend to believe that their vast amount of legal training and logical thinking skills make them immune to these mistakes," she said. "This research is showing that judges are not as immune as maybe they think they are."

The study was conducted at the request of a group representing trial court judges. The judges wanted to know whether their own decision-making was affected by biases that could contribute to social disparities in the legal system.

"They were being very forward-thinking and brave, I think," said Miller, who took on the challenge while working as a postdoctoral researcher at the American Bar Foundation and is continuing the work at Illinois.

The overall sample involved 619 sitting trial court judges and 504 laypeople. All of the judges were asked about their legal expertise. Only those with recent experience on specific types of cases -- for example, child custody cases in family court -- were asked to analyze cases in those fields.

The study evaluated 372 judges' decision-making in a child custody case and 514 judges addressing a workplace discrimination case. The judges read about the cases and then made decisions about how to resolve them. For this analysis, the only thing that varied in each case was the race and gender of those involved in the disputes.

"We're giving them identical case facts and we're only changing a couple of variables that should be legally irrelevant -- race and gender," Miller said.

After the judges made their rulings, they filled out surveys that tested their gender and racial attitudes. (The racial analysis will be published at a later date.)

"The gender ideologies test measured how much the judges consciously support traditional gender roles, where women are more or less confined to domestic caregiving roles and men are confined to more public, career-based roles," Miller said.

Judges in the shared-custody case were more likely than laypeople to give a mother more time with a child than a father. The judges gave mothers, on average, about half a day more time with their children than they gave fathers. Laypeople awarded 0.15 of a day more time to mothers. The judges' tendency to discriminate in this manner coincided with their traditional gender ideologies: The more they supported traditional gender roles for men and women, the more parenting time they gave to the mother in the case.

"In the shared-custody case, the judges were influenced more by gender than the lay sample," Miller said. "An extra half day with a child each week amounts to nearly an extra month of time over the course of a year."

In a workplace discrimination case involving family caregiving, the gender of the plaintiff also affected judges more than laypeople.

"Overall, the judges and the laypeople both saw the woman's case as having more merit than the man's," Miller said. "But the more the judges supported traditional gender roles, the more likely they were to rule against a woman plaintiff on the merits. In other words, decisions in the woman's discrimination case were influenced by the judges' personal ideologies about the proper roles for men and women."

Miller said she wasn't surprised that judges can be influenced by the gender of plaintiffs.

"My first takeaway is that judges are human, just like the rest of us," she said. But she was surprised that judges' expertise in family law did not reduce their tendency to be influenced by their personal ideas about gender.

"The legal system is set up to believe that judges are superhuman logical thinkers and fair decision-makers," Miller said. "And this research shows that even people who are extremely motivated to be fair and make correct decisions are not immune to the same mistakes that everyone else experiences."

Miller is sharing her findings with the judges in the study and working with them to find ways to reduce the role of their personal biases in their courtroom decision-making.