PITTSBURGH – Is your boss a liberal or conservative? If you're a woman, you may want to find out.

New research by two Penn State professors found that how much you get paid could depend on your boss' political views.

Professors Forrest Briscoe and Aparna Joshi of Penn State's Smeal College of Business analyzed performance-based bonuses received by male and female attorneys over a six-year period at one of the nation's largest law firms.

Using campaign contributions as a guide, they found that for associates working for liberal partners in the firm, there was no gender gap in pay. But for those working under conservative partners, the males got bigger bonuses. The partners who supervised the associates were responsible for determining the size of bonuses.

The researchers controlled for variables — including billable hours, associates' backgrounds and other factors. Whether a supervisor was male or female was not statistically significant.

The average difference in bonuses was $5,000 but grew to $15,000 for more senior associates.

"That was pretty striking," said Briscoe, associate professor of management and organization.

The professors said their study is relevant across a wide range of professional and managerial jobs.

Briscoe said it was impossible to say for sure what accounted for the gender differences in pay and emphasized that the study was not suggesting that conservative values were misogynistic.

"We can't say from this study that one group or the other, conservatives or liberals, is necessarily getting it wrong," he said.

Briscoe said liberals may be more "resistant" to the well-documented unconscious male manager bias in the workplace.

Conservatives, on the other hand, "may be more willing to overlook that differences are aligned with gender in allocating bonuses," he said.

"The conservative may focus on the more immediate indicators of differential commitment or performance — e.g. working at the office over the weekend — without considering whether or not they inherently favor men," the professors wrote.

Briscoe said his study suggests that "the values managers have, even though we don't talk about it in the workplace, actually matter a lot."

Companies may want to use the findings to move toward more transparent pay practices, he said.

"If there is a pattern of [managers] who are always associated with big gender pay gaps, maybe that is something that should be looked at."