Reforming election policies across the U.S. and modifying the way leaders are selected in Congress could help reduce polarization in American politics, according to a report co-written by Harvard Kennedy School Lecturer Elaine C. Kamarck and Brookings Institution Senior Fellow William A. Galston.

The report, released Wednesday and titled “The Still-Vital Center: Moderates, Democrats, and the Renewal of American Politics,” explores possible causes of polarization in American politics as well as measures that could be implemented to improve the situation in the aftermath of last month’s shooting in Tucson, Ariz.

“The shooting in Arizona got the country talking about the hostility in politics,” Kamarck said. “We are looking at some deeper structural causes for incivility in American politics.”

The study was commissioned by the Washington-based think tank Third Way in an attempt to launch dialogue among scholars about concrete ways to address extremism in American politics, said Anne Kim, the organization’s domestic policy director.

“I think this report is going to be a foundational document for a new movement inside American politics to fight against polarization,” Kim said.

According to Galston and Kamarck, one way to reduce extremism in American politics is to open primaries to all voters instead of restraining them to members of particular political parties.

“It would open up the possibility that moderation and compromise might be rewarded rather than punished,” they wrote.

The authors also suggest that modifying district boundaries would make districts less partisan, and that requiring a super-majority  to elect Congressional leaders would favor cross-party collaboration.

Institute of Politics director C. M. Trey Grayson ’94, who worked on election programs when he was Kentucky Secretary of State, said he thought the authors came up with realistic propositions.

“Out of three, the open primaries is probably the most likely to happen. You’ve seen states gradually open their primary processes,” he said.

The report also examines moderates—who they say are an influential voting group—as part of a distinct political movement with specific preferences and characteristics.

“They are center-left on social issues, middle of the road on economics, and center-right on foreign policy. They are not ‘liberals in disguise,’ nor are they a ‘mushy middle’ of left-right compromise,” the authors write.

Grayson, a long-time advocate of bipartisanship in American politics, said that he agreed that in today’s polarized climate, the center has an increasingly important role.

“I thought their analysis of the importance of moderates was dead-on,” he said.

—Staff writer Ariane Litalien can be reached at alitalien@college.harvard.edu.