Friends in High Places.

We demonstrate that personal connections amongst U.S. politicians have a significant impact on Senate voting behavior. Networks based on alumni connections between politicians are consistent predictors of voting behavior. We estimate sharp measures that control for common characteristics of the network, as well as heterogeneous impacts of a common network characteristic across votes. We find that the effect of alumni networks is close to 60% as large as the effect of state-level considerations. The network effects we identify are stronger for more tightly linked networks, and at times when votes are most valuable. We show that politicians use school ties as a mechanism to engage in vote trading (“logrolling”), and that alumni networks help facilitate the procurement of discretionary earmarks. * We would like to thank Anup Agrawal, Dan Bergstresser, Ethan Cohen-Cole, Shawn Cole, Josh Coval, Bernard Dumas, David Primo, Ben Esty, Fritz Foley, Ken Froot, Burton Hollifield, Victoria Ivashina, Jim Kau, Harold Mulherin, Lukasz Pomorski, Keith Poole, Roberto Rigobon, Michael Roberts, John Karl Scholz, Bill Schwert, Toby Stuart, Marco van der Leij, Rick Wilson, three anonymous referees, and seminar participants at Arizona State University, Bentley University, UCBerkeley, Carnegie Mellon University, Columbia University, DePaul University, University of Georgia, Harvard Business School, INSEAD, NYU Stern School of Business, University of Michigan, Rice University, University of Southern California, University of Texas at Austin, University of Texas at Dallas, University of Toronto, Wharton, Jane Street Capital, the State Street Global Markets Annual Research Retreat, the Cambridge Conference on Financial Networks, and the American Finance Association for helpful comments. We also thank David Kim for excellent research assistance. We are grateful for funding from the National Science Foundation.