Beyond Roll Calls : Institutional Change and Partisanship in the U.S. House of Representatives

Congressional polarization is one of the most important topics in American politics, yet over-time comparisons are particularly difficult. For example, Theriault (2008) has found considerably different levels of partisanship across vote types, and Roberts and Smith (2003) have shown that the voting record has changed dramatically during the last half of the 20th century due to institutional change. I argue that institutional reforms changed the voting record in two ways that obscure just how much partisanship has increased since the 1950s. First, the reforms led to an open process that substantially reduced overall party voting. Secondly, as leaders attempted to structure process, procedural partisanship increased dramatically. As a result, polarization studies using roll call votes and beginning at the start of the post-reform era overstate the growth in partisanship during the last four decades