New Data on State Legislative Polarization – What Does it Mean for Election Policy?
[Image courtesy of American Legislatures Project]
My Twitter feed has been, well, all a-Twitter recently about some new data on legislative polarization compiled by Boris Shor of the University of Chicago and Nolan McCarty of Princeton. It provides a much clearer view of the existence of partisan polarization in this country and provides a basis to compare legislatures to one another. From their blog:
America’s state legislatures are polarized-just like Congress-between liberals and conservatives, Democrats and Republicans. That polarization creates gridlock, when it’s difficult to get legislation passed and policy problems addressed.
But just how polarized are they? We haven’t been able to tell in the past, because we haven’t been able to determine just how liberal or conservative state legislators are in all 50 states. One major reason why is that each state in its own way is rather unique. Massachusetts Republicans aren’t the same as Texas Republicans; the same is true for each state’s Democrats. Nor do they vote on the same things. These immutable differences mean that measuring ideology-and levels of polarization-in state legislatures is much more difficult than that for Congress.
[We] wrote an academic paper in 2011 that explained our method for overcoming this problem … With our aggregate data in hand (and updated from our original estimates), we can begin to make precise comparisons between the states and Congress on a number of dimensions, including polarization. The plot [above] summarizes our measures for legislative polarization, averaging across all the years of our data (approximately 1996-2008), and across both legislative chambers …
The horizontal axis measures the amount of polarization, defined as the average ideological distance between the median of the Democratic and Republican parties in the state legislative chambers; larger numbers indicate more division. The dashed line is the level of Congressional polarization, included as a comparison (“US”) …
What becomes immediately obvious is how different the states are from each other-and Congress-in terms of polarization. Some states, like Louisiana and Rhode Island, have quite unpolarized state legislatures. In Louisiana, both parties are fairly conservative, and in Rhode Island, they are both fairly liberal.
[NOTE: If you are interested in playing with the data yourself it’s available here.]
What does the data from Shor and McCarty mean for the discussions of election policy that are commonplace on this blog? Obviously, it matters; how that works in practice, however, requires a far deeper analysis than I can provide here.
I will note this, though: the states that appear most frequently on this blog tend to be states that skew to the right of the national average; e.g. Colorado, Wisconsin, Ohio, Minnesota. But that’s not exclusive; other states like Arkansas, Pennsylvania and even relatively non-polarized Rhode Island have also made appearances.
I think (said he, hopefully not over-simplifying) is that while election policy fights are more likely to occur as relative polarization increases, the fact that polarization exists everywhere means that compromise on these issues is more difficult overall. That is, while relatively less-polarized states may be able to find common ground on some policies, the fact that election debates have both a policy aspect (are we right?) and a political aspect (will we win?) makes them more likely to recur and less likely to be settled amicably.
[One question/outlier I haven’t yet been able to get my head around – why Rhode Island, which is less polarized but still polarized – was able to enact voter ID. I’ll puzzle that one – feel free to chime in below with a comment if you have an answer!]
Still, this data is illuminating with regard to the impact of partisanship across states – and I look forward to digging in further as time goes by. Thanks to Shor and McCarty for compiling and sharing the data – I guess sometimes Twitter is right!