Category Archives: Parties

Polarization in the West, 1996-2017

I previously posted new visualizations of political polarization in Southern American state legislatures in preparation for a conference honoring the work of legendary political scientist Keith T. Poole. Here’s those same plots for Western state legislatures from 1996-2017 (marked in 4 year intervals plus 2017 preliminary data). As always, polarization is measured as the distance between the Republican and Democratic party medians, averaged across the two chambers. Lines are colored according to which party is polarizing faster.

States in the West are the most polarized, and the fastest polarizing, according to our data. Colorado, California, and Arizona dominate the race to the poles, though other states too like Utah are quickly charging up the rankings.  Colorado only in the past few years has overtaken California for the title of the most polarized state legislature in the country. Hawaii is clearly an outlier, with a liberal Democratic party paired with a liberal Republican party (in the House).

In terms of asymmetric polarization, here too, with the exception of Colorado, Democrats and not Republicans have been polarizing in more states.

polarization_slopegraph.png

Here are the positions of Republican party medians in the West. They’ve polarized quickest in Colorado.

republican_slopegraph.png

The Democratic slopegraph is more dramatic. Dramatic falls are visible in almost every state except Alaska and Idaho.

democratic_slopegraph.png

Polarization in the South, 1996-2017

I’m working on new visualizations of political polarization in American state legislatures in preparation for a conference honoring the work of legendary political scientist Keith T. Poole. Here’s a slopegraph (inspired by Edward Tufte and powered by Thomas Leeper’s awesome R package) of polarization in Southern state legislatures from 1996-2017 (marked in 4 year intervals plus 2017 preliminary data). This was a period of intense transformation in the South, when the almost-fully Democratic-controlled legislatures transformed into Republican-dominated ones in just two decades. Polarization is measured as the distance between the Republican and Democratic party medians, averaged across the two chambers.

In every single state, the parties have been polarizing. And would you just look at Texas? It was the most polarized in 1996, and it’s only increased its lead in 2017.

The line colors represent whether Republicans or Democrats polarized faster in that state. And, in contrast to Congress, Democrats are polarizing faster more frequently than Republicans in the South, including Texas.

polarization_slopegraph.png

Here are the plots for the Republican and Democratic party medians in the South over this time period to give you a sense of how the parties changed. First the Democrats:

democratic_slopegraph.png

Now the Republicans:

republican_slopegraph.png

Updated Polarization Plot for 2015-2016

We plan to update our publicly accessible data to include the results of the 2014 election.

In the meantime, here is how the states stack up in terms of polarization. One big change has been the vast increase in polarization in Colorado, which nearly matches California’s polarization. Other rapidly polarizing states include Arizona, Texas, and Missouri.

average_polarization_2015.png

June 2015 Update to Shor-McCarty State Legislatures Data

Today I posted the individual, legislator-level ideology data as well as the aggregate state and chamber-level data for our state legislature ideology data. The data is free for public download and use. Please cite our data and paper if you use this in your academic work, and/or link back to us in other work.

We have extended the data collection through 2014, and we now have 20,783 unique state legislators in our data, as well as 1,816 chamber-years of aggregate data.

As with previous iterations, we have continued to spend a lot of time and effort cleaning up the data; there should be far fewer noise-related issues. But please let us know if you see particular problems.

You can find the individual data here and the state level data here.

Bugs should be reported to us.

The roll call data collection in this update has been supported financially by the Laura and John Arnold Foundation.

The New New York State Assembly Speaker is Pretty Unusual

Sheldon Silver, New York State’s iconic Assembly Speaker, was forced to resign after being charged with serious federal corruption charges. Bronx Democrat Carl Heastie is going to ascend to the position sometime on Tuesday, after his last competitor, Queens Assemblywoman Catherine Nolan, dropped out of the race to succeed Silver.

I tweeted on Saturday that I was surprised by this turn of events. This was after another competitor, Democratic Assembly Majority Leader Joseph Morelle (apparently the favored candidate of Governor Cuomo), had dropped out of the race.

I was surprised because Carl Heastie is fairly extreme ideologically. Yet almost all the attention in the discussion about the speaker’s succession has been about race, potential ethical issues, and a real or imagined power play between Governor Cuomo and Mayor de Blasio.

Our state legislative ideology data set provides me with the data for this post. The current release of the data has data into 2013, but we are currently working on extending that data set into 2015. I don’t have the newest members serving in 2015, but they are relatively few as the chamber isn’t very competitive. So I’m just using the scores and composition of the chamber as of 2014.

Sheldon Silver is in the most liberal fifth of his party in the Assembly. Nolan has basically the same ideological profile as Silver. In contrast, Morelle is a little to the right of the median Democrat. Carl Heastie, on the other hand, is the fifth most liberal Democrat (only Weinstein, Rosenthal, Glick, and Robinson to his left) in the Assembly, out of a total of 106. And it’s not like Silver, Nolan, or even Morelle are hardline conservatives. The New York State Democratic party is amongst the most liberal in the country, alongside California and Vermont’s Democrats.

This is a puzzle because I’d expect New York Democrats to pick someone closer to their ideological center. This should be due, crudely speaking, to the median voter theorem. A simple majority-rule election should have the property of privileging centrist candidates. Just look at the 113th Congress US House leadership team of John Boehner, Eric Cantor and Kevin McCarty, who were just about at the center of their party in the House.

A recent paper by Stephen Jessee and Neil Malhotra shows empirical evidence for this notion: party leaders in Congress tend to be not very far from the center, especially in comparison to their competitors for the offices (Democrats do shade somewhat to the left and Republicans to the right of their party medians). In this case, however, the winning candidate is especially far relative to not only the party as a whole, but in comparison to his announced competitors.

What’s going on here? Are states that different from Congress? Or is something peculiar about New York in particular? I’m not sure, but events like this get me thinking about new research projects …

 

Asymmetric Polarization in the State Legislatures? Yes and No

Last week I showed how American state legislatures are largely polarizing over the past 15 years or so; the parties are getting ever more extreme and distant from each other, above and beyond the levels of the past. I ended that post with a question: “But which parties are driving this polarization at the state level? Are both parties at fault, or is one becoming more extreme compared to the other? That is, is state legislative polarization symmetric or asymmetric?” I will tackle this subject in my this post.

When we look at Congress over the past 20 years, we can clearly see that–in both the US House and Senate–the Republican party has gotten more extreme over time relative to the Democrats (though in the House Democrats have polarized to a smaller degree as well). This is a familiar story of asymmetric polarization. In fairness, Democrats’ move in the liberal direction started earlier than Republicans: the 1940s versus the mid 1970s. Still, in recent years, Congressional Republicans have unquestionably moved further, faster.

party_chamber_years_congress_cs

The data and method that Nolan McCarty and I have developed shed light on trends in America’s state legislatures. Let’s look at the picture graphically, plotting party medians over time, separately for each chamber (click on the graphic for a higher-resolution version). By convention, more positive scores represent more conservative preferences, and more negative scores represent liberal preferences.

party_chamber_years

Looking across the states, Republicans on the whole are clearly polarizing faster than Democrats. In 57 of the 99 state legislative chambers, they are getting more conservative over time, while in 47 chambers Democrats are getting more liberal. In 26 chambers Democrats are actually getting more conservative (eg, depolarizing), while the converse is true in 20 chambers for Republicans where they are getting more liberal. In 26 chambers Democrats are roughly stable and the same is true in 22 chambers for Republicans.

But what the data clearly reveal is that states are wildly diverse. In some states like Tennessee and Colorado, Republicans are getting more extreme in recent time, while Democrats are not changing much. But in other states like Idaho, Mississippi, and California, it is Democrats who are largely responsible for the states’ recent polarization. And finally, there are states like Texas, Missouri, and Nebraska where both parties are polarizing roughly equally and simultaneously.

So the polarization story is similar in some ways in state legislatures than in Congress: Republicans are leading the charge to the ideological poles on average. But it’s different, too: the average story obscures lots of differences across states. State polarization trends thus underline the usefulness of studying state legislatures as a laboratory for political observers: there’s just lots of variation to work with in trying to understand what causes what. And so we should look to state experiences to see whether reforms in areas like redistricting, primaries, campaign finance, and so on do anything to mitigate polarization, and whether some reforms might have unintended consequences that make it worse.

 

Polarization Trends in American State Legislatures by Chamber

The political parties in Congress are increasingly polarized in ideological terms. This is largely driven by replacement rather than adaptation; that is, moderates are increasingly leaving Congress, and being replaced by ideological extremists.

The plot below shows the difference between the Republican and Democratic party medians using Poole et al’s common space NOMINATE scores, for the 103rd (1992-1993) through the 112th (2011-2012) Congresses. Under this common measure, a larger gap between the centers of both parties indicates a greater level of polarization.polarization_congress_years_cs

Both House and Senate are polarized (the distance is greater than zero), and they are getting more so over time. The US House in particular is both more polarized in terms of level and polarizing faster in terms of trend relative to the US Senate.

What about American state legislatures? It’s important to nail down these numbers because we need to know where we stand to find out if polarization is leading to political gridlock and dysfunctional policy. We also need a barometer of polarization to find out whether reforms like opening up primaries, taking redistricting away from politicians themselves, term limits, and so forth can do anything about this yawning gap between the parties. And since there are 50 state legislatures, we might find answers to these questions more quickly and definitively than we can with Congress, of which we only have one.

Earlier in this blog I showed evidence that most state legislatures are in fact quite polarized, and a significant number of them are even more polarized than Congress. The data underlying these figures can be found here, and the paper explaining how Nolan McCarty and I came up with the numbers can be found hereNow we’ll take a more detailed look at the state polarization trends for all 50 states over time. The plot below shows the distances between the party medians for all 50 states over approximately the same time period, roughly 1996-2010.

polarization_chamber_years

As with the US Congress, all 99 state legislative chambers (Nebraska has a single chamber commonly referred to as the Unicam, which I term a Senate here) are polarized. In 59 of those 99 chambers, the parties are getting more distant from each other. In 16 of them, the parties are actually depolarizing or getting closer. Finally, in 24 chambers, the parties are roughly stable in relation to each other.

However, in most states, unlike in the US Congress, the upper (Senate) chamber is typically more polarized than the lower (House or Assembly) chamber. On the other hand, the lower chamber is polarizing faster in more states than the upper chamber. It is not yet clear why these differences should exist.

The top 10 fastest polarizing chambers, in order, are the Idaho Senate and House, the Missouri Senate, the Arizona Senate, the Hawaii Senate, the Colorado Senate, the Tennessee House, the Nevada Senate, the Maryland Senate, and Mississippi Senate.

At the same time, California retains its title as the most polarized state legislature in the country. It has even managed to move up a couple of notches in the past 15 years. 

Another notable state is Nebraska, whose Unicam is amongst the fastest polarizers in the country, despite the fact that it is nonpartisan by law in the chambers and at the voting booth. Seth Masket and I show in a paper how parties in the state have overcome this powerful prohibition to work as cohesive, disciplined units–just like other states.

But which parties are driving this polarization at the state level? Are both parties at fault, or is one becoming more extreme compared to the other? That is, is state legislative polarization symmetric or asymmetric? I will tackle this subject in my next post.

Interestingly enough, a few state chambers are actually depolarizing: the parties are actually coming closer together. The fastest depolarizing state chambers, in order, are the Wyoming House, the Oregon Senate, the Alaska Senate, the Ohio Senate, and the North Carolina Senate. This is completely unheard of in recent years in Congress.

NB: The scales of the two plots aren’t comparable because they are taken from two separate data sources. However, in technical terms, they are both common space measures which disallow individual legislator ideological drift in order to facilitate an apples-to-apples comparison.