The subject of the partisan polarization of Congress came up in conversation recently, and along with it was the topic of redistricting and gerrymandered districts. That made me hunt up this paper (PDF) from Princeton's Nolan McCarty, UCSD's Keith Poole, and NYU's Howard Rosenthal, which debunks the notion that weirdly-drawn Congressional districts are a significant factor.
Both pundits and scholars have blamed increasing levels of partisan conflict and polarization in Congress on the effects of partisan gerrymandering. We assess whether there is a strong causal relationship between congressional districting and polarization. We find very little evidence for such a link. First, we show that congressional polarization is primarily a function of the differences in how Democrats and Republicans represent the same districts rather than a function of which districts each party represents or the distribution of constituency preferences. Second, we conduct simulations to gauge the level of polarization under various "neutral" districting procedures. We find that the actual levels of polarization are not much higher than those produced by the simulations. We do find that gerrymandering has increased the Republican seat share in the House; however, this increase is not an important source of polarization.
For what it's worth, when the Lege - or some appointed commission - gets around to drawing new lines, the main criterion I hope they use isn't competitiveness per se, but community of interest, and to a lesser extent compactness. The problem with valuing competitiveness is that you can simply glue together deep blue areas with deep red ones; not only is that unsatisfactory, as half the district will feel unrepresented at all times, it doesn't guarantee a moderate result - you may well get two candidates whose strategy is base turnout. Ironically, the much-maligned Austin-to-Houston CD10, which was drawn to be a solid red district, is basically what you'd get from prioritizing competitiveness. That's not my idea of good design. Whatever we'd wind up with in terms of competitiveness, I think we'd be much better served emphasizing communities of interest, and we'd get representation that's no more or less partisan than what we've already got.Posted by Charles Kuffner on March 06, 2009 to Show Business for Ugly People