With health care reform in the hands of the Senate, Joe Lieberman’s threatened filibuster is making headlines. This raises a more general question: why do Senators filibuster?
bq. This paper contributes to the growing empirical literature on filibusters by examining the factors that are associated with individual-level filibustering behavior. We focus particularly on the behavior of senators in the latter part of their careers, using impending retirement as analytical leverage to determine whether decisions to engage or not in dilatory parliamentary practices are driven more by narrowly drawn considerations of instrumental utility or by compliance with institutional norms of deference and cooperation. Using data from 1975 to 1993 and employing multivariate models that allow us to control for other relevant factors, we find only limited support for a narrowly rational model of Senate “followership.” In the course of our enquiry, we clarify the notion of legislative norms, integrate our study with recent interdisciplinary scholarship on the evolution of cooperative behavior and consider how leadership can be exercised in environments largely bereft of formal leadership resources.
That’s from research by Lauren Bell and Marvin Overby (gated; ungated).
The hypothesis is that filibustering is costly and is therefore is more attractive to retiring senators, who have a shorter time horizon and therefore would pay lower costs. More crudely: retiring senators can indulge their personal idiosyncrasies without suffering the same opportunity and reputational costs. An alternative hypothesis is that senators would obey norms of deference and courtesy — norms which could be even more firmly inculcated in retiring senators, most of whom are senior — and so impending retirement should not affect filibustering.
The data are the 227 senators who served in the U.S. Senate from 1975-1993. The model, which controls for several other factors beside imminent retirement, finds:
* Minority party senators are more likely to filibuster. No surprise, but naturally this is a necessary control variable and a comforting findings.
* Ideologically extreme senators are more likely to filibuster. This also makes sense.
* Being from a small state makes no difference.
* Most importantly, imminent retirement does not matter. Only when the sample is limited to senators whose entire careers took place within the 1975-93 interval does there appear to be an effect of retirement (but this is based on only a small number of observations — 16 senators).
The model doesn’t predict much of the variance in the data, which suggests that a lot of filibustering behavior is due to other, and perhaps difficult to measure, factors.
This last finding leads Overby and Bell to write:
bq. The fact that fewer than 20 percent of senators opt to lead filibusters in their last Congress strikes us as underwhelming and indicates, at very least, that retiring senators do not entirely and en masse disregard the chamber’s norms of comity and cooperation in order to pursue narrowly personal legislative goals.
Caveats abound in applying this research to Lieberman. The data stop in 1993, for one. Most importantly, there is no reason to think that this finding — that norms trump rational self-interest — applies to Lieberman in particular. Maybe his behavior is driven by revenge or personality. These things are hard to measure and so they don’t figure in much political science research generally or on the filibuster in particular.
But this research gives us some framework for thinking about Lieberman’s apparent decision. (And we should emphasize apparent; perhaps he is bluffing or strategically threatening.) In fact, it makes his decision all the more curious. He is not a minority party member. He is not ideologically extreme relative to the chamber. (Perhaps more so relative to the median Democratic senator.) However, although he has not announced any plans to retire, perhaps he sees himself as electorally threatened and therefore sees fewer costs to obstruction. Here’s one poll that suggests the threat.
So perhaps, in a way, the finding that retirements do matter — at least among those 16 senators whose careers were fully encompassed in the Overby and Bell data — applies to Lieberman. If he believes he is nearing the end of his career, there is less reason not to pursue a more personal agenda. This, of course, does not explain why Lieberman’s agenda on health care seems more conservative than it was in the past.