Conference Committees and Conference Appointers

Prior work has examined the independent influence that conference committees have on legislative outcomes, finding that conferences maximize their policy benefits when receiving majority support in both chambers (Tsebelis and Money Reference Tsebelis and Money1997; Vander Wielen Reference Vander Wielen2010). Conferees commonly receive support from their chambers due to the quality of information they use to construct stable outcomes and reduce the likelihood of stalemate (Rogers Reference Rogers2001; Rybicki Reference Rybicki2003). Conference committees broker deals on legislation, bargaining across chambers to limit the risk of failure, elucidating why the parent chambers delegate authority to conferees (Vander Wielen Reference Vander Wielen2013).

The unamendable nature of conference reports aligns prima facie with partisan models of legislative organization, which suggest that institutional characteristics are an important source of party power (Cox and McCubbins Reference Cox and McCubbins2005). Spatially, party leaders can utilize conference reports to promote extreme legislative policies if the conferee proposal is preferable to the median than the status quo. In Congress, the Speaker of the House and Senate Majority Leader control conferee appointments, and can therefore select party loyalists to broker a deal ideologically consistent with their preferences (Lazarus and Monroe Reference Lazarus and Monroe2007).Footnote ⁵ Accordingly, congressional conferees largely abide by majority party preferences (Vander Wielen and Smith Reference Wielen, Ryan and Smith2011). In state legislatures, the majority party in every chamber holds a numerical advantage in conference appointments. This serves the majority party in seeking their favored policy outcome, which in a unidimensional setting is the majority party median. Unless the state legislative chamber is perfectly homogeneous ideologically (which is unlikely e.g., Shor and McCarty Reference Shor and McCarty2011), the majority party median will differ from both the chamber and minority party medians. Like congressional conference delegations, I expect a baseline level of majority party influence over state legislative conference delegations (Nagler Reference Nagler1989; Vander Wielen and Smith Reference Wielen, Ryan and Smith2011). This unconditional effect should lead to conference delegations ideologically resembling the majority party median, resulting in delegation compositions favoring the majority party:

Hypothesis 1 runs counter to Krehbiel (Reference Krehbiel1991; Reference Krehbiel1993), who challenges the partisan nature of conference committees. In an informational context (Krehbiel Reference Krehbiel1991), partisanship has no bearing on the composition of conference delegations. Instead, policy expertise derived from expert members of relevant standing committees dominates bicameral negotiations. Consider Massachusetts’ appointment of Republican State Representative Kimberly Ferguson to a conference delegation in 2019 tasked with coalescing various proposed funding increases for education.Footnote ⁶ With experiences as Ranking Minority Member on the Education Joint Committee, Ferguson indicated upon appointment to the delegation the existing “bipartisan commitment to education” (Sentinel and Enterprise 2019). Other legislators echoed similar sentiments, with House Minority Leader Bradley H. Jones noting that “As a member of the Foundation Budget Review Commission whose 2015 report provided the impetus to revisit the state’s education funding formula, Representative Ferguson understands the key issues that need to be addressed… to ensure that all Massachusetts students have access to a quality education” (Massachusetts House Republican Caucus 2019). Broadly, informational conditions suggest that conferees selected are more representative of the chamber’s median voter (cf. Hall and Wayman Reference Hall and Wayman1990). This leads to my second hypothesis:

Following Krehbiel, the conditions under which state legislative conferees follow the majority party’s preferences are unclear. First, while party leaders may instruct conferees when they go to conference, these instructions are not binding in any chamber. Second, although congressional conferees mostly follow majority party desires, this may be a result of the majority party leadership having total discretion over who serves on the conference committee. Most state legislatures follow Congress by unilaterally bestowing the majority leadership conference appointing rights.Footnote ⁷ That said, several chambers’ legislative rules endow the lieutenant governor or minority party leadership with appointing rights whereby these actors can assign a single or multiple legislators to the conference delegation.Footnote ⁸ For example, Illinois’ House of Representatives Rule 73 stipulates that “Each conference committee shall be comprised of five members of the House, three appointed by the Speaker and two appointed by the Minority Leader…” (Illinois House of Representatives 2015, 46). Figure 1a, b provide visualizations of conference appointing rules by state legislative chamber across the United States. In total, 14 (4 lower and 10 upper) state chambers have minority appointing rights. These rules were coded from the National Conference of State Legislatures (National Conference of State Legislatures 1998) and further confirmed by examining chamber rules. Appendix B provides a detailed listing of state conference committee appointer rules.

Figure 1. (a) State lower chamber conference committee appointers. (b) State upper chamber conference committee appointers.

When majority party leaderships decide to engage in post-passage bargaining in legislative chambers where the minority party influences conferee selection, they are likely aware that minority appointers will pursue their preferences. As a result, the majority leadership likely cedes some control over conference delegation composition when forced to collaborate with minority leaders. This expectation is similar to how relevant majority party standing committee members can interfere with majority leadership goals in conference, as common practice is to appoint members from the standing committees or subcommittees with jurisdiction over the bill (Longley and Oleszek Reference Longley and Oleszek1989; Smith Reference Smith1988).Footnote ⁹ Once in conference, standing committee conferees can use their agenda-setting abilities to shift legislation towards their preferences (Vander Wielen Reference Vander Wielen2010), while also utilizing their “ex post veto” rights to revert changes made on the chamber floor (Shepsle and Weingast Reference Shepsle and Weingast1987). Often, rogue standing committee conferees are high-demanding legislators seeking to modify legislation to better satisfy their (and their constituencies’) preferences for electoral gain (Weingast and Marshall Reference Weingast and Marshall1988).

For minority party leaders, they likely share similar goals to individualist majority legislators, seeking to have their ideological preferences satisfied for electoral purposes. Additionally, minority leaders possess a collective political incentive when obstructing the majority party leadership’s goals in conference (Lee Reference Lee2009). The minority party’s linked electoral fate encourages its members to cooperate against the majority to discredit the majority leadership’s agenda by being less willing to collaborate with the majority party in pursuit of partisan collective gain (Koger and Lebo Reference Koger and Lebo2017; Lee Reference Lee2016). Mainly, compromise on average is a negative outcome for the minority party, because if they cooperate with the majority, they undercut their future electability (Gilmour Reference Gilmour1995). Even if they receive concessions from the majority in conference to form the winning coalition, the majority still executes its mandate and receives the lion’s share of the rewards (Balla et al. Reference Balla, Lawrence, Maltzman and Sigelman2002; Groseclose and Snyder Reference Groseclose and Snyder1996). Because of this, I expect minority leaders to appoint conferees who are ideologically dissimilar from the majority leadership’s preferences.Footnote ¹⁰ Substantively, I anticipate that in legislatures where the minority has the ability to influence conference appointments, conference delegations resemble the chamber median more so than the majority party median:

Data and Methods

To analyze how variation in conference appointer affects majority party control over delegation composition, I created a new time-series cross-sectional data set on conference delegations from 2005 to 2016. The data collection starts in 2005; however, several states only report conference committee actions in recent years. For example, Florida and West Virginia only maintains conference delegation information from 2011 to present, whereas Kentucky starts in 2008.Footnote ¹¹ Iowa, Louisiana, and Oregon all report from 2007 onward. Conference delegation information was scraped from state legislature web archives, as most states provide detailed bill histories of when conferences and conferees were appointed. For those which did not, web archives were searched for written and audio documentation of conference committees. Conference delegation information was then transcribed from these materials.Footnote ¹²

This data set contains all conference delegations for both lower and upper chambers. In situations where one chamber appoints conferees and the other does not, no conference committee convenes. However, given that I am focused on the appointing rights of majority parties, these cases are retained for analytical leverage in testing how varying institutional features impact majority control over legislative outcomes.Footnote ¹³

Despite most states using conference committees, several do not. Most known is Nebraska’s unicameral legislature. Additionally, New Jersey and Rhode Island do not have conference committees to prevent legislative gridlock. Other states have codified conference committees or similar institutions, but they serve specific purposes or are seldom utilized. For example, Delaware only uses a joint appropriations committee for budget bills, whereas Arkansas, Connecticut, and New York have rarely used conference committees in the past century, with none occurring throughout the scope of my analysis.Footnote ¹⁴

Maine and Ohio have bill histories with insufficient documentation to discern who served on the conference committee.Footnote ¹⁵ Additionally, Oklahoma’s legislature uses conference committees, but is idiosyncratic in its use of permanent standing conference committees for legislation.Footnote ¹⁶ Broadly, I exclude from the analysis those delegations where I was unable to recover conference membership. The resulting data comes from 41 states and 82 legislative chambers across 942 chamber-years. In total, I tally 16,541 lower and 16,783 upper chamber conference delegations, resulting in 33,324 total groupings.

Figure 2 shows the within-chamber changes in conference delegation trends for noncommemorative bills for all states which appointed named conference delegations between 2005 and 2016.Footnote ¹⁷ Notably, states have employed conference committees at consistent rates over time.Footnote ¹⁸ As expected, conferencing trends for lower and upper chambers within a state are quite similar over time. In most circumstances, the opposite chamber appoints a conference delegation when the originating chamber does. Additionally, states have employed conference delegations at consistent rates over time, with few states appointing conference delegations regularly. Hawaii employs conference delegations most often, with over 86% of their passed legislation going to conference.Footnote ¹⁹ Hawaiian legislators regularly serve on several conference committees concurrently, overwhelming legislators who have been quoted as needing “to be at four different places right now” during an ordinary legislative day (Blair Reference Blair2011). In contrast, most states appoint conference delegations for less than 10% of passed bills. Appendix B offers information on the number of conference delegations appointed for each chamber.

Figure 2. Percentage of conference delegation bills in state legislatures by chamber, 2005–2016.

Note. Figure 2 slightly underrepresents the total number of conference delegations, as a single bill can have multiple conference committees. Oklahoma’s House of Representatives trendline stops at 2010 to match Oklahoma’s Senate trendline. Additionally, states that have no bills in a given year are dropped from Figure 2. Those states with biennial legislatures are connected by every two years (e.g., Montana 2005 and 2007).

To examine the relationship between conference committee appointment rights and chamber ideology for evidence of majority party bias, I focus on the median legislator in each delegation. However, standard difference-of-median tests for conference delegations are an insufficient method given that most delegations have small memberships (typically between three and five per state legislative chamber), inhibiting non-parametric difference-of-median tests (Freidlin and Gastwirth Reference Freidlin and Gastwirth2000). To circumvent this complication, I follow the empirical strategy of Vander Wielen and Smith (Reference Wielen, Ryan and Smith2011). They note that “if the number of conference delegations included in the analysis is large, it follows that the distribution of differences between the conference delegation and chamber medians… would have a mean of zero if conferees are indeed representative of the parent chamber” (279). By constructing a distribution of differences across medians, I can aggregate the delegations and plot them for a descriptive visualization of majority party influence in conference delegation composition. The resulting visualizations permit an analysis of whether the distribution of conference delegations deviates in a statistically significant manner from the expectations of my hypotheses. There would be support for hypothesis 1 if the mean of the delegation distribution equals the majority party median; evidence for hypothesis 2 would exist if the mean equals the chamber median.Footnote ²⁰

Similarly, I plot the distribution of differences between majority leadership appointed conferees and minority party influenced conferees to illustrate variation in majority party control conditional on conference appointer. To reiterate hypothesis 3, I expect conference delegations appointed solely by the majority party to be closer ideologically to the majority party median than minority influenced delegations. That is, minority party appointments limit majority party control over conference committees by widening the ideological distance between the conference delegation and majority party medians. Twelve state legislative chambers possess minority appointing rights throughout my data set, totaling 3,056 conference delegations across 127 chamber-years. These chambers are Alabama’s Senate (in 2011 when the lieutenant governor and Senate majority were of differing parties), Illinois’ House and Senate, Iowa’s House and Senate, Kansas’ House, Massachusetts’ House and Senate, Mississippi’s Senate (from 2005 to 2010), New Mexico’s Senate, South Carolina’s Senate, and Washington’s Senate.Footnote ²¹

I facilitate comparisons of lower and upper chamber delegations cross-state, cross-chamber, and over-time by measuring ideology on the dominant Left–Right unidimensional spectrum most specific to interparty conflict (e.g., Poole Reference Poole2007; Poole and Rosenthal Reference Poole and Rosenthal1985). Mapping state legislators onto a single dimension allows for clear comparisons of the conference delegations relative to both the majority party and chamber medians. Additionally, higher order dimensions commonly pertain to parochial interests as opposed to partisan conflict (Miller and Schofield Reference Miller and Schofield2003). My analysis uses Shor and McCarty’s (Reference Shor and McCarty2011) common-space scores for state legislatures and legislators. These ideal points are generated from the fusion state-level roll call voting data and surveys of state legislative candidates, allowing scholars to make comparisons of interparty heterogeneity. For ease of interpretation, I rescale the Shor-McCarty scores so that the majority party’s ideology within the chamber (whether Republican or Democrat) corresponds to positive values.

I supplement the distribution of ideological differences by modeling the contrasts between conference delegation and majority party medians. I test hypothesis 3 with the following generalized equation, estimating ordinary least squares models with two-way random effects of the following form (Smithson and Merkle Reference Smithson and Merkle2013):

$$ {\displaystyle \begin{array}{cc}\mathrm{Conference}\ \mathrm{Ideolog}\mathrm{y}-& \hskip-1em \mathrm{Majority}\ \mathrm{Party}\ \mathrm{Ideolog}{y}_{it}=\beta \mathrm{Minority}\ \mathrm{Conference}\ \mathrm{Appointe}{\mathrm{r}}_{it}\\ {}& \hskip-30em +{\gamma}_i+{\delta}_t+{\rho}_{it}+{\epsilon}_{it}\end{array}} $$

where $ \mathrm{Conference}\ \mathrm{Ideolog}\mathrm{y}-\mathrm{Majority}\ \mathrm{Party}\ \mathrm{Ideolog}{\mathrm{y}}_{it} $ is a continuous variable computed as the difference in Shor and McCarty (Reference Shor and McCarty2011) common-space scores between the median conferee’s ideology and the median majority party legislator’s ideology. $ {\gamma}_i $ represents state random effects to account for unobserved heterogeneity across states and $ {\delta}_t $ represents session random effects to sweep out differences common to a legislative session. $ {\epsilon}_{it} $ is the error term. By incorporating these random effects, conference delegations are treated as being nested within states and legislative sessions.Footnote ²²

My main independent variable $ \beta \hskip0.4em \mathrm{Minority}\ \mathrm{Conference}\ \mathrm{Appointe}{\mathrm{r}}_{it} $ is a dummy variable equal to one if the minority party in a state legislative chamber has influence over the conference appointing process in a given year, and 0 if the state chamber’s majority unilaterally selects conferees. A negative value from this variable would suggest that minority party appointments limit majority party control over conference committees by broadening the ideological gap between conference delegation and majority party medians. Importantly, conference appointing rules do not vary within-state across my data set. That is, there are no state legislative chambers from 2005 to 2016 that switch their rules from the majority party unilaterally appointing conferees to minority influence, or vice versa.Footnote ²³

$ {\rho}_{it} $ controls for chamber-level factors that might influence the relationship between parties and conferees. First, I control for the heterogeneity of preferences across and within political parties from chamber to chamber. I measure the ideological distance between parties in state legislative chambers by using the Shor and McCarty (Reference Shor and McCarty2011) interparty heterogeneity measure which is equal to the average distance between the median ideal points of Republican and Democratic legislators in each chamber. I gauge the diversity of preferences within the chamber by using Shor and McCarty’s (Reference Shor and McCarty2011) intraparty heterogeneity indicator, which is the standard deviation of majority party legislator’s ideal points. Second, I account for the level of professionalism in the state legislature. There is likely a direct correlation between the professionalism of the legislature and the partisanship of legislators, whereby highly professionalized legislatures likely have legislators with stable partisan preferences (Battista and Richman Reference Battista and Richman2011; Fiorina Reference Fiorina1999; Ryan Reference Ryan2014). I capture each state’s professionalism with the Squire Index (Squire Reference Squire2017), which is a weighted combination of salary, days in session, and staff per legislator relative to members of Congress.Footnote ²⁴ Lastly, I control for political factors like intercameral agreement and disagreement by estimating separate models with binary variables equal to one for when the lower and upper chambers are unified or divided. Party leaders undoubtedly consider the preferences of the opposing chamber when deciding on delegation composition since a majority of both chambers must agree on the conference report.