Political scientists have long used roll call votes cast by members of the U.S. Congress to plot legislators on the liberal-conservative (Lib-Cons) dimension along which most legislative politics in our nation’s capitol takes place. Here, I provide similar information for members of the Texas House of Representatives for the 2009-2010 legislative session, ranked from 1 (most liberal) to 150 (most conservative), calculated using the DW-NOMINATE procedure developed by Professors Keith Poole and Howard Rosenthal.
While there are a host of interesting insights that can be drawn from these data, here I restrict my comments to four:
First, indicative of the high degree of partisan polarization currently present in the Texas House (a topic I will explore in a future entry), there exists no overlap among the Democratic and Republican representatives. The most conservative Democrat (Allan Ritter) is still significantly more liberal than the most liberal Republican (Tommy Merritt).
Second, three of the four most liberal Republicans will no longer be members of the Texas House in January 2011 (Delwin Jones and Tommy Merritt were defeated in the Republican primary, and Brian McCall resigned), while one of the four most conservative Democrats (Charles “Chuck” Hopson) switched to the Republican Party after the 2009 regular session. These three departures and one switch reflect a continuation of the gradual extinction of conservative Democrats and liberal Republicans that has taken place over the past 30 years in Texas.
Third, in contrast to his predecessor (former Speaker Tom Craddick, ranking of 125), Speaker Joe Straus, a Republican, has a relatively liberal Lib-Cons Score (ranking of 84). Only nine other Republicans possess a Lib-Cons Score that is lower (more liberal) than Straus’, while 65 have higher scores (more conservative). Given the origins of Straus’s election as speaker (i.e., based on the support of most Democrats and a handful of Republicans) this location is not surprising, but does leave him potentially vulnerable in the January 2011 speaker’s race to a more conservative challenger. (That said, at present Straus is expected be re-elected as speaker).
Fourth, representatives from the Houston area are spread across the Lib-Cons spectrum (in the table, Houston-area Democrats are in blue and Republicans in red). Some of the House’s most liberal (Garnet Coleman, Jessica Farrar) and conservative (Randy Weber, Debbie Riddle) members are from the Houston area; Weber is ranked as the most conservative member of the House (the most liberal member is Yvonne Davis of Dallas).
Most Liberal Representatives
| Ranking | Representative | Lib-Cons Score | Political Party | Intra-Party Group |
|---|---|---|---|---|
| 1 | Yvonne Davis | -0.712 | Democrat | Very Liberal |
| 2 | Abel Herrero | -0.702 | Democrat | Very Liberal |
| 3 | Garnet Coleman | -0.701 | Democrat | Very Liberal |
| 4 | Jessica Farrar | -0.701 | Democrat | Very Liberal |
| 5 | David Leibowitz | -0.700 | Democrat | Very Liberal |
Most Conservative Representatives
| Ranking | Representative | Lib-Cons Score | Political Party | Intra-Party Group |
|---|---|---|---|---|
| 146 | Dan Flynn | 0.868 | Republican | Very Conservative |
| 147 | Debbie Riddle | 0.873 | Republican | Very Conservative |
| 148 | Linda Harper-Brown | 0.882 | Republican | Very Conservative |
| 149 | Sid Miller | 0.885 | Republican | Very Conservative |
| 150 | Randy Weber | 0.900 | Republican | Very Conservative |
Download the full table with information on all 150 representatives (PDF).
Methodology
Representatives who cast roll call votes during the 2009-10 session are listed below, including those who have resigned since the last regular session; Speaker Joe Straus’ comparable Lib-Cons Score from the 2007-09 session is used because, under House custom, most speakers rarely cast votes. The theoretical range for this scale is -1.00 (extreme liberal) to 1.00 (extreme conservative). The 150 representatives are arrayed in the full table based on where their roll call vote behavior locates them on the liberal-conservative dimension which dominates legislative voting behavior in Texas, with the most liberal representative ranked “1” and the most conservative representative ranked “150.”
As a heuristic, the members of each party are divided into six distinct intra-party groups (three within each party) based on the criteria below. It is important to keep in mind that these Lib-Cons scores are statistical estimates, and thus have a small amount of error surrounding them. This suggests that where there exist small to moderate differences among legislators (e.g., less than 0.2), we should consider those representatives to not differ substantively from each other in terms of their location on the liberal-conservative ideological dimension.
Democrats
- Very Liberal: A Lib-Cons Score that is more than one standard deviation lower (more liberal) than the mean for the Democratic Party delegation.
- Liberal: A Lib-Cons Score that is within one standard deviation (above and below) of the Democratic Party mean (-0.34).
- Conservative: A Lib-Cons Score that is more than one standard deviation higher (more conservative) than the Democratic Party mean.
Republicans
- Liberal: A Lib-Cons Score that is more than one standard deviation lower (more liberal) than the mean for the Republican Party delegation.
- Conservative: A Lib-Cons Score that is within one standard deviation (above and below) of the Republican Party mean (0.67).
- Very Conservative: A Lib-Cons Score that is more than one standard deviation higher (more conservative) than the Republican Party mean.
Mark P. Jones is a Baker Institute Rice scholar, the Joseph D. Jamail Chair in Latin American Studies and chair of the Department of Political Science at Rice University.