Self-Interest, Ideology, and Logrolling in Congressional Voting

Abstract

LAWS may be passed because of self-interest or because of ideology. All national laws are ultimately passed by Congress; therefore, an analysis of the factors which determine the way in which congressmen vote can be used to determine the extent to which each of these factors is involved in passage of legislation. Because of the development of statistical tools such as logit analysis, which enable the analyst to handle situations in which the dependent variable is dichotomous, determinants of voting have recently been examined using roll-call voting data. The basic technique in this work has been to define the vote by a congressman on a bill as the dichotomous dependent variable and to use economic factors associated with the district as independent variables. But if this research is to proceed, it is necessary to separate out the factors-self-interest, logrolling, and ideology-which actually determine voting. This separation is the purpose of this paper. Kau and Rubin' and Silberman and Durden2 have analyzed voting on minimum wages; Danielsen and Rubin3 have examined voting on energy issues; Davis and Jackson4 have examined voting on income redistribution; and Kau and Rubins have examined the effect of public-interest lobbies such as Common Cause on the legislative process. Thus, statistical analysis of roll-call voting has been, and is likely to continue to be, a useful tool. This work in economics has differed somewhat from related work by political