How post-electoral intraparty rank affects party unity in the Brazilian Chamber of Deputies

Within the fields of electoral studies and legislative politics, the interest of this study is the Brazilian electoral system and the unity of the parties it produces. Specifically, I ask how post-electoral intraparty rank affects party unity. I determine post-electoral intraparty rank by comparing deputies’ vote share of the total national vote count. By compiling a database of 48 roll-call votes of 37 Federal Deputies from São Paulo, I compare how often the deputies toe the party line to their vote share. I also test for the geographical concentration of votes in cases where I find it relevant. My hypothesis is that deputies elected with a low vote share will vote according to their party’s recommendation to a larger degree than those deputies with a strong electoral base. I find that, based only on roll-call vote analysis, the complete sample does not demonstrate a strong relationship between voting agreement and vote share (or post-electoral rank). However, by analyzing significant cases individually, I do find a basis for my hypothesis, as well as indicators of theoretical consistency in the sample. The basis is for the most part strengthened when controlling for vote concentration. I conclude that deputies whose largest electoral base is centered in cities seem to be more autonomous in their voting, most likely for ideological reasons rather than reasons motivated by pork-barrel spending