Procedural and party effects in European Parliament roll-call votes

The article extends the standard spatial model of legislative voting to account for vote-specific party inducements and procedural differences. Focusing on voting in the 1999-2004 European Parliament, it finds evidence of vote-specific party inducements in a large share of the roll call votes. Furthermore, MEPs position themselves differently across procedures. As most roll call votes are taken on non-legislative votes, these estimates may overemphasize voting pattern on these votes and downplay voting pattern on legislative votes. As such, these estimates may be a poorly suited for studying within party heterogeneity on legislative votes.