In recent years, several national parliaments have introduced stricter rules for the disclosure of additional sources of income earned by their legislators. In this context of better data availability, the phenomenon of moonlighting politicians (legislators who pursue paid or unpaid jobs next to their political mandate) has attracted increasing public and scientific attention. Since 2011, also the European Parliament (EP) requires its parliamentarians to make their additional earnings public if they exceed a certain threshold. So far, however, the determinants of varying numbers of outside jobs and associated ancillary income have not been analyzed systematically for the EP. Building on a new dataset on moonlighting activities of all MEPs holding a mandate during the 7th term of the institution (2009-2014), this paper seeks to fill this research gap. Specifically, the paper assesses the extent to which ideology, education, experience and gender help to account for varying degrees of moonlighting among MEPs. On a general level, our findings contribute to a better understanding of the factors that affect the quality of democratic representation in the European Parliament.
