We examine the labor supply of politicians using data on Members of the European Parliament (MEPs). We exploit the introduction of a law that equalized MEPs’ salaries, which had previously differed by as much as a factor of ten. Doubling an MEP’s salary increases the probability of running for reelection by 23 percentage points and increases the logarithm of the number of parties that field a candidate by 29 percent of a standard deviation. A salary increase has no discernible impact on absenteeism or shirking from legislative sessions; in contrast, non-pecuniary motives, proxied by home-country corruption, substantially impact the intensive margin of labor supply. Finally, an increase in salary lowers the quality of elected MEPs, measured by the selectivity of their undergraduate institutions.
That is from this new paper by Fisman et al.