The assumption that increased transparency improves political accountability is widely accepted. However, little is known about how government-targeted transparency affects the behaviour of elected representatives. Using a purposely created dataset, this paper will test whether disclosure-induced transparency affects MPs behaviour by analysing the outside jobs held by politicians subjected to different types of disclosure regulations. Building on existing research, I hypothesise that greater scrutiny about outside earnings reduces incentives to pursue side jobs, and that this is stronger amongst electorally vulnerable MPs, namely those seeking re-election and facing high political competition. Additionally, I argue that private sector side jobs, which are most unpopular with the electorate, should be expected to decline most when subjected to increased transparency. The analysis utilises a novel dataset on the extra-parliamentary behaviour of MPs from the German Bundestag and 16 State Parliaments, spanning over 40 legislative periods in the last two decades, and covering the moonlighting activities of over 30,000 legislator/year cases. The results have implications for our understanding of effective government-targeted transparency, political blame avoidance, legislative behaviour and electoral accountability.