A lame duck session of Congress occurs when legislators meet after an election has been held but before the next Congress has taken office. Lame duck sessions are often criticized by the victorious party in the election, and a common critique is that the lame duck members — undisciplined by electoral constraints — vote irresponsibly. There are subtle but statistically significant differences between voting patterns in regular and lame duck sessions, as revealed by analysis of over 50,000 House and Senate roll call votes.During a lame duck session, members are slightly less likely to side with their own parties and less likely to vote at all. These patterns persist in very lame duck sessions — those that take place following the loss of majority status within a single house. In these sessions, however, a new pattern emerges: House members become more likely to cast bipartisan votes and Senators become less likely to do so. Beyond these voting patterns, it is difficult to say whether members vote more or less “responsibly” during lame duck sessions of Congress. Our analysis supports the primary findings of the existing literature on lame ducks. Past studies have found lame duck legislators to be less likely to indulge most special interests, but others suggest they may be more likely to indulge one particular special interest: their next employers. In this study, we explain how incentives change for lame duck legislators, briefly review past research on lame ducks, and present our statistical findings that support and add to the existing literature.