While legislative committees have considerable scholarly attention, committee chairs have received little attention, particularly in terms of their influence on legislative outcomes, despite having unique agenda-setting power. This study argues that which party controls committee chairs has a substantial influence on the fate of government bills. Using original data on the deliberations of 1,120 government bills submitted to the Japanese Diet from 2004 to 2017 and employing a differences-in-differences design, this study shows that committees chaired by a coalition partner or an opposition party tend to deter governments from submitting bills that will be amended, abandoned, or rejected by those committees. Rather than by directly rejecting, abandoning or amending bills, committee chairs influence legislative outcomes by preventing governments from sponsoring bills that can go against their preferences and interests.