Across two studies, we tested whether evaluations of sexual misconduct allegations against male politicians are made in a partisan biased manner. First, we investigated the likelihood a sexual misconduct allegation made by a female staffer was perceived as legitimate by Democratic and Republican participants when the accused politician’s party affiliation was aligned (versus unaligned) with the participant’s own affiliation (Study 1). We also tested whether partisan bias was conditional on the strength of the participant’s expressive partisanship (Study 2). In Study 1, 182 Democratic and 159 Republican affiliates (N = 341), recruited via Amazon Mechanical Turk, were randomly allocated to one of three conditions (Democratic, Republican, or unaffiliated accused politician). Findings indicated that Republican participants were less likely than Democrats to perceive a sexual misconduct allegation as legitimate, irrespective of the politician’s party affiliation. Nonetheless, participants were not more likely to perceive a sexual misconduct allegation against an unaligned politician as more legitimate than against a politician of their own party. However, in a replication of Study 1 with a larger sample (301 Democratic and 301 Republican affiliates), Republicans (but not Democrats) demonstrated partisan bias in judgements of the legitimacy of misconduct allegations. Expressive partisanship did not moderate this partisan effect.