Political bias has been identified as a driver of leniency towards corrupt politicians. Yet, evidence suggests that a number of contextual factors can moderate its influence on corruption assessments. The interplay between individual variables, particularly individual moral standards, and political bias over corruption evaluations, however, is yet to be addressed. We explore this using two measures that operationalize bias and moral standards in political settings: partisan moral reasoning (PMR), measuring leniency towards in-party (vs. out-party) transgressions, and tight moral reasoning (TMR), a measure of broader rejection of political transgressions regardless of the perpetrator’s affiliation. Contrary to our expectations that high PMR and low TMR would jointly drive favourable attitudes towards politicians accused of corruption, we found that low and high TMR respondents only diverge at low levels of PMR. Results suggest that the counterbalancing effect of morality on tolerance towards corruption is outweighed by the overpowering influence of political bias.