Objectives <p>Perceived police corruption is known to influence public support for vigilantism. The implication is that controlling corruption can minimize support for it. However, until now, the answer to the following question remains unresolved: Does police anti-corruption signaling affect public support for vigilantism?</p> Methods <p>We employed experimental vignettes in which university students in Pakistan were randomly assigned to one of two groups: an experimental group and a control group. Participants in the experimental group read a hypothetical police anti-corruption news report, while the control group did not. The vignettes were embedded in a questionnaire completed by 206 participants in an online survey.</p> Results <p>The results demonstrate mixed effects of the anti-corruption reform signal on vigilantism. While the signal increased willingness to intervene to stop vigilantism, it neither affected support for vigilantism nor willingness to supply information to the police to hold vigilantes accountable.</p> Conclusions <p>The results imply that promoting police integrity can encourage citizens to intervene to stop vigilantism.</p>