Sustaining your stance by speaking your mind: Expressing moral judgments increases certainty and prevents moral desensitization

When news about another person's wrongdoing goes viral, people will hear about it repeatedly through social and traditional media outlets. Prior research suggests that this repeated exposure reduces how unethical people think the wrongdoing is – a moral repetition effect . The present research reveals that repetition no longer reduces moral condemnation when people express moral judgments upon each exposure, as they often do in the real world by commenting on news about wrongdoing. Drawing on attitudes research, we argue that repeatedly expressing moral judgments eliminates the moral repetition effect by increasing how certain people feel about their judgments. We found support in a meta-analysis ( k = 13 experiments, N = 6548 participants) and three pre-registered experiments ( N = 2637). The meta-analysis finds a smaller moral repetition effect for wrongdoings that tend to make people feel more (vs. less) certain about their moral judgments. Experiment 1 finds that people hold their moral judgments about a repeatedly encountered wrongdoing with more certainty when they actively express these judgments on each encounter. Experiments 2 and 3 show that prompting people to repeatedly express their moral judgments eliminates the moral repetition effect. These findings deepen our understanding of how and when repetition erodes moral condemnation and offer an actionable strategy to counteract repetition's effects. Encouraging people to express their views – rather than just to passively consume information – may help prevent moral desensitization to wrongdoing.