This study tests how perceived fairness of two fiscal instruments, tax penalties and tax reliefs, affects individuals’ willingness to evade taxes in Poland and the Czech Republic. We distinguish fairness perceptions related to penalties and reliefs, which can be conceptually mapped onto retributive and distributive justice, respectively.

We ran a randomized between-subjects experiment with adult respondents in Poland (N = 247; 125 women) and the Czech Republic (N = 251; 129 women). Most participants in both countries were active taxpayers required to file an annual tax return in the preceding year. Participants were randomly assigned to one of five conditions: a 2×2 design manipulating instrument type (penalty vs. relief) and fairness (fair vs. unfair), plus a control group.

The results indicate cross-country heterogeneity in behavioral responses to fairness. In the Czech sample, fair reliefs reduced evasion relative to the relevant comparison conditions, whereas no comparable effect is observed in Poland. Unfair penalties produce a strong deterrent effect in the Czech Republic. In Poland, by contrast, evasion decreases similarly across penalty conditions whenever sanctions are perceived as credible, suggesting a stronger role for deterrence than fairness considerations.