In a new paper published in the journal Deviant Behavior, the authors tested an intervention that aims to address the issue of deviant behaviours – such as digital piracy, tax cheating or excessive drinking – being underreported in surveys.

The researchers applied the theory of moral licensing, which suggests that when people behave virtuously, they later indulge in behaviour that might otherwise threaten their moral self-image.

In the survey design, the researchers asked participants to recall virtuous actions. Across two experiments involving questions about digital piracy, the survey first asked participants about positive but common activities that support the creative industries, such as owning a streaming subscription or attending the cinema.

When later asked about digital piracy, respondents who had been primed to recall their good actions were more likely to admit to illegal downloading, the paper found.

Additionally, individuals who were particularly motivated to present themselves favourably were typically the most reluctant to admit to deviant behaviour, and these participants showed the greatest increase in honest reporting after the moral licensing prime.

Dr Kate Whitman, ethical consumption researcher at the University of Portsmouth, said: “By giving respondents an opportunity to reflect on their positive actions first, we reduced the psychological cost of admitting wrongdoing, especially for those most concerned with appearing moral.”

The study also saw a particularly strong effect among female participants, as women in the sample showed higher social desirability bias. “Women were more likely to underreport piracy, as is common for morally sensitive or unethical behaviours in survey research,” explained Whitman.

Dr Zahra Murad, associate professor in behavioural economics at the University of Portsmouth’s School of Accounting, Economics and Finance, said: “Our results show that providing participants with the opportunity to reflect on morally virtuous behaviours before answering sensitive questions significantly increases willingness to disclose deviant behaviour.

“This simple technique can strengthen the reliability of survey data and help researchers obtain more complete insights into behaviours that are otherwise hidden.”

• Whitman, K., Murad, Z., Cox, J., & Vrij, A. ( 2025 ). ‘License to Spill: The Influence of Moral Licensing Survey Primes on Deviant Behavior Reporting'. Deviant Behavior, 1–16.