The grey side of procurement: Measuring the prevalence of questionable purchasing practices

Buyer-supplier relationships may be exposed to ethically questionable purchasing practices. This can have major financial and reputational consequences for individuals and organisations. Various studies have assessed procurement professionals' ethical judgements regarding questionable purchasing practices and a handful have estimated the prevalence of these practices. The insights from these studies, however, cannot be straightforwardly extrapolated to today's practice. First, the studies have mostly estimated prevalence without controlling for social desirability bias. The estimation of the prevalence of questionable practices based on subjects' responses is non-trivial, as it may be prone to socially desirable response behaviour. Second, most of the studies were conducted decades ago and the role of the purchasing function has changed significantly ever since. Based on these observations, the present study makes two main contributions to the literature. First, it methodologically extends extant studies by estimating the prevalence of questionable purchasing practices in Europe while controlling for social desirability bias. Specifically, the present study applies the recently developed Extended Crosswise Model to test for socially desirable answers and presents these prevalence estimates in comparison to estimates obtained via a direct questioning technique. The findings highlight the ongoing prevalence of unethical practices in buyer-supplier relationships and the need for organisations to be vigilant in addressing them. Post-hoc analyses indicate that gender, work experience, perceived levels of public sector corruption, and governmental procurement agreements affect the involvement in questionable purchasing practices. Second, the present study examines how earlier and newly identified questionable practices are perceived in the current business environment. The results suggest that ethical perceptions have changed and that most unethical practices are observed in supplier selection. From a theoretical perspective, the present study responds to both the call to further investigate ethical issues in supply chains (Quarshie et al. 2016) and the call to address social desirability bias in purchasing and supply management research (Ried et al., 2022). From a managerial perspective, our research can serve as a starting point for organisations to develop strategies to mitigate their impact and promote ethical behaviour throughout the purchasing process.