We investigate the relationship between customer and supplier firms’ abnormal accruals to examine whether the supply chain is an important transmission channel of abnormal accruals. We propose “earnings management” hypothesis and “customer demand shock” hypothesis. Empirically, we examine the relation between a supplier’s estimated abnormal accruals and those of its major customers using Compustat Business Segment Files over the period 1987–2015. To further explore the demand shock channel, we directly test the impact of the bullwhip effect (BWE) on the linkage in abnormal accruals along the supply chain. Following the literature in operation management, we construct the amplification ratio, measured as the coefficient of variation of a firm’s orders divided by the coefficient of variation of the firm’s demand. We find that customer firms’ demand shocks link customer and supplier abnormal accruals as they propagate along the supply chain, via the BWE. Our evidence supports “customer demand shock” hypothesis. Consistent with the view that improving predictions on orders from their customers would mitigate this BWE, we find that a customer’s abnormal accruals have a much smaller impact on those of its suppliers whose auditors have expertise in the customer’s industries. Overall, our results suggest that the supply chain is an important transmission channel of abnormal accruals, and auditor expertise serves to reduce information opaqueness during this process. Our paper contributes to the literature examining the impact of BWEs on firms’ financial performance and the role of auditors’ expertise in reducing information opaqueness in supply chain.
