Zhiying Hu

1 Introduction The sudden outbreak and rapid spread of COVID-19 in late 2019 created an unprecedented challenge for the audit function. As a systemic and exogenous shock, the pandemic disrupted firms' operations and constrained auditors' ability to obtain audit evidence through conventional procedures. This setting provides a unique opportunity to examine how auditors adjust their risk responses when facing widespread uncertainty and operational disruption.

1 Introduction Extensive research explores the determinants of corporate tax avoidance,1 with a particular focus on the influence of corporate governance (Kovermann and Velte 2019; Wang et al. 2020). Previous studies show that equity-based incentives (Armstrong et al. 2015; Desai and Dharmapala 2006; Gaertner 2014; Rego and Wilson 2012), ownership structure (Chen et al. 2009; Desai and Dharmapala 2009; Khan et al. 2017) and internal governance structures such as board oversight (Armstrong et al.