The Enron case and other fnancial scandals at the beginning of this century caused a great concern among regulators and policy-makers about the necessity of new regulations to prevent, or at least to make it difcult, such cases to repeat. A common feature of these scandals was that the accounting information released by the companies did not refect the current economic and fnancial situation. Thus, market participants who made investment decisions on the basis of this information were being tricked by managers, the ultimate responsible of the accounting information produced and released by the company. As posed by Aguilera & Cuervo-Cazurra (2009), loss of confdence in accounting information, caused by these corporate scandals, favoured an increasing demand for sounder corporate governance structures and practices. They argued that the reaction of regulators to these demands has been twofold. On the one hand, through the approval of “hard legislation”, such as the Sarbanes–Oxley Act (hereinafter SOX Act1 ) aiming to improve governance practices which should ultimately lead to higher accounting quality. On the other hand, and usually complementing this hard approach, the approval and endorsement of codes of good practices (hereinafter, CGP) has been a “soft legislation” reaction to the demand of better governance. These codes constitute non-binding set of principles, standards or best practices, issued by a collective body, and relating to the internal governance of corporations (Weil and Manges 2002). Both hard and soft legislation approaches emphasize the role of the audit committee in guaranteeing the quality of accounting information. DeFond & Zhang (2014, 306) argued that a major consequence of the SOX Act was to raise public awareness of the role auditing plays in efective corporate governance. The most visible sign of this upgrade in the status of the auditing profession being the mandated changes to the audit committee. These changes attempted to increase the demand for audit quality by improving client governance. A number of studies have investigated whether fnancial reporting quality has improved as a result of these requirements (e.g. Klein 2002, Abbott et al. 2004 and more recently, De Vlaminck & Sarens 2015). As for the soft legislation approach, CGP generally include a bunch of recommendations on the audit committee. As an example, the Spanish 2006 Unifed Good Governance Code of Listed Companies (hereinafter “Unifed Code”) (CNMV 2006) included eight recommendations (out of 58) specifcally referring to the audit committee, and the 2015 reform of the Unifed Code (CNMV 2015) further expands the powers of the audit committee and it also establishes new requirements.