Serviços distintos de auditoria e a independência do auditor

: evidência de Portugal e Espanha

Abstract

The increasing provision of non-audit services (NAS) by audit firms has raised concerns regarding the potential impairment of auditor independence. Following several international financial scandals and the 2008 financial crisis, the European Union implemented the Regulation (EU) No 537/2014, which introduced restrictions on the provision of non-audit services and imposed limits on their respective fees. The main objective of this dissertation is to analyse the impact of the implementation of the Regulation (EU) No 537/2014, assessing whether the relationship between audit fees and NAS fees suggests, or not, a compromise of auditor independence before and after the regulation came into force. The study focuses on companies listed on the PSI-20 (Portugal) and IBEX-35 (Spain) indices over the period 2012–2022. For this purpose, a linear regression model with firm and year fixed effects was developed. The results show no statistically significant relationship between audit fees and NAS fees, both in the period before and after the implementation of the Regulation (EU) No 537/2014. These findings suggest that the regulation did not have a direct impact on auditor independence. In practical terms, this study contributes to the ongoing debate on the effectiveness of European regulation in strengthening auditor independence, providing empirical evidence that may assist legislators, regulators, and policymakers in promoting financial governance and market transparency.

Date of Award	10 Dec 2025
Original language	Portuguese
Awarding Institution	Universidade Católica Portuguesa
Supervisor	Maria José Martins Lourenço da Fonseca (Supervisor) & Ricardo Ribeiro (Co-Supervisor)