**1. Introduction**

The rising level of anti-corruption disclosure has attracted significant attention from state leaders, policymakers, academics, and company stakeholders [1–3]. Corruption may be defined in the simplest terms as the illicit pursuit of personal gain [4], while Transparency International [5] defines corruption as "the misuse of authority for private benefit". Corruption is a global ethical problem with social and economic repercussions, including increasing corporate costs; undermining progress; negatively impacting the quality of life, education, and health systems; as well as increasing poverty and unemployment rates [3,4]. The cost of corruption to governmental organizations, businesses, and individuals is well documented in the literature [6,7]. In the last two decades, bankruptcy and financial scandals involving a variety of organizations have highlighted the prevalence of corruption and its impact [2]. The World Bank (2018) estimates that the various forms of corruption, including bribery, fraud, conflicts of interest, and the falsification of financial statements, cost over US\$ 1 trillion annually. It has been argued that the disclosure of corporate anti-corruption efforts is a useful tool in the battle against corruption [3,8,9].

Whilst it may be possible for individuals or companies in all industrial sectors to find opportunities for corrupt practices, in 2019, the IMF [10] singled out extractive industries as a possible corruption hotspot. Ref. [11] suggested that anti-corruption disclosure (ACD) would be more beneficial for this sector due to its businesses being characterized by high rent-seeking, high investment, and high-risk character. Ref. [12] studied the literature on extractive sector reporting and found a lack of research on the sector's disclosure, providing further motivation for investigating this significant sector.

**Citation:** Ghazwani, M.; Whittington, M.; Helfaya, A. Assessing the Anti-Corruption Disclosure Practices in the UK FTSE 100 Extractive Firms. *Sustainability* **2023**, *15*, 5155. https://doi.org/10.3390/su15065155

Academic Editor: Roberta Costa

Received: 1 February 2023 Revised: 7 March 2023 Accepted: 9 March 2023 Published: 14 March 2023

**Copyright:** © 2023 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).

Corporate reporting is questioned from a number of perspectives. Financial content has the longest reporting history and the greatest level of oversight and control from authorities. Still, failures of large companies on major stock markets, for example, Enron, Lehman Brothers, and WorldCom show that even the decision-making usefulness of financial reporting could not be relied upon. Recommendations from academics [13] and from professional standard setters such as [14,15] pointed to expanding the scope of what should be reported. This should include not just quantitative financial indicators that are clarified by narrative information but also value-creating factors that are not clearly reflected in financial statements [16,17]. Thus, annual reports should now contain narrative information about a range of factors, including a company's efforts to combat corruption [18,19]. The breadth and depth of information to disclose is a continuing debate. The need for "value relevance," often limited to the shareholder's perspective on value, could be a guiding principle for the decision to disclose non-financial content. However, research has found it difficult to find a clear link between such disclosure and share value [20]. From a broader economic perspective, non-financial disclosures have been found to have little effect on the economy [21,22].

In corporate reporting, anti-corruption disclosures are generally included within the broad category of non-financial disclosures as part of social disclosure, including employee information (gender pay gap, for example), social engagement, and modern slavery reporting. Such corporate ACD purports to inform investors and other stakeholders of a company's commitment to eliminating corruption and promoting transparency and accountability [9]. Conceptual and empirical research has examined corruption from a number of angles—for example, as a concept [23], its origins and consequences [24], its assessment [25], and how to prevent it [26]. Such research can be complicated by differing definitions of corporate corruption and differing requirements across national jurisdictions [9]. Despite these divergent stances, attempts to reduce corruption are generally increasing worldwide (see, for example, [4]).

Such complexity leads us to adopt a case study approach that should have value for wider jurisdictions [27]. This study seeks to investigate ACD within the extractives industry, including oil and gas extraction, focusing on large UK-listed companies. The introduction of the UK Bribery Act (2010) [28] provides an additional focus alongside broader international pressures on ACD from various transnational bodies. To investigate the story of ACD within the UK-listed extractive industry, we will employ metrics that have previously been applied to other areas of non-financial reporting, primarily environmental reporting, which is often significantly more voluminous.

Prior CSR literature has focused on environmental reporting where there is a developing history of significant disclosure running into potentially many pages in an annual report (see, for example, [18,29–32]). This study seeks to apply these measures to ACD, where quantity is much reduced, but it is still important to understand trends, diversity, and depth of corporations. Previous studies show that the choice of metric can lead to differing conclusions on the relative quality of corporate disclosure [30,31,33]. Hence, the FTSE100 extractive companies' anti-corruption disclosures are compared using six measures/indices of reporting quality from the previous environmental accounting research above. The present research divides these measures into two categories (unidimensional measures and compound/multidimensional measures) based on their complexity and dimensionality. There are two "quantity measurements" and one "scope measurement" that are used to measure the information quality in terms of size and coverage of relevant topics, and four compound metrics. The compound metrics have been taken from the literature: the [34] disclosure scoring method (ACHI); [32] quality index of environmental disclosure (SHI); and [35] total quality index (TQLI) [35].

Using a quantitative approach, this study shows that both the design of the quality measurement and the coverage of multiple quality characteristics substantially influence the quality scores and rankings of the sampled extractive firms. It is clear from this data that the quality measures' design impacts the reporting quality ratings [30,35,36]. There are several consequences for a wide range of stakeholders. For both readers and assessors of corporate anti-corruption performance reports, reporting quality is a multifaceted concept covering many features, such as content, credibility, assurance services, and readable content using visual tools. Additionally, the ACD must be credible in order to be accepted by policymakers and standard-setting organizations such as the United Kingdom Bribery Act 2010 and third-party assurance (see, [30,31,37,38]). Anti-corruption reporters and their readers have a trust gap in practice. Thus, a consistent set of ACD guidelines and assurance standards must be established by policymakers, standard setters, and anti-corruption authorities to narrow this gap. Accordingly, the current research aims to answer the following two questions.

**RQ1**. *Can the deployment of reporting quality measures developed in the environmental reporting field enhance our understanding and interpretation of corruption-reporting quality and behavior?*

**RQ2**. *Does the use of these metrics provide consistent evidence that corporate ACD has responded to the introduction of the UK Bribery Act?*

This research is structured as follows. Section 2 presents the literature review, and then Section 3 explains the research methodology. The research findings are discussed in Section 4. Section 5 concludes the study.
