Public sector audit in uncertain times

In the future, environmental disasters and resource constraints will continue to impact the public sector audit environment. Governments will be held responsible for their responses and the corresponding financial impacts, particularly rising levels of public debt. Supreme Audit Institutions (SAIs) are vital in keeping governments accountable. Yet,theyalsoneedlegitimacyandtheyaresubjecttoisomor-phic pressures to gain this. Mimetic isomorphism explains SAIs’ structures, although they remain diverse, worldwide. Our analysis of extensive data about SAIs together with sta-tistical measures about countries, an international survey and document analysis enables us to make projections about what isomorphic pressures will shape SAIs and enable them to deal with an uncertain future. Examining public debt and the United Nation’s Sustainable Development Goals as case studies, we show how isomorphism will shape SAIs’ responses to an uncertain future. This exploratory research has analysed the forces that influence the structure of SAIs to ascertain how isomorphic pressures will force SAIs to deal with an uncertain future. We took economic and environmental resource scarcity as strong global trends to provide foresight about possible future(s) in public sector auditing using isomorphism as a theoretical underpinning. SAIs hold a unique role within each country. Best practice suggests that they should be independent of government, report to parliament and remain apolitical. They are also expected to be leaders within the public sector. Yet they work within national settings, beset by resource constraints, and in an environment that is increasingly global and thus are subject to global forces for change. The environment is uncertain, and more so since the onset of the Covid-19 pandemic.

Although the future is unknown, certain structures and strategies enable institutions to respond more favourably than they otherwise would. Foresight, based on current trends, can elucidate general directions for the future. These projections prepare institutions to meet future needs and opportunities (Cuhls, 2003). Public sector organisations are diverse in structure worldwide, and this is particularly the case with their auditors, Supreme Audit Institutions (SAIs).
Prior research has questioned whether diversity in SAI structure impacts government effectiveness and productivity (Blume & Voigt, 2011). In this paper, we analyse the forces that influence the structure of SAIs; this aids understanding of how these structures can develop in order to assist SAIs to deal with an uncertain future. To make these projections, we analyse the trends that influence the structure of SAIs using a framework of institutional theory. We apply our models to an extensive set of data.
Audits exist whether or not they are mandatory, as a result of a set of similar influences such as agency costs, governance and confirmation of earlier unaudited information . This finding suggests that isomorphic forces have driven the growth of audit globally. Nevertheless, how public audit is structured and the variety of ways in which SAIs deliver value varies considerably , 2020. Frumkin and Galaskiewicz (2004) argue that public sector entities yield to isomorphism due to a need for legitimacy. SAIs are unique institutions within countries, but are typically independent entities that are responsible for public audit in their own jurisdiction. Is there a common structure that SAIs trend towards? If diversity remains, how might isomorphism shape SAIs' responses to an uncertain future? Understanding the role of isomorphic forces in the nature of SAIs should assist in dealing with uncertain future trends. Isomorphic forces are the influences that cause change, and that are causing SAIs to converge on a standard model (or a small set of models). Although convergence to one or several structures may bring legitimacy, isomorphic forces identified in this study are not necessarily either an advantage or a disadvantage for SAIs. Understanding their convergence as a result of changing professional and political policies is relevant to understanding SAIs' future policies and resources.
Analysis of SAI structures is in a nascent stage, therefore this exploratory research contributes to the literature in three different ways. First, the analysis of current structures creates a 'baseline' to inform understanding of both diversity and possible reasons for it and its impacts. Secondly and importantly, we highlight global structures and examples that enable SAIs to deal with an uncertain future; and thirdly, from our elucidation of structures that aid understanding of SAI change, we suggest fruitful areas for future research within this under-researched area.
The next section of this paper presents institutional theory as our theoretical framework. This framework, applied to our data, enables us to analyse recent trends in SAIs within an increasingly uncertain environment, in order to ascertain how isomorphic pressures will force SAIs to deal with this uncertain future structurally and operationally. The following section outlines our data analysis, international survey, document analysis and two case studies -public debt and the United Nation's (UN's) Sustainable Development Goal (SDGs) -where isomorphic pressures could force SAIs to deal with an uncertain future. Our findings suggest that mimetic isomorphism has been responsible for structural changes in SAIs. Further, despite structural diversity, through the cases of public debt and the UN's SDGs we show how the International Organization of SAIs (INTOSAI) applies normative isomorphic pressure to improve SAIs' operational responses to uncertain times. We also reflect on the likelihood of these pressures to force SAIs to deal with an uncertain future. Our discussion and conclusion also outline limitations and areas for future research.

THEORETICAL FRAMEWORK
It is often stated that auditing studies are bereft of theory Jacobs & Evans, 2012). Consequently, we seek to find explanations for the identified trends to develop foresight about possible future(s) in public sector auditing. Such an approach assumes a theoretical framework that can explain change. Neo-institutional theory (often just called institutional theory) derives from organisational theory and seeks to explain similarities and differences among organizations, their practices and isomorphic changes to those (DiMaggio & Powell, 1983).
Institutional theory has been used to examine a wide range of business issues, including the adoption of International Accounting Standards by different countries (Judge et al., 2010). Laws/regulations, informal norms and conventions (institutions) influence actions of individuals and organizations. Hence, DiMaggio and Powell (1983) argue that these institutions include three forces that make organizations similar to each other, namely: "1) coercive isomorphism that stems from political influences and the problem of legitimacy; 2) mimetic isomorphism resulting from standard responses to uncertainty; and 3) normative isomorphism associated with professionalization" (DiMaggio & Powell, 1983).
Although initially public sector organisations can be culturally and contextually dissimilar and they may seek innovations which differentiate them, at a later stage, they can be influenced by a drive towards legitimacy, with the three forces of isomorphism making them more similar to each other. Frumkin and Galaskiewicz (2004) suggest that public sector entities are more susceptible to such institutional pressures than for-profit or not-for-profit entities. Because they are public sector entities (and due to mimetic pressures as described below), greater isomorphism might apply to public audit/SAIs than occurs in the private sector.
The World Bank suggests that there are almost 200 SAIs with similar structures, and they tend to follow one of three models (although, despite these similarities, we show below that they also have many diverse features). The World Bank models are the: • Westminster model, emanating from the United Kingdom and comprising an independent statutory body with 'a Comptroller and Auditor General who is an officer of the House of Commons' (Pollitt & Summa, 1997, p. 315 (Morin, 2011).
Some SAIs use another institutional model which can also include being part of the Ministry of Finance. This model is now not widely used but nevertheless applies in some countries, for example in Vietnam (Cordery & Hay, 2020). 1 Pollitt and Summa (1997) note a variant on this model in the Swedish and Finnish SAIs which were at that time part of government, as they were within their respective Ministries of Finance, but operated with independence.
In addition to structural legitimacy from using a particular model, possible parliamentary criticism means that SAIs are likely to follow recommended practice to maintain legitimacy (James & John, 2007;Keerasuntonpong & Cordery, 2018), whether that be the result of coercive, mimetic or normative forces. DiMaggio and Powell (1983) predict that coercive isomorphism will encourage organizations towards greater similarity where there is greater dependence on another organization, or greater centralization of resource supply. Frumkin and Galaskiewicz (2004) found that public sector entities were more likely to morph towards an 'average' due to coercion, and that formalisation of processes would also lead to greater adoption of 'generic' bureaucratic forms. When considering SAIs specifically, levels of government debt and international aid are examples that may have an impact, due to a nation's financial dependence and the power of the lenders/aid providers.
Organizations (such as SAIs) will be more likely to model themselves on other organizations because of mimetic isomorphism when there is more uncertainty in the relationship between means and ends, and when the goals of an organization are uncertain (DiMaggio & Powell, 1983). When there is greater participation of its managers in trade or professional organizations, organizations (such as SAIs) could become more like other organizations in the same field because of normative isomorphism.
Applying the broad outline of DiMaggio and Powell's (1983) model to SAIs, we might expect SAIs to be structured similarly when the forces of isomorphism apply. We suggest that institutional theory should be considered relevant in these circumstances: -if it is the case that SAIs audit a government that is dependent on external organizations for funding (coercive isomorphism); -when there is uncertainty about how to achieve the objectives of auditing; when goals are uncertain (mimetic isomorphism); -when there are few visible alternative models (mimetic isomorphism); and -when managers are professional and engage with professional organizations (normative isomorphism).
SAIs are likely to experience these circumstances, but to varying degrees; hence, the institutional framework in this paper assists us in explaining SAI structures and how isomorphic pressures can shape SAIs and enable them to deal with an uncertain future. Other literature has used neo-institutional theory in analysing SAIs and the environment in which they work, as we now describe.
Measures of coercive isomorphic influences can include the extent of government debt (Lamoreaux et al., 2015), and foreign aid (Judge et al., 2010;Khan & Hoque, 2016). For example Khan and Hoque (2016) find that the Bangladesh Parliament's public accounts committee was coerced by international donor agencies, a factor that might also affect SAIs. Coercive isomorphism was found in Reichborn-Kjennerud et al.'s (2019) analysis of SAIs anti-corruption work in seven diverse countries in Europe and Africa, due to country-level political systems which can lead to sanctions against a SAI when it fights corruption. Carpenter and Feroz (2001) argued that resource dependency and the need to raise funds from the capital markets meant that certain U.S. States early-adopted Generally Accepted Accounting Principles in order to raise funds from the capital market (i.e. coercive isomorphism, as sanctions would have included that these financially stressed States would not be able to raise funds). In local government, where there is more independence in the United Kingdom, fragmentation of practice is being seen to occur more readily, largely driven by different regulatory spaces (Ferry & Ahrens, 2020).
Further, Reichborn-Kjennerud et al. (2019, p. 4) found mimetic pressures as SAIs follow models from other countries, but the authors are concerned that models that 'make sense in one context are transferred uncritically to another' , for example from a country with low levels of corruption to one with high levels. Khan and Hoque (2016) also found mimetic isomorphism where Bangladesh copied the model of Parliaments such as those of Australia, Canada and the United Kingdom. Additionally, Christensen (2003) argues that mimetic isomorphism assisted the adoption of commercial accounting in the Australian public sector, due to the use of consultants who were familiar with private sector models. Although the influence of professional consultants could also be a source of normative isomorphism, Christensen (2003) argues that countries' uptake of private sector models was due to goal ambiguity, lack of technological understanding and an uncertain environment, all contexts for mimetic pressures. Similarly, Johnsen et al.'s (2001) study compares public institutions in Finland and Norway, arguing that differences in these countries' use of value for money auditing reflect a management consultancy style, and mimetic isomorphism due to the uncertain and ambiguous environment in which the local governments they studied operate. Finally, Chan et al. (2016) find mimetic isomorphism in the structure of the SAIs in Samoa and Tonga, as accountability is influenced by New Public Management (NPM) (introduced by its dependence on foreign aid) and their history, especially Samoa which was colonised by the British and has adopted the Westminster model (Heald, 2018).
In respect of normative isomorphism, Reichborn-Kjennerud et al. (2019, p. 3) observe normative pressures from professional accountants, including that private sector auditors 'define themselves away' from responsibilities involving corruption. In addition, Khan and Hoque (2016) also argue that normative isomorphism caused change in Bangladesh's government through staff taking an international training programme in Australia. Keerasuntonpong and Cordery (2018) in a study of SAIs' influence on local government reporting did not find evidence of normative isomorphism, but little other research exists on the normative impact of SAIs on their auditees.
Prior research, which has mostly been case studies, suggests isomorphism has a role in SAI change, and that succumbing to isomorphic pressures can assist SAIs to gain legitimacy. We now describe our method used to discern recent trends in both the structure and support of SAIs within this increasingly uncertain environment, in order to ascertain what isomorphic pressures will enable SAIs to deal with this uncertain future.

CONTEXT AND METHOD
Public sector audit is not demanded nor provided in a vacuum. This section briefly introduces the INTOSAI and the global environment in which public audit is projected to be undertaken in the future. Further, the specific data sources that are used in this exploratory research are also described.
INTOSAI is an umbrella membership organisation for the SAI community involved in professional standards, and knowledge and capacity building (see www.intosai.org INTOSAI and its regional organisations operate a number of committees and working groups to monitor and advance professionalism in public sector external audit. Further, it seeks to develop capacity in SAIs through, inter alia: regional forums, promoting peer reviews and cooperative audits which enable best practice to be shared, through  5 We also drew on the European Court of Auditors' (2019, p. 3) handbook which provides an overview of the 'mandate, status, organization, work and output of the 29 SAIs of the EU and its Member States and illustrate(s) the differences and similarities between them' . These sets of data formed the basis of the tables and our subsequent analysis.
Public sector audit is demanded for accountability of government and foresight suggests that these demands will grow. Specifically, resources are scarce in the public sector, as citizens demand more services, better infrastructure and joined-up responses to crises (such as the Covid-19 pandemic). Citizens also contribute towards governments' limited revenues. To meet citizens' needs, governments frequently resort to debt instruments, with public debt rising globally. 6 In respect of economic trends, the European Commission (2012) and the Mowat Centre (2014) highlight resource scarcity as an important trend facing future governments. 7 Certain geographic areas may be more resilient, with the National Intelligence Council (2012) noting the economic growth of Asia and its relative resilience to human-made crises, such as the Global Financial Crisis (GFC) (although Asia had its own crises in 1997). Outside Asia, the European Commission (2012) recounts how governments were called upon to support 'institutions too big to fail' following the GFC and how that human-made disaster, along with ageing populations, has impacted public debt, a constraint also noted by the Mowat Centre (2014). The Covid-19 pandemic has also been predicted as likely to result in a recession 8 and increased public debt, making financial resource constraints a major feature in the public sector's future, despite governments' desires to increase economic growth rates, post pandemic. Citizens require accountability with respect to any government support provided to private sector organisations, as well as any increased public debt.
Resource scarcity of a different kind increases the relevance of reporting on sustainability and related issues.
Because economic growth encourages resource consumption, and many natural resources are geographically confined, environmental resource scarcity is likely to increase (European Commission, 2012). The National Intelligence Council's (2012, p. ii) 'Global Trends 2030' report agrees that not only will resource demands escalate, but that supply and demand for food, water and energy are interlinked, so that 'tackling problems with one commodity will be linked to supply and demand for others' . The calls to limit the rates of climate change and increase environmental sustainability reflect these resource demands (Mowat Centre, 2014). Governments are therefore challenged to undertake 'a paradigm shift' , 'innovation' and 'inclusive strategies' (European Commission, 2012), especially as natural disasters are expected to increase (National Intelligence Council, 2012). The UN's SDGs have been designed to bring about better management and sharing of resources globally and all UN members have promised to work towards achieving them.
There will be a need for nations to report on and audit environmental issues (Hay, 2020) and especially against the UN's SDGs, to ensure global goals are met. This need is likely to require more cooperative audits (i.e. joint, coordinated or parallel audits) (see also ISSAI 5800 Guide for Cooperative Audit Programs between SAIs; Monroe-Ellis, 2018; Siddiqui, 2019). Rajaguguk et al. (2017) note that data for achieving such goals are likely to be held by more than one ministry. They show a case study of how a consolidated audit report was prepared for a poverty reduction programme, utilising the work of 12 teams in the SAI as well as 15 provincial audit teams. Data availability was a challenge. This is similar to that experienced in India, when the SAI audited that government's readiness to fulfil its SDG commitments for all and build effective, accountable and inclusive institutions at all levels' . The role of international 'players' (like the UN) is a feature of increased globalisation, and this research primarily draws on internationally held data which help to assess how globalisation/isomorphic pressures have occurred and therefore whether these can impact future public sector audit of resource constrained governments.
Our information for this analysis was drawn secondly from publicly available sources including the World Bank (aid, GDP, national debt, market capitalization -see Table 2). Further we used composite measures as developed by researchers and as explained below. These included La Porta et al.'s (2006) legal system classification scheme (see   audit. This would also link to the argument of Carpenter and Feroz (2001) that coercive isomorphism leads States to early-adopt Generally Accepted Accounting Principles (GAAP). Hence, we used World Bank data of total stock market capitalization in each jurisdiction as a measure of the importance for financial markets to comply with global norms and therefore to incur coercive isomorphism. These are presented in Table 2.
From If coercive isomorphism is relevant, then more aid, or lower national income (GDP per head); higher debt; or greater share market capitalization will be associated with a particular model. Our results show that is not the case. We are aware that there is some anecdotal evidence that these influences are important, but nevertheless the data do not show this with Table 2 showing that coercive isomorphism does not appear to be a strong influence over the model adopted by SAIs globally. If it is, then controlling for some other factors must also be important.

Mimetic isomorphism
As noted, Heald (2018, p. 1) observes that newly established countries have tended to copy the institutional arrangements of former colonial powers in a form of mimetic isomorphism, although he criticises it as being 'without recognition of context' . Table 3 compares the SAI models and countries' legal systems as a proxy for their colonial histories, using the classification scheme from La Porta et al. (2006) that divides countries into English, French, German and Scandinavian legal systems.
From Table 3, we observe a fairly consistent pattern, because the Scandinavian countries all use a version of the Westminster system, whereas most countries using a German-based legal system use a Board/Collegial system.
Although it might be expected that countries with a French legal system would use the Court/Judicial system, there are larger numbers using the Westminster and Board/Collegial system. Most countries using an English-law-based system use a Westminster system, but there are exceptions. Hence, mimetic isomorphism forcing countries to adopt a system based on their former colonising power is not as widely supported as might be expected.
There is evidence, however, that mimetic isomorphism plays a part in the choice of SAI model. The Westminster model appears to be adopted in less-developed countries, which might be subject to greater uncertainty. The data are mixed, although some trends are clear. Countries with less political stability, fewer political rights and fewer civil liberties tend to use the Court model (Cordery & Hay, 2020). The Westminster model exists in a wide range of countries at more extreme ends of the scales of political stability, political rights and civil liberties, consistent with the less stable countries with fewer rights emulating mimetically the more stable countries with more rights (Cordery & Hay, 2020). A similar pattern applies with property rights and securities law enforcement. As noted, colonial history indicated by the legal system (as shown in Table 2) is not as strongly associated with mimetic isomorphism. Further, even when there is a shared history, operational processes can be markedly different (as shown by Ferry & Ahrens [2020] in their study of local government audit).

Normative isomorphism
Normative isomorphism occurs when professionals engage in the activities of professional organizations or, as found by Khan and Hoque (2016), through training in other countries. Data for measures of the professionalization of accounting in a country and its public sector can be drawn from similarities in auditing and use of international standards, especially accrual accounting. Brown et al. (2014) analyse differences between countries in relation to the auditing of financial statements and the enforcement of compliance with each country's accounting standards. They measure (i) auditing: 'the quality of the public company auditors' working environment' and (ii) enforcement: 'the degree of accounting enforcement activity by independent enforcement bodies' for 51 countries (Brown et al., 2014). 9 Use of accrual accounting, whether through IFRS or IPSAS, is also a way to measure normative isomorphism, when it is taken as a measure of the professionalization of accounting in a country, rather than, as Christensen (2003)  private sector accounting profession, which is likely to be a normative influence on public sector accounting. Although these measures align with private sector auditing, they provide a reliable measure of the quality and professionalism of a country's audit profession in general; however, in countries which operate a Court of Audit and where the legal rather than the accounting profession is dominant in the SAI, this may not be the case, despite the uptake of INTO-SAI's ISSAIs or their equivalent for public audit. 10 Nevertheless, Table 4 provides a measure of potential normative influences from professional auditors. Another measure of the effectiveness of a SAI is financial accountability within a country. The IFAC public sector financial accountability index is a measure of this, and this measure is reported in Table 5.
The results in Table 5 show no differences among the various SAI models, with each model about equally likely to use cash accrual or cash transitioning to accrual. However, the data include few observations of court model countries.
As a further influence, a SAI seeking guidance on an uncertain future may approach peers in regional INTOSAI bodies (see Table 6). SAIs in a region cooperate, holding conferences and providing opportunities for SAIs to share ideas. Table 6 illustrates the extent to which normative isomorphism takes the form of SAIs converging on the model used by other members of the same regional SAI. Of the SAIs for which data are available, the Westminster model is most common in almost all regions, the only exception being ASOSAI (Asia) which has more entities using the Board/Collegial model. There is evidence that some regions are converging on one model, for example the Westminster model is extensively used in the OLACEFS (Latin American) region. In this case, the jurisdictions for which data are not available are a substantial limitation, especially in the CREFIAF (Francophone African) and CAROSAI (Caribbean) regional groups.
The notes below the table provide the full name of each regional organization and its relevant website.
The influence of INTOSAI itself is likely to lead to an increased level of normative isomorphism, especially in SAI practice, through its Congress, Working Groups and committees as well as its standards and journal (as noted in Section 3).

SAIs' capacity to respond to future challenges
Given the observation of strong normative isomorphic forces on SAIs' structures, how does normative isomorphism assist these SAIs operationally to respond to future challenges and what does it tell us about the future of public sector audit? The intent of this research is to understand how isomorphic pressures will force SAIs to deal with an uncertain future, that is how can they achieve legitimacy in respect of global trends affecting governments in the future, with 9 The auditing index includes measures for licensing, quality assurance, audit fees and litigation risk, collected from the International Federation of Accountants. The enforcement index measures the powers and activities of the body that regulates auditors. 10 We thank one of the peer reviewers for pointing this out.
TA B L E 6 SAI models in each regional SAI  Future development will affect our delivery of these services to a great extent -speed of changes in technology, global connections and the increasing availability of data. . . [there will be] considerable changes in the natural environment and cultural diversity. . . In this more diverse, dynamic, and connected world, how the public sector tells its story and assures the public it is meeting their expectations will be fundamental to maintaining the public's trust and confidence in the public sector (R16).
Normative pressure has been applied to SAIs to force them to deal with resource scarcity, particularly public debt.
Since 1989  Highlighting the growing issue of public debt recognises that 'this is an intergenerational equity issue' (INTOSAI, 2007). The focus has been on assisting SAIs to develop the professional capacities to monitor, review and audit public debt management, and to shape the social and economic environment for future generations. For example the Mexico Accord recommendations encourage, inter alia, a proactive and holistic approach, urging SAIs without the mandate to audit state debt to request a law change so that they can do so (INTO-SAI, 2007). Further, the Beijing Accord recommends that INTOSAI should 'use its influence to continue to promote the development of harmonized financial reporting frameworks within the public sector to provide greater transparency in respect of government operations, particularly in relation to government debt' (INTOSAI, 2013). It also recommends, inter alia, better public finance performance audits, strong financial statement audits and evaluation of public financial policies (INTOSAI, 2013). External organizations, for example the UN, also recognise the key role of SAIs with the UN Resolution A/66/209 (INTOSAI, 2013). In addition to Committees and Task Forces on public debt, 11 INTOSAI developed ISSAIs (5410-5450) to assist audit practice and consistently state that experienced and well-trained auditors should be involved in public debt audits (INTOSAI, 2007(INTOSAI, , 2013. The need for SAIs to be independent and to draw on regional and international networks (i.e. INTOSAI and its regional organisations) underpins the advice provided to SAIs (INTOSAI, 2013), as well as the work of the KSC and IDI. 12 This was commented on by one of our survey respondents: [SAIs in developing countries] face unique challenges due to their geographical location and size. [INTO-SAI's} Regional organisations . . . and development partners such as . . . IDI have greatly contributed to the development of these SAIs and should continue with the good work (R23).
Our survey respondents not only pointed to the need for SAIs to draw on best practice, but also argued that this would have a future impact on the type of audits provided. For example respondents stated: Future development in auditing and public sector management will give a greater effect on Performance Audit as citizens demand that resources are used efficiently, effectively and economically for a developing country. . . better oversight and transparency related to Good Governance. . . can also lead to a better international rating (R26).
[Recent reforms] provide a method to help [our country] to achieve fiscal responsibility and access to the capital markets. . . to be more efficient with the resources and cautious with its expenditures. . . This may also make us shift from mostly compliance audits to make more performance audits (R22).
Hence, INTOSAI has developed policies and processes which will provide normative isomorphic pressure to help SAIs (no matter their structural type) to develop the expertise needed to assist governments to manage intergenerational equity . The future of audit is likely to include more performance auditing covering a broader remit to ensure that debt and financial resource scarcity is kept in check.

Resource scarcity and the SDGs
Normative pressure has also forced SAIs to deal with environmental resource scarcity, with the SDGs being an emerging area. All UN members adopted the 2030 Agenda for Sustainable Development in 2015 with the aim to ensure economic, social and environmental sustainability (United Nations General Assembly, 2015). The Millennium Development Goals (MDGs) were a forerunner of this response to unequal sharing of resources. As SDGs are a national commitment, this suggests auditors will need to monitor and to report on each nation's progress towards achieving their SDGs. regional working groups assisted SAIs and pushed SAIs to ensure they also had practices that are consistent with environmental protection (INTOSAI, 2010;Monroe-Ellis, 2018 13 The other two were 'to endorse the INTOSAI's 2017-22 strategic plan to increase the contribution SAIs make to improving accountability and transparency in public management around the globe. . . and adoption of the new framework for professional pronouncements' (INTOSAI, 2015).
14 More than 70 have been completed (Guillán Montero & Le Blanc, 2019). 15 Guillán Montero and Le Blanc (2019) note that over 70 SAIs are participating across all six INTOSAI regional groups (in four languages), that SAIs from the Arabic speaking region are joining from 2019 and that in some regions, auditing of preparedness is a regional effort.

DISCUSSION AND CONCLUSION: THE FUTURE OF PUBLIC AUDIT
This exploratory research has analysed the forces that influence the structure of SAIs to ascertain how isomorphic pressures will force SAIs to deal with an uncertain future. We took economic and environmental resource scarcity as strong global trends to provide foresight about possible future(s) in public sector auditing using isomorphism as a theoretical underpinning. SAIs hold a unique role within each country. Best practice suggests that they should be independent of government, report to parliament and remain apolitical. They are also expected to be leaders within the public sector. Yet they work within national settings, beset by resource constraints, and in an environment that is increasingly global and thus are subject to global forces for change. The environment is uncertain, and more so since the onset of the Covid-19 pandemic.
Institutional theory has been used to examine change within and across organisations in respect of a wide range of issues (e.g. DiMaggio & Powell, 1983;Judge et al., 2010). In this paper, we have focused on forces that may bring about structural change in SAIs, suggesting that these forces will also support SAIs to deal with an uncertain future.
The data show that although SAIs have similarities, and there is some evidence of isomorphism (SAIs moving towards a standard model), the extent of similarity should not be overstated. Each country is likely to have some unique features. It is also very clear that there is as yet no single standard model. Neo-institutional theory and isomorphism appear to have limitations in their application to the field of SAIs, based on the available evidence. Nevertheless, similar isomorphic forces could be encouraging SAIs to converge on one of the three major models that exist around the world, with the Westminster model appearing to be becoming the standard model.
There are limitations to our analysis, and these suggest areas for future research. The limitations of our study include that we only examine the SAIs at a point in time -we do not examine case studies of change in any countries.
We use the legal system as a proxy for colonial history, without examining national histories more closely. The issue of whether the influence on the SAI derives from colonial history or legal system is a complex one. The legal system is a more likely source, but there exist papers such as Heald (2018) that attribute auditing arrangements to colonial history. The topic is further complicated by the fact that some countries at different times were part of one empire and then another, and also the existence of an 'informal empire' (Darwin, 2013;Henderson, 2015) where Britain exercised substantial influence over some countries without them being formally brought into the empire. Other colonial powers probably had similar influences. These issues imply that there is potential for research to examine when it was that changes occurred in SAI models, and what were the factors driving those changes.
Reviewing the influences towards isomorphism shows that there are some effects, but not from all of the isomorphic forces. We do not find evidence of coercive isomorphism having an effect through aid, debt or stock markets.
There is some evidence of mimetic isomorphism because countries which lack stability or rule of law are more likely to emulate stable countries and adopt the Westminster model. There is consistent evidence that normative isomorphism has an effect on accounting and auditing requirements, a strong profession leading towards adoption of accrual IPSAS and membership of regional SAI groups having an impact. If coercive mechanisms do not seem to have driven structural isomorphism but mimetic and normative pressures have, what does this mean for the future, for SAIs seeking legitimacy and shaping their responses to an uncertain future?
SAIs, working within the public sector, are likely to be driven towards legitimacy (Frumkin & Galaskiewicz, 2004), and although this may mean there are internal (national) forces that drive their legitimacy, as unique institutions, we have considered global (external) forces that could shape change within individual SAIs. Country indicators help us understand whether coercive isomorphism could occur when SAIs audit a government that is dependent on external organizations for funding such as aid or having lower GDP; higher debt; or greater sharemarket capitalization.
We found no correlation between these factors and a particular model. However, this could change, and increased resource scarcity might be sufficient to increase the pressure for coercive isomorphism by external agencies such as lenders or aid agencies, or other countries that provide political support 16 (Lamoreaux et al., 2015). Changes that might lead to increases in the forces towards coercive isomorphism are an example of possible changes to SAIs in the future.
We also considered whether mimetic isomorphism arises due to inherent uncertainty about how to achieve the objectives of auditing, when goals are uncertain or when there are few visible alternative models. We found evidence that mimetic isomorphism plays a part in the SAI model in use by countries, with the Westminster model adopted in less-developed countries, which might be subject to greater uncertainty and which also might be relatively small.
However, colonial history appears not to be a very strong mimetic isomorphic pressure and this is an area where more evidence (e.g. regional case studies) could elucidate why prior understandings of colonialism are not shown to be a mimetic force. Resource scarcity issues could well increase the uncertainty faced by SAIs and thus their mimetic need for isomorphism with respect to their structures.
In respect of potential normative influences, there is some evidence that countries with a strong accounting and auditing profession are more likely to apply the Westminster system. There was little evidence of particular pressures coming from the IFAC public sector financial accountability index. However, we did find regional similarities that would suggest the INTOSAI regions work to assist SAIs in choosing structural change. Nevertheless, there are many national differences in SAI structures. One of the influences towards normative isomorphism was the strength of private sector accounting and auditing in a country, although we were unable to link relative strengths of the accounting versus legal profession in ascertaining whether this would result in a Westminster or Court of Audit structure. Nevertheless, where normative isomorphism drives private sector audit, we suggest that resource uncertainty issues will lead to increased private sector influence over public sector accounting and auditing as a practice.
We find that global pressures, both mimetic and normative, force SAIs to deal with an uncertain future. Operationally, INTOSAI has become a key professional body applying normative isomorphism to improve SAIs' capabilities and to strengthen their ability to remain independent, through international and regional support. This occurs despite structural diversity. We examined two resource constraint issues, namely, public debt and the UN's SDGs, as case studies to show how this isomorphism can improve SAIs' operational responses to an uncertain future. Here, we found that the work of INTOSAI, through its Congress, working groups, standard setting and IDI initiative, as well as working in consort with the UN, has enabled SAIs to engage in such audits as the preparedness of governments for implementing the SDGs, to help governments work towards SDG implementation and discharge accountability for their commitments. Within this community, members encourage SAIs to respond to future challenges, such as Pamela Monroe-Ellis' (2018) challenge to work towards meeting SDG15. In addition, SAIs look to the INTOSAI regional organisations for advice from members on performance audits and evaluations, recognising that their unique context may require adaptation. SAIs will actively develop more performance auditing not only to deal with the SDGs but also debt as managing increased indebtedness requires governments to operate effectively and efficiently. The current pandemic has seen huge increases in government spending and debt, and the influences of both the pandemic itself and the increased debt can be expected to increase the mimetic pressure for SAIs to adopt practices used in other countries.
We expect that current pressures will lead to future changes that increase the extent of isomorphism among SAIs.
We are able to use our data to make some specific predictions, although we acknowledge that further research is needed.
Specifically, we predict that there will be greater trends towards the three forces of isomorphism, especially the two forces that are currently influential, mimetic and normative isomorphism. That is SAIs will continue to model themselves on each other, especially when their environment is uncertain (mimetic isomorphism), and to adopt techniques learnt from professional auditors through interaction with organisations such as INTOSAI (normative isomorphism).
Although we did not find evidence of coercive isomorphism, it is still a plausible force, so that it is likely there will be evidence of SAIs being influenced to copy each other to meet the demands of lenders or aid providers. As a result, SAIs 16 Lamoreaux et al. (2015) shows that World Bank appears to overlook some accounting and auditing requirements for countries whose geo-political interests are aligned with those of the United States.
that face more uncertainty, interact more with professional bodies and have more demand from outside bodies will tend to become more similar to leading SAIs. There is likely to be a continuing trend to adopt the Westminster model, but that will be conditional on whether the normative professional influences that an SAI is subject to arise from bodies using this model. While we accessed SAIs' self-reported data from INTOSAI and a range of publicly available data, as well as responses to our survey of INTOSAI members, we acknowledge that the data are incomplete and have been collected at different points in time, although it is the most current at the time of writing. As an exploratory study, we argue that there is a need to develop better databases for more in-depth research that could enhance our initial findings. This is particularly necessary in regions which we know little about, for example the OLACEFS (Latin American), CREFIAF (Francophone African) and CAROSAI (Caribbean) regional groups.
The data we have been able to access have shown that although structurally mimetic forces drive a move towards the Westminster model, especially in emerging economies, there is wide variety in SAI structures. These will reflect the specific legal and financial situations of each nation. Hence, although the World Bank 'three SAI model' is a convenient categorisation, much more variety exists. INTOSAI, as a strong professional body, enables SAIs to navigate these differences and to assist governments and citizens in reporting and managing resource constraints, particularly in public debt and environmental concerns and thus is a normative pressure forcing SAIs to deal with an uncertain future. As INTOSAI is a body controlled by its members, SAIs also contribute to the forces driving their own change.