In these contexts, improvements in enforced compliance may depend not only on deploying new tools to monitor taxpayers, but on expanding rules-based enforcement efforts by tax collectors.

Improving access to information has been at the heart of efforts to improve monitoring of taxpayers. These strategies have reflected the centrality of information to tax enforcement: it is through access to information on income, wealth and economic transactions that governments are able to identify evasion and avoidance, pursue enforcement, and impose penalties. Some reform efforts have focused on improving the collection, management and sharing of data that is already possessed by governments – including improved data sharing across divisions _within_ tax administrations in order to cross-reference the tax declarations of firms and individuals across tax types. Meanwhile, many countries have also sought to improve access to third-party data. This third-party data can come from a variety of sources: cross-referencing of tax declarations from firms that do business together, data from other government agencies e.g. on land, property or business registrations, or external sources like public contracts, bank accounts, stock exchanges or credit cards. Finally, tax withholding often enables a particularly effective form of data gathering for tax enforcement. In most developing countries the bulk of income taxes are already collected via withholding taxes on salaries. Some countries have correspondingly considered the potential merits of expanding withholding taxes, for the VAT and elsewhere, in order to widen the tax net.

Reforms have also sought to expand audit capacity – while reducing opportunities for taxpayers to engage in tax evasion and avoidance. Along with expanded access to information, governments and donors have invested in the expansion of audit capacity, with a particular focus on the introduction of risk-based audits. The goal has been to improve the technical capacity of audit departments – increasingly focused on challenges related to international taxation – while putting in place strategies to ensure the most efficient targeting of audit resources. Meanwhile, efforts have focused in parallel on simplifying tax rules – and eliminating loopholes – in order to reduce opportunities for evasion and avoidance. For example, governments may reduce the range of VAT rates in order to simplify enforcement,<sup>50</sup> may introduce simplified methods for property tax assessment,<sup>51</sup> or may explore simplified approaches to confronting cross-border transfer pricing.<sup>52</sup> Finally, in many cases governments have made access to certain kinds of services conditional on producing evidence of tax compliance – though enforcement of such rules often appears to have been uneven, or short-lived.<sup>53</sup> Similarly, extensive reform efforts have been focused on improving the performance of tax administrations themselves. Semi-autonomous revenue authorities have been created across much of Latin America and Anglophone Africa in particular, in order to provide improved work

> 50 Bird, R., Gendron, P. P., & Rotman, J. L. (2005). VAT revisited: A new look at the value added tax in developing and transitional countries. United States Agency for International Development.

> 51 Jibao, S., & Prichard, W. The political economy of property tax in Africa: Explaining reform outcomes in Sierra Leone. _African Affairs_ 114(456): 404-431; Fish, P. (2018). Practical guidance note: Training manual for implementing property tax reform with a points-based valuation. _African Tax Administration Paper 2._ Brighton: International Centre for Tax and Development.

> 52 Durst, M.C. (2019). _Taxing multinational business in lower-income countries: Economics, politics and social responsibility._ Brighton: International Centre for Tax and Development.

> 53 For example, <mark>a fiscal sustainability project in the West Bank in 2011 made local municipalities</mark> services, such as car registration, conditional on proof of property tax payment. Within participating municipalities collection increased to between 85 and 100 percent. World Bank. (2012). _West Bank & Gaza - WBG Support for Fiscal Sustainability And Public Financial Management_ . Washington: World Bank.

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