than external resource mobilisation, the more it will be able to deploy sustainable development strategies and policies that are responsive to the needs of its people and accountable to them.’161 Moreover, domestic resource mobilisation diminishes the reliance on external aid, which has been considered ‘unpredictable and unsustainable’, ‘inconsistent and insecure’.162 Based on human rights monitoring bodies’ existing work, it is clear that human rights law does not prescribe precise taxation policies; states have the discretion to formulate those most appropriate to their circumstances. It does, however, impose some limits on states’ discretion related to their taxation policies. Devoting maximum available resources A commonly held position suggests that states neglecting to undertake reasonable efforts to ensure domestic revenue generation may be failing to use their maximum available resources.163 Taxation is often presented as one of the most effective tools for generating resources for human rights realisation.164 Using maximum available resources requires widening the tax base and improving tax-collection efficiency. It has also been suggested that, when states’ taxation ratios are clearly lower than their development levels, the implication is that they are not taking steps to leverage maximum available resources.165 Low domestic taxation revenue has been considered a major obstacle to a state’s ability to meet obligations to devote ‘maximum available resources’ for the realisation of economic, social and cultural rights.166 In recent years, the CESCR has been more explicit in addressing the links between taxation and maximum available resources. It ‘urges’ states to implement tax policy that is ‘adequate’, ‘progressive’ and ‘socially equitable or fair’, to ensure sufficient resource mobilisation to implement economic, social and cultural rights.167 Reviewing Great Britain and Northern Ireland’s report, the CESCR noted concerns regarding: ‘[T]he adverse impact that recent changes to the fiscal policy in the State Party, such as the increase in the threshold for the payment of inheritance tax and the increase of the value-added tax, as well as the gradual reduction of the tax on corporate incomes, are having on the ability of the State Party to address persistent social inequality and to collect sufficient resources to achieve 161 ‘Report of the Special Rapporteur on poverty, Magdalena Sepúlveda Carmona’ (2014) UN Doc A/HRC/26/28, para 52. 162 ‘Interim report of the Special Rapporteur on health, Anand Grover’ (2012) UN Doc A/67/302. 163 See, eg, ‘Report of the Independent Expert on foreign debt, Juan Pablo Bohoslavsky’ (2016) UN Doc A/HRC/31/60, para 12, E/C.12/SLV/CO/3-5 (2014), para 8. 164 See, eg, Concluding Observations El Salvador E/C.12/SLV/CO/3-5 (2014), para 8; Concluding Observations Honduras E/C.12/HND/CO/2 (2017), para 20. 165 ‘Report of the Special Rapporteur on poverty, Magdalena Sepúlveda Carmona’ (2014) UN Doc A/HRC/26/28, paras 55–57. 166 See, eg, ‘Report of the Independent Expert on poverty, Magdalena Sepúlveda Carmona’ (2011), UN Doc A/HRC/17/34, para 49; ‘Report of the Special Rapporteur on food, Olivier De Schutter’, Mission to Guatemala (2010) A/HRC/13/33/ Add.4, para 87(e). 167 See, eg, Concluding Observations Canada E/C.12/CAN/CO/6, para 10; Concluding Observations Paraguay E/C.12/ PRY/CO/4 (2015); Concluding Observations UK E/C.12/GBR/CO/6 (2016), para 17; Concluding Observations Burundi E/C.12/BDI/CO/1 (2015), para 14; Concluding Observations Costa Rica E/C.12/CRI/CO/5 (2015), para 15. December 2017   The Obligation to Mobilise Resources: Bridging Human Rights, Sustainable Development Goals, and Economic and Fiscal Policies 51