A report co-authored by a UN judge has added to growing international calls for reparations to be paid by perpetrators of transatlantic slavery. The Brattle Group Report calculates 31 former slaveholding states including Britain, the US, France and Spain owe US$107.8 trillion, with the UK alone owing more than £18 trillion for its involvement in slavery in fourteen countries. Professor Trevor Burnard is Director of the Wilberforce Institute for the Study of Slavery and Emancipation at the University of Hull in the UK. He has written of the need for the British royal family to acknowledge its financial and moral responsibility for Britain's role in slavery.