What taxpayers, governments and tax economists do – and what they should do

The distinction between positive economics – describing economic programmes, situations and conditions as they exist – and normative economics – prescribing policies – has a long history. It is an especially important distinction in public economics, which by its nature concerns the actions of government. In this essay, I consider how two relatively recent developments in tax economics alter, blur or at least complicate the classic distinctions between positive and normative economics. The two developments I address are the insights generated by the study of behavioural economics and increased attention to tax evasion and tax enforcement. I organise my thoughts by addressing how three sets of actors central to public finance actually behave and should behave – taxpayers, governments and tax economists. I argue that tax economics should take seriously the substantial presence of behavioural anomalies and tax evasion, and that it has already begun to do so. I suggest some directions this effort might profitably take.