It is a commonplace that if a tax system is to command a high level of acceptance and compliance, it must be generally perceived to be a fair system, fairly administered.

So, whatever the truth of the matter, the perception of Joe Public that the likes of Amazon, Starbucks, Google and Vodafone are bearing less than their fair share of the UK tax burden has a potential impact which is much more important than the mere financial one of the contribution of even the odd hundred million pounds more or less to the Exchequer.