On Monday this week representatives of Starbucks, Amazon and Google faced MPs to have their companies' tax affairs scrutinised in a quite ferocious manner. Select committees have become a kind of reality show where MPs get to look look tough and funny and deliver a few zingers at wrongdoers - and the more public the wrong doing, the more aggressive the questioning. (see G4S and Murdoch). Sometimes this is all a bit daft but MPs' indignation seemed to genuinely reflect what ordinary UK taxpayers are increasingly thinking. "Your entire business is here but you pay no tax here and that really riles us", Margaret Hodge told Amazon's Andrew Cecil. If this response to Starbucks' staement on its tax affairs is any guide then she's right, all of a sudden it does seem to rile us.
Interestingly, it seems that the real public breakthrough moment may end up being the response of the those firms when questioned by the Public Accounts Committee. If there's one thing we don't like, it's being treated like idiots. Tuesday's Daily Mail was scathing in its analysis of how these firms have acted. It's been huge news in an already huge news week.
As an issue, corporate tax avoidance has been bubbling for ages. The Tax Justice Network has been doing mind-bogglingly wonky (and brilliant) work on corporate tax for years. Organisations like ActionAid and Christian Aid have been looking into how big business' tax affairs impact on developing countries. UK Uncut's creative tactics against high street tax avoiders have been making headlines since 2010.
Campaigners who've been plugging away at this issue should be proud. It's hard work to make an issue like this capture the public imagination - but when it does and it sticks it can be unstoppable. The broad and loose alliance of faith groups, charities, activists and even the Daily Mail have served to bring this important issue out of the finance think tanks and into people's consciousness. On Monday this came to a head in front of a committee of riled MPs who did a grand job of holding this firms to account, but without members of the public taking action and getting involved, it never would have got there at all.
In the end, what really matters is how policy makers respond to this challenge and it's yet to be seen whether they'll take decisive action on tax avoidance. From a campaigning perspective, however, seeing these firms put through their paces on Monday was certainly a victory of sorts and the journey from accountancy wonkery to fully fledged public outrage has been fascinating.
It's easy for politicians to look tough by asking questions, it's harder for them to stand up and take action. The challenge for campaigners now is how to turn this surge of interest in tax avoidance into people-powered pressure that forces a genuine, tangible result.
Follow John Coventry on Twitter: www.twitter.com/johnnycov