As I've already noted this morning, Barclays has decided to review its sales of tax products as “some of them may no longer be appropriate”.

There are lessons to be learned from this. The first is that, as Barclays has now learned to its cost, tax avoidance does not pay.

The second is that companies are not required to minimise their tax bills: no one will be threatening Barclays with litigation for changing its policy. It is entirely legitimate for it to do so.

In that case let's be clear what Barclays has now proved once and for all: paying tax is a matter of corporate choice. It chose to act inappropriately. Now it says it is going to choose to act appropriately (whether I'd always agree is another issue). And what's critical is that this reveals that tax decisions are a mater of ethical choice between what is appropriate and not.

The Tax Justice Network and I have said this for years. It's always and very obviously been true. But confirmation from Barclays was unexpected and welcome.

Now can we lay the fatuous argument that there is no morality in tax to rest for good simply because it's very obviously wrong, and as Barclays have proved, it's only used by those who know they are wrong.