The domicile rules create two systems of personal taxation system in the UK. One charges over 99% of UK residents to tax on their world wide income and gains. The other charges well under 1% to tax on their UK source income and gains. This will remain true after the proposed changes due to come into effect after 6 April this year.

The question to be asked is a simple one: can anyone justify on any logical, ethical or practical basis having two systems of tax in one country when the factor that most obviously differentiates who has access to the favoured system is wealth?

This practice contravenes all principles of the Enlightenment on which the democratic state is built: that all people are not equal before the law.

And the domicile rule contravenes all principles of taxation as laid down by Adam Smith and just about anyone else thereafter (me included). It's not equitable, simple, certain or efficient for a start, despite which tax practitioners apparently love it (giving lie to their supposed liking for simplicity on the way) . Nor does it accord with the principle of progressive taxation.

Finally, the domicile rule is not pragmatic. Two systems increase confusion, and so reduce compliance. Two systems, with the wealthy being favoured, reduces acceptance of the tax system within society and will reduce all others willingness to pay. As Alex Brumner says in the Mail :

The doctors and traders who work alongside [non-domiciled colleagues] and within the traditional PAYE system, may wonder why overseas colleagues should enjoy this privilege in the first place.

Why has this point been ignored? Getting rid of this disparity will raise more than the loss from any non-doms leaving.

There is no justification for the domicile rule in taxation.