If Hartford, or anybody else, is able to come up some better way of processing GST at the border, without imposing undue hassle on either those who might be deterred from exporting to New Zealand or on Kiwi shoppers, and without collection costs that exceed the value of the GST collected, that would be great.
I’ll quibble a bit at the wording, the collection costs should not exceed the value of the improved allocative efficiency from removing a tax distortion, not the revenue collected, which is likely a much tougher hurdle, but either way I’m prepared to give it a go.
My proposal will not just deal with the distortion that purchases by consumers that are made directly from overseas through on-line retailing receive a favourable tax treatment relative to those that are processed through an importer. It will also deal with a larger distortion in the GST. As it currently stands, the GST applied to imports does not apply to purchases made by New Zealanders while travelling overseas, and similarly the zero-rating of exports does not apply to the sale of services to foreign tourists while in New Zealand. That is, the current GST regime favours overseas tourism by New Zealanders over other imports, and penalises the New Zealand tourism industry relative to other exports.
So here is my proposal: Completely exempt all imports from the GST, and at the same time stop zero-rating exports and require firms to charge GST on all sales, including those to foreigners. Retail New Zealand should be happy, they would no longer be treated in differently from overseas on-line sellers in their tax treatment in New Zealand. And firms selling both overseas and in New Zealand would be happy to no longer have to have separate out sales overseas and domestic sales when filing their tax returns.
This idea runs completely counter to our inner mercantilist instincts, but our instincts don’t cope well with general-equilibrium reasoning. In my experience the greatest eye-opening moment you can give students in economics—the sort of epiphany that has them changing instantly from “this is obviously wrong” to “this is obviously right” is the Lerner symmetry theorem, which shows that an import tax is exactly equivalent to an export tax. The idea here is that a tax on exports or imports is really a tax on trade. In the long-run, the present value of exports has to equal the present value of imports, as they are just opposite sides of the equals sign in a budget constraint. A tax on exports is a tax on imports, as it shifts resources away from producing for overseas (with the consequent importing from overseas that that allows) to producing for local consumption. (I was told that, during the Muldoon era, Treasury, knowing that it could not pursuade Muldoon to reduce tarrifs encouraged him in his policy of export subsidies, knowing that the latter would counteract the former.)
In a country with a floating exchange rate, the way that the Lerner equivalence theorem would play out if it were to adopt the change from levying the GST on imports to levying it on exports, would be through a depreciation of the currency by the amount of the GST. So sure exporters would have to put up their prices to foreigners in NZ dollars by 15%, but the goods would not seem to be more expensive to foreigners because of the 15% depreciation. Similarly, the 15% GST coming off imports would be offset by the depreciation. In general, therefore, there would be no change, but with a few exceptions. On-line purchases would become 15% more expensive in NZ dollars due to the depreciation with no offsetting change in taxes. Trips overseas would similarly become 15% more expensive, but at the same time, New Zealand would become a far cheaper place for foreigners to visit, again.
I don’t imagine for a moment that any government would implement this policy. Instinctive mercantilism is too strong in all voters, and only a few have experienced the epiphany of general equilibrium reasoning. But this is not a “modest proposal” in the Swiftian sense. I am deadly serious.