FOR almost as long as big business has been crusading for a lower rate of company tax, I've been puzzling over its motives. Why are these people fighting for something of little or no benefit to their domestic shareholders and likely to be quite unpopular?
The willingness with which our economic establishment has gone along with the calls for lower company taxes is one of the great mysteries of 2012. Now the Organisation for Economic Co-operation and Development has signed up as an urger in its latest report on Australia.
But as David Richardson demonstrated on Saturday in his technical brief for the Australia Institute, claims that a lower rate of company tax would lead to more investment, faster economic growth and higher employment are surprisingly weak when you bother to examine them.
The puzzle doesn't end there, however. If lower company tax was of benefit to shareholders, it wouldn't be surprising to see big business arguing for it, even if it was of little or no benefit to the wider economy. But even this motivation doesn't hold.
The push for lower company tax is enthusiastically pursued in the United States, and this wouldn't be the first reform push we'd imported holus-bolus from there. Just one small problem: we have a full dividend imputation system that America doesn't.
It wouldn't be all that surprising if many economists - and many punters - weren't quite on top of how dividend imputation affects the push for a lower company tax rate.
It would be amazing, however, if our chief executives didn't understand it. You'd also expect a lot of investment professionals to know the score.
The point is simply stated: when the rate of company tax is 30 per cent, the recipients of 'fully franked' dividends are entitled to a refundable tax credit worth 30 per cent of the 'grossed-up' value of the dividend.
So if your marginal tax rate is 46.5 per cent, the extra income tax you have to pay on your grossed-up dividend falls to a net 16.5 per cent. In this way the double taxation of dividends is eliminated.
Now let's say the big business lobby succeeds in persuading the government to cut the company tax rate to 25 per cent. With an unchanged dividend, the refundable tax credit falls to 25 per cent and the remaining tax to be paid rises to 21.5 per cent.
Only if companies were to respond to the lower company tax rate by increasing their dividend payouts sufficiently would domestic shareholders not see themselves as having been made worse off.
The introduction of dividend imputation led to a reduction in listed companies' efforts to minimise their company tax because Australian investors much prefer to hold the shares of companies paying enough tax to allow them to fully frank their dividends. Companies unable to deliver fully franked dividends can expect their share price to be marked down accordingly.
This is particularly true of Australian super funds, which are able to use imputation credits to largely extinguish the 15 per cent tax they pay on their annual investment earnings. (This tax quirk probably explains why our super funds are overinvested in shares and underinvested in fixed-interest.)
When you remember the way our chief executives bang on endlessly about shareholder value being their sole and sacred objective, you can only wonder why they pursue a cut in the company tax rate so fervently.
They're always distributing league tables showing our 30 per cent company tax rate as the equal-seventh highest among the 34 countries in the OECD. They never point to tables showing the combined effect of the company tax rate and the top personal tax rate. If they looked at it from this, domestic shareholders' perspective we'd fall to being just the 15th highest, with the US and Britain well above us.
For a long time I wondered whether the Business Council - many of whose members are largely foreign-owned - was championing the interests of foreign shareholders rather than locals.
It's true many foreign shareholders in Australian companies would benefit from a lower company tax rate because they're not eligible for imputation credits. One of the main reasons for the continued existence of company tax is to ensure the foreign owners of Australian businesses pay their fair share of Australian tax.
But not even all foreign shareholders would benefit from lower company tax. Americans (who account for more than a quarter of the stock of foreign investment in Australia) would gain nothing because the company tax rate they pay when they bring dividends home is already higher than our 30 per cent (for which they get a deduction). They wouldn't gain, but our Treasury would lose.
So what is big business on about? In his paper, Richardson argues it's a case of company executives pursuing their own interests, not those of the shareholders they profess to serve. (Economists call this a principal-and-agent problem.)
A lower rate of company tax would make companies' after-tax profits bigger, thus making their chief executives look more successful and probably leading to an increase in their remuneration.
It would also allow companies to retain and reinvest more after-tax earnings. This would make their companies bigger - which would probably also justify bosses being paid higher remuneration.
We already know chief executives play such self-seeking games because of all the mergers and takeovers, which rarely leave shareholders better off, but invariably leave the instigating chief executive more highly paid.