Constitutional liberalism does not require the state to provide exclusively pure public goods like defense, policing and justice or to act only as a neutral referee. All it requires is that the state strives to act exclusively in a subsidiary manner and to be minimalist in its activities, including those of wealth redistribution.
However, many who consider themselves liberals or libertarians often believe that the financing of such activities should be funded only by taxes, and preferably by a flat tax rate. Therefore, they tend to consider any progressive and inheritance taxes as unfair and inefficient redistribution of wealth that discourages the hard-working members of society.
But, in contrast to classical liberalism (or laissez faire), constitutional liberalism has no problems in relation to fair inheritance taxes and a progressive tax system. Indeed, both are even indispensable in a system based on constitutional liberalism for two simple reasons: to prevent an unfair free-riding redistribution of wealth in favor of the rich and to preserve market capitalism. We shall demonstrate the first in the case of progressive taxation and the second with reference to inheritance taxes.
The reason why in the absence of progressive taxation wealthy people would enjoy an unfair free ride is easily understood if we use a parallel with insurance cover. Even hard-line laissez-faire adepts accept that the state has a duty to protect people and property against domestic and foreign predators. So paying for that protection with taxes is similar to paying for an insurance premium based on the risks and amount of capital covered. Using a flat tax rate based on wealth would apparently achieve a fair result since everyone would pay proportionally to the amount of capital they have at risk. But this would be misleading.
Just as insurers charge premiums on the basis of both capital and risk (e.g. a one-million dollar house in a quake-prone area pays more insurance) so should the state tax differently citizens that add more risk to the community. Since greater wealth attracts more predators and consequently adds more risk, it follows that those with higher wealth should pay more than proportionally to their capital. On the contrary, since crime often breeds on poverty it also follows that it pays to reduce poverty to fight crime. So, without any social concerns in mind, on pure economic grounds we can see that to be fair taxation must be progressive.
The case for inheritance taxes is not so straightforward. These taxes work as a brake to the accumulation of wealth and since saving and accumulation are necessary to promote growth it seems that such brakes would be counterproductive. Moreover, while we can justify limiting the size of corporate wealth to prevent oligopolies and to preserve the competitive markets needed for market capitalism there are no similar argument to limit private wealth. So, the argument for inheritance taxes has to be found elsewhere.
Such argument can be found by considering the importance of credit in a capitalist system and the availability of quasi risk-free investment opportunities in debt financing. Unfortunately, after a sufficiently long period, if unchecked, debt financing together with the power of compound interest would lead to the concentration of all earthly wealth into a single family or institution. To check this out consider the case of a long lasting institution like a religious congregation and calculate the real rate of interest required for it to acquire all of today’s world wealth.
For instance, we can carry out such calculation for the priests at the Temple of Jerusalem who paid 30 pieces of silver (about USD 15,000 in today’s money) for Judas betrayal of Jesus. If instead they had invested that sum in risk-free debt, and ignoring the practical impossibility of lending at a risk-free rate after a certain level of capital accumulation, we can calculate that an interest rate of 1.28% per year would be enough for them to own now the entire world wealth estimated at almost 2000 trillion US Dollars.
However, if they were charged an inheritance tax of 20% every 50 years they would need to wait another 1000 years to own the same amount of wealth. This would not eradicate the problem of wealth concentration. But, it clearly demonstrates that inheritance taxes act as a powerful restraint on wealth concentration, without the negative consequences of the usual alternatives of war and confiscation.
For today we limit our case merely under the assumption of tax neutrality, but we shall return later to discuss if the use of taxation as a social and economic tool is compatible with a system of constitutional liberalism. Note also that, regardless of the fundamental principles that interest us, in the field of taxation the disputes over the tax pie and the practicalities of the various tax options are of vital importance. That is, we should never forget the old say that “the art of taxation consists in so plucking the goose as to obtain the largest possible amount of feathers with the smallest possible amount of hissing”.