As the readers of this blog would know, I have been advocating more symmetric tax treatment of equity and debt, both in terms of public and private bonds and lending taxation. Here's a recent IMF paper on the topic that provides evidence that asymmetric taxation of debt and equity, with preferential treatment of debt over equity, generated internal instability in the system, making it more prone to crises.
Mooij, Ruud A., Keen, Michael and Orihara, Masanori paper "Taxation, Bank Leverage, and Financial Crises" (February 2013). IMF Working Paper No. 13/48 argues that "that most corporate tax systems favor debt over equity finance is now widely recognized as, potentially, amplifying risks to financial stability. This paper makes a first attempt to explore, empirically, the link between this tax bias and the probability of financial crisis."
The study "…finds that greater tax bias is associated with significantly higher aggregate bank leverage, and that this in turn is associated with a significantly greater chance of crisis. The implication is that tax bias makes crises much more likely, and, conversely, that the welfare gains from policies to alleviate it can be substantial far greater than previous studies, which have ignored financial stability considerations, suggest."
The paper "aims to provide a first attempt to establish and quantify an empirical link between the tax incentives that encourage financial institutions (more precisely, banks, the group for which we have data) to finance themselves by debt rather than equity and the likelihood of financial crises erupting; and then to try to quantify the welfare gains that policies to address this bias might consequently yield."
The paper combines two elements in a causal chain:
"The first is that between the statutory corporate tax rate and banks’ leverage. This has received substantial attention in relation to non-financial firms, but very little in relation to the financial sector. Keen and De Mooij (2011), however, show that for banks too a higher corporate tax rate, amplifying the tax advantage of debt over equity finance, should in principle lead to higher levels of leverage; the presence of capital regulations does not affect the usual tax bias applying, so long as it is privately optimal for banks to hold some buffer over regulatory requirements (as they generally do).
[In other words, capital requirements regulations are not sufficient to address the problem created by skewed incentives. The authors state that "Regulation, of course, has historically had the dominant role in addressing such problems of excess leverage in the financial sector, and the higher and tighter capital requirements of Basel III should to some degree reduce the welfare costs of debt bias."]
Empirically too, Keen and de Mooij (2012) find that, for a large cross-country panel of banks, tax effects on leverage are significant—and, on average, about as large as for non-financial institutions. These effects are very much smaller, they also find, for the largest banks, which generally account for the vast bulk of all bank assets. …Importantly, the finding that tax distortions to leverage are small for the larger banks, which are massively larger than the rest, does not mean that the welfare impact of tax distortions is in aggregate negligible: even small changes in the leverage of very large banks could have a large impact on the likelihood of their distress or failure, and hence on the likelihood of financial crisis."
The second link in the causal chain is the link "between the aggregate leverage of the financial sector and the probability of financial crisis. We estimate such a relationship for OECD countries, …capturing data on the recent financial crisis… The results suggest sizeable and highly nonlinear effects of aggregate bank leverage on the probability of financial crisis."
"… we consider three tax reforms that would reduce the tax incentive to debt finance:
- a cut in the corporate tax rate;
- adoption of an Allowance for Corporate Equity form of corporate tax (which would in principle eliminate debt bias); and
- a ‘bank levy’ of broadly the kind that a dozen or so countries have introduced since the crisis."
"The implications of these reforms for aggregate leverage are readily estimated using the results above.
- We suppose, as before, that a 1 percentage point reduction in the CIT rate reduces banks’ aggregate leverage by somewhere between 0.04 and 0.15.
- This means, for instance, that the bank levy of 10 bp would reduce financial leverage by between 0.1 and 0.4 percentage points, for example from 93 percent to 92.9 or 92.6.
- Eliminating debt bias altogether with an ACE would reduce leverage by 2.2 percentage points under what we shall take to be the central estimate of 0.08: say, from 93 to 90.8; with the upper bound estimate of 0.15, leverage would fall by 4.2 percentage points."
The above clearly suggests that ACE approach, basically removing disincentive to equity funding compared to other policy alternatives. It also shows that in impact terms, lower corporate tax rates are not sufficient to eliminate or reduce the adverse effects of the asymmetric treatment of debt against equity.