A good summary of the Tobin Tax put forward by the TUAC Secretariat for the 123rd Plenary Session in Paris, 12 November 2009:
http://www.tuac.org/en/public/e-docs/00/00/05/D0/document_doc.phtml
I find interesting the section that describes why the IMF was opposed to a Tobin Tax before:-
The views of the IMF and OECD
8. Both the IMF and the OECD have been consistently sceptical on the desirability and practicality of a Tobin Tax. Several IMF papers, such as a 1996 article by the Fiscal Affairs
Department, have argued why such global tax âwonât workâ. The OECD has not departed from this view and in June 2002 published a stand alone chapter in its Economic Outlook publication summing up the arguments by the IMF and the OECD against at the Tobin tax.
- Frequent or short term trading is not a bad thing, it contributes to risk management and compensate for market opacity. Frequent traders and higher levels of daily trading can reduce volatility by increasing distribution of risks, and for markets that lacks transparency on pricing as is the case of foreign exchange markets it contributes to the âprice discoveryâ process (i.e. one needs to buy or sale to actually know the market price), and hence facilitate risk management by investors.
- A Tobin Tax would increase market volatility (by reducing frequent trading). Thereis no evidence that a Tobin tax would reduce currency exchange volatility. In fact such tax would increase it. Any reduction in trade volume would not discriminate between good trades (i.e. arbitrage that has stabilising effects by reducing interest rate spreads) and bad trades. Less trading volume concentrates risks and hampers investorsâ management of risk
and hence increases the cost of capital. For shallow markets in particular (those with few daily transactions) the tax would create liquidity problems and would increase volatility dramatically; because there would be less frequent traders, the markets could be subject to
abrupt price movements due to a single transaction.
- Volatility does not impact trade. The beneficial effect of reducing cost of insurance against volatility of a Tobin tax on trade and investment has not been proven. Theoretically there is no consensus on the impact of higher volatility on trade, and empirically the negative impact appears not to be large.
- The Tax would dry up the derivatives market. To be effective, the tax would need to apply to derivative products that precisely aim at ensuring investors against volatility risks. In doing so the tax risks drying up the derivative market or at minimum would higher the cost of insuring possibly by more than they would be lowered by any reduction
in volatility.
- It would weaken market discipline on governments. Because the tax would reduce the ability of markets to respond instantly to policy changes or announcements, it would reduce market discipline on policy makers and governments.
- Implementation could well prove insurmountable. If not, trading would tend to migrate to other, non-taxed jurisdictions, which may well be less regulated than existing venues, or participants could use other financial vehicles to achieve the same end.
- Allocating Tax revenues would become a problem on its own. If it were possible to implement the Tax, the revenue yield from such a tax could be significant but would rapidly decrease in good part because the tax base itself is likely to fall. Even so, earmarking the revenues from such a tax for specific, albeit highly legitimate, expenditures, like ODA, would seem to be âneither economically efficient, nor politically
optimalâ.
- Political feasibility. The political conditions to implement and enforce such tax are not currently in place.