OPINION:The argument to ban the financial instrument used to destabilise EU states is compelling, writes WOLFGANG MÜNCHAU

I GENERALLY do not like to propose bans. But I cannot understand why we are still allowing the trade in credit default swaps without ownership of the underlying securities.

Especially in the euro zone, which is subject to a series of speculative attacks, a generalised ban on “naked CDSs” should be a no-brainer.

Naked CDSs are the instrument of choice for those who take large bets against European governments, most recently in Greece.

Ben Bernanke, the chairman of the Federal Reserve, said last week that the Fed was investigating “a number of questions relating to Goldman Sachs and other companies in their derivatives arrangements with Greece”. Using CDSs to destabilise a government was “counter-productive”, he said. Unfortunately, it is legal.

CDSs are over-the-counter contracts negotiated by two parties. They offer the buyer insurance on a bundle of underlying securities.

A typical bundle would be €10 million worth of Greek government bonds. To insure against default, the buyer of a CDS pays the seller a premium, whose value is denoted in basis points. Last Thursday, a CDS contract on five-year Greek bonds was quoted at 394 basis points.

This means that it costs the buyer €394,000 per year, for five years, to insure against default. If Greece defaults, the buyer gets €10 million, or some equivalent. What constitutes default is subject to a complicated legal definition.

A naked CDS purchase means that you take out insurance on bonds without actually owning them. It is a purely speculative gamble. There is not one social or economic benefit. Even hardened speculators agree on this point.

Especially because naked CDSs constitute a large part of all CDS transactions, the case for banning them is about as strong as that for banning bank robberies.

Economically, CDSs are insurance for the simple reason that they insure the buyer against the default of an underlying security. A universally accepted aspect of insurance regulation is that you can only insure what you actually own. Insurance is not meant as a gamble, but an instrument to allow the buyer to reduce incalculable risks. Not even the most libertarian extremist would accept that you could take out insurance on your neighbour’s house or the life of your boss.

Technically, CDSs are not classified as insurance but as swaps because they involve an exchange of cash flows. The CDS lobby makes much of those technical characteristics in its defence of the status quo. But this is misleading. Even a traditional insurance contract can be viewed as a swap, as it involves an exchange of cash flows. But nobody in their right mind would use the swap-like characteristics of an insurance contract as an excuse not to regulate the insurance industry. The fact that, unlike insurance, CDSs are tradeable contracts, does not change the fundamental economic rationale.

The whole idea of modern financial products is to replicate the payment streams of other, more traditional instruments, while offering better conditions.

Selling a CDS is like buying a bond. Buying a CDS is a way of shorting a bond – or of insuring against its default. But that does not change the fact that once you strip away the complex technical machinery, you end up with a product that offers insurance, even though it is a lot more versatile than a standard insurance contract.

Another argument I have heard from a lobbyist is that naked CDSs allow investors to hedge more effectively. This is like saying that a bank robbery brings benefits to the robber. A further stated objection to a ban is that it would be difficult to police. There is no question that a ban of a complex product, such as a CDS, involves technical complexities that commentators like myself probably underestimate. It is conceivable, for example, that the industry might quickly find a legal way round such a ban.

Then again, we would not consider legalising bank robberies on the grounds that it is difficult to catch the robber.

So why are we so cautious? From conversations with regulators and law-makers, I suspect they are not always familiar with those products, to put it kindly, and that they may be afraid of regulating something they do not understand. They understand, or think they do, what a hedge fund is. Restricting hedge funds is something they can sell to their electorates. Hedge funds were not at the centre of the crisis, but they are a politically expedient target. Banning products with ugly acronyms that nobody understands seems like unnecessarily hard work.

I do not want to exaggerate the case for a ban. This speculation is neither the underlying cause of the global financial crisis, nor of the euro zone’s underlying economic tensions. But naked CDSs have played an important and direct role in destabilising the financial system. They still do.

And banks, whose shareholders and employees have benefited from public rescue programmes, are now using CDSs to speculate against governments.

Where is the political response? The Germans want to bring it to the G-20, but they hesitate to do anything unilaterally. Christine Lagarde, the French finance minister, was recently quoted as saying: “What we are going to take away from this crisis is certainly a second look at the validity, solidity of sovereign .”

A second look? I wonder what they saw when they looked the first time. – (Copyright The Financial Times Limited 2010)