A US court has just ruled that we must not hold credit card companies responsible for the piratical exploits of copyright-flouting scallywags.

As our transatlantic cousins would have it themselves: dude, duh!

The world of law is full of flawed logic and claims that stretch the imagination, the world of technology law being no exception.

When nudie picture firm Perfect 10 sought to hold Visa and Mastercard responsible for people stealing their photos it was a bad day for logic.

It got worse when one of the judges in Perfect 10's appeal against an initial rejection of its argument actually said he thought credit card firms should be responsible. The court, in California, sent Perfect 10 packing, but not before judge Alex Kozinski dissented with the majority verdict. "If cards don't process payment, pirates don't deliver booty."

"The credit cards, in fact, control distribution of the infringing material," he said. "It does not serve the interests of a free market, or a free society, to abet marauders who pilfer the property of law-abiding, tax-paying rights holders, and who turn consumers into recipients of stolen property."

Credit cards create a financial bridge between infringer and buyer, he said. The cider tap creates a financial bridge between students and penury, should they sue Strongbow because they only have enough cash for coleslaw and sausages at the end of term?

This drive to deal with a problem by suing everyone involved at any stage of a process when something bad happens is utterly lamentable.

That is not to say that credit card firms have no role in the prevention of crimes. When the US banned online gambling they did so by making it illegal for financial services firms, including credit card companies, to process online gambling transactions for US residents.

As an instrument for public policy they can be useful. But that doesn't mean that every time somebody charges for something they shouldn't, the credit card companies take a hit.